mtype.c

// Compiler implementation of the D programming language
// Copyright (c) 1999-2012 by Digital Mars
// All Rights Reserved
// written by Walter Bright
// http://www.digitalmars.com
// License for redistribution is by either the Artistic License
// in artistic.txt, or the GNU General Public License in gnu.txt.
// See the included readme.txt for details.

#define __C99FEATURES__ 1       // Needed on Solaris for NaN and more
#define __USE_ISOC99 1          // so signbit() gets defined

#include <math.h>
#include <stdio.h>
#include <assert.h>
#include <float.h>

#if _MSC_VER
#include <malloc.h>
#include <complex>
#include <limits>
#elif __DMC__
#include <complex.h>
#elif __MINGW32__
#include <malloc.h>
#endif

#include "rmem.h"
#include "port.h"
#include "target.h"

#include "dsymbol.h"
#include "mtype.h"
#include "scope.h"
#include "init.h"
#include "expression.h"
#include "statement.h"
#include "attrib.h"
#include "declaration.h"
#include "template.h"
#include "id.h"
#include "enum.h"
#include "module.h"
#include "import.h"
#include "aggregate.h"
#include "hdrgen.h"

FuncDeclaration *hasThis(Scope *sc);

#define LOGDOTEXP       0       // log ::dotExp()
#define LOGDEFAULTINIT  0       // log ::defaultInit()

// Allow implicit conversion of T[] to T*  --> Removed in 2.063
#define IMPLICIT_ARRAY_TO_PTR   0

int Tsize_t = Tuns32;
int Tptrdiff_t = Tint32;

/***************************** Type *****************************/

ClassDeclaration *Type::typeinfo;
ClassDeclaration *Type::typeinfoclass;
ClassDeclaration *Type::typeinfointerface;
ClassDeclaration *Type::typeinfostruct;
ClassDeclaration *Type::typeinfotypedef;
ClassDeclaration *Type::typeinfopointer;
ClassDeclaration *Type::typeinfoarray;
ClassDeclaration *Type::typeinfostaticarray;
ClassDeclaration *Type::typeinfoassociativearray;
ClassDeclaration *Type::typeinfovector;
ClassDeclaration *Type::typeinfoenum;
ClassDeclaration *Type::typeinfofunction;
ClassDeclaration *Type::typeinfodelegate;
ClassDeclaration *Type::typeinfotypelist;
ClassDeclaration *Type::typeinfoconst;
ClassDeclaration *Type::typeinfoinvariant;
ClassDeclaration *Type::typeinfoshared;
ClassDeclaration *Type::typeinfowild;

TemplateDeclaration *Type::associativearray;
TemplateDeclaration *Type::rtinfo;

Type *Type::tvoid;
Type *Type::tint8;
Type *Type::tuns8;
Type *Type::tint16;
Type *Type::tuns16;
Type *Type::tint32;
Type *Type::tuns32;
Type *Type::tint64;
Type *Type::tuns64;
Type *Type::tint128;
Type *Type::tuns128;
Type *Type::tfloat32;
Type *Type::tfloat64;
Type *Type::tfloat80;

Type *Type::timaginary32;
Type *Type::timaginary64;
Type *Type::timaginary80;

Type *Type::tcomplex32;
Type *Type::tcomplex64;
Type *Type::tcomplex80;

Type *Type::tbool;
Type *Type::tchar;
Type *Type::twchar;
Type *Type::tdchar;

Type *Type::tshiftcnt;
Type *Type::tboolean;
Type *Type::terror;
Type *Type::tnull;

Type *Type::tsize_t;
Type *Type::tptrdiff_t;
Type *Type::thash_t;
Type *Type::tindex;

Type *Type::tvoidptr;
Type *Type::tstring;
Type *Type::tvalist;
Type *Type::basic[TMAX];
unsigned char Type::mangleChar[TMAX];
unsigned char Type::sizeTy[TMAX];
StringTable Type::stringtable;


Type::Type(TY ty)
{
    this->ty = ty;
    this->mod = 0;
    this->deco = NULL;
#if DMDV2
    this->cto = NULL;
    this->ito = NULL;
    this->sto = NULL;
    this->scto = NULL;
    this->wto = NULL;
    this->swto = NULL;
#endif
    this->pto = NULL;
    this->rto = NULL;
    this->arrayof = NULL;
    this->vtinfo = NULL;
    this->ctype = NULL;
}

const char *Type::kind()
{
    assert(false); // should be overridden
    return NULL;
}

Type *Type::syntaxCopy()
{
    print();
    fprintf(stderr, "ty = %d\n", ty);
    assert(0);
    return this;
}

bool Type::equals(RootObject *o)
{
    Type *t = (Type *)o;
    //printf("Type::equals(%s, %s)\n", toChars(), t->toChars());
    if (this == o ||
        ((t && deco == t->deco) &&               // deco strings are unique
          deco != NULL))                         // and semantic() has been run
    {
        //printf("deco = '%s', t->deco = '%s'\n", deco, t->deco);
        return true;
    }
    //if (deco && t && t->deco) printf("deco = '%s', t->deco = '%s'\n", deco, t->deco);
    return false;
}

char Type::needThisPrefix()
{
    return 'M';         // name mangling prefix for functions needing 'this'
}

void Type::init()
{
    stringtable._init(1543);
    Lexer::initKeywords();

    for (size_t i = 0; i < TMAX; i++)
        sizeTy[i] = sizeof(TypeBasic);
    sizeTy[Tsarray] = sizeof(TypeSArray);
    sizeTy[Tarray] = sizeof(TypeDArray);
    sizeTy[Taarray] = sizeof(TypeAArray);
    sizeTy[Tpointer] = sizeof(TypePointer);
    sizeTy[Treference] = sizeof(TypeReference);
    sizeTy[Tfunction] = sizeof(TypeFunction);
    sizeTy[Tdelegate] = sizeof(TypeDelegate);
    sizeTy[Tident] = sizeof(TypeIdentifier);
    sizeTy[Tinstance] = sizeof(TypeInstance);
    sizeTy[Ttypeof] = sizeof(TypeTypeof);
    sizeTy[Tenum] = sizeof(TypeEnum);
    sizeTy[Ttypedef] = sizeof(TypeTypedef);
    sizeTy[Tstruct] = sizeof(TypeStruct);
    sizeTy[Tclass] = sizeof(TypeClass);
    sizeTy[Ttuple] = sizeof(TypeTuple);
    sizeTy[Tslice] = sizeof(TypeSlice);
    sizeTy[Treturn] = sizeof(TypeReturn);
    sizeTy[Terror] = sizeof(TypeError);
    sizeTy[Tnull] = sizeof(TypeNull);

    mangleChar[Tarray] = 'A';
    mangleChar[Tsarray] = 'G';
    mangleChar[Taarray] = 'H';
    mangleChar[Tpointer] = 'P';
    mangleChar[Treference] = 'R';
    mangleChar[Tfunction] = 'F';
    mangleChar[Tident] = 'I';
    mangleChar[Tclass] = 'C';
    mangleChar[Tstruct] = 'S';
    mangleChar[Tenum] = 'E';
    mangleChar[Ttypedef] = 'T';
    mangleChar[Tdelegate] = 'D';

    mangleChar[Tnone] = 'n';
    mangleChar[Tvoid] = 'v';
    mangleChar[Tint8] = 'g';
    mangleChar[Tuns8] = 'h';
    mangleChar[Tint16] = 's';
    mangleChar[Tuns16] = 't';
    mangleChar[Tint32] = 'i';
    mangleChar[Tuns32] = 'k';
    mangleChar[Tint64] = 'l';
    mangleChar[Tuns64] = 'm';
    mangleChar[Tfloat32] = 'f';
    mangleChar[Tfloat64] = 'd';
    mangleChar[Tfloat80] = 'e';

    mangleChar[Timaginary32] = 'o';
    mangleChar[Timaginary64] = 'p';
    mangleChar[Timaginary80] = 'j';
    mangleChar[Tcomplex32] = 'q';
    mangleChar[Tcomplex64] = 'r';
    mangleChar[Tcomplex80] = 'c';

    mangleChar[Tbool] = 'b';
    mangleChar[Tascii] = 'a';
    mangleChar[Twchar] = 'u';
    mangleChar[Tdchar] = 'w';

    // '@' shouldn't appear anywhere in the deco'd names
    mangleChar[Tinstance] = '@';
    mangleChar[Terror] = '@';
    mangleChar[Ttypeof] = '@';
    mangleChar[Ttuple] = 'B';
    mangleChar[Tslice] = '@';
    mangleChar[Treturn] = '@';
    mangleChar[Tvector] = '@';
    mangleChar[Tint128] = '@';
    mangleChar[Tuns128] = '@';

    mangleChar[Tnull] = 'n';    // same as TypeNone

    for (size_t i = 0; i < TMAX; i++)
    {   if (!mangleChar[i])
            fprintf(stderr, "ty = %llu\n", (ulonglong)i);
        assert(mangleChar[i]);
    }

    // Set basic types
    static TY basetab[] =
        { Tvoid, Tint8, Tuns8, Tint16, Tuns16, Tint32, Tuns32, Tint64, Tuns64,
          Tint128, Tuns128,
          Tfloat32, Tfloat64, Tfloat80,
          Timaginary32, Timaginary64, Timaginary80,
          Tcomplex32, Tcomplex64, Tcomplex80,
          Tbool,
          Tascii, Twchar, Tdchar };

    for (size_t i = 0; i < sizeof(basetab) / sizeof(basetab[0]); i++)
    {   Type *t = new TypeBasic(basetab[i]);
        t = t->merge();
        basic[basetab[i]] = t;
    }
    basic[Terror] = new TypeError();

    tvoid = basic[Tvoid];
    tint8 = basic[Tint8];
    tuns8 = basic[Tuns8];
    tint16 = basic[Tint16];
    tuns16 = basic[Tuns16];
    tint32 = basic[Tint32];
    tuns32 = basic[Tuns32];
    tint64 = basic[Tint64];
    tuns64 = basic[Tuns64];
    tint128 = basic[Tint128];
    tuns128 = basic[Tuns128];
    tfloat32 = basic[Tfloat32];
    tfloat64 = basic[Tfloat64];
    tfloat80 = basic[Tfloat80];

    timaginary32 = basic[Timaginary32];
    timaginary64 = basic[Timaginary64];
    timaginary80 = basic[Timaginary80];

    tcomplex32 = basic[Tcomplex32];
    tcomplex64 = basic[Tcomplex64];
    tcomplex80 = basic[Tcomplex80];

    tbool = basic[Tbool];
    tchar = basic[Tchar];
    twchar = basic[Twchar];
    tdchar = basic[Tdchar];

    tshiftcnt = tint32;
    tboolean = tbool;
    terror = basic[Terror];
    tnull = basic[Tnull];
    tnull = new TypeNull();
    tnull->deco = tnull->merge()->deco;

    tvoidptr = tvoid->pointerTo();
    tstring = tchar->immutableOf()->arrayOf();
    tvalist = tvoid->pointerTo();

    if (global.params.isLP64)
    {
        Tsize_t = Tuns64;
        Tptrdiff_t = Tint64;
    }
    else
    {
        Tsize_t = Tuns32;
        Tptrdiff_t = Tint32;
    }

    tsize_t = basic[Tsize_t];
    tptrdiff_t = basic[Tptrdiff_t];
    thash_t = tsize_t;
    tindex = tsize_t;
}

d_uns64 Type::size()
{
    return size(Loc());
}

d_uns64 Type::size(Loc loc)
{
    error(loc, "no size for type %s", toChars());
    return SIZE_INVALID;
}

unsigned Type::alignsize()
{
    return size(Loc());
}

Type *Type::semantic(Loc loc, Scope *sc)
{
    if (ty == Tint128 || ty == Tuns128)
    {
        error(loc, "cent and ucent types not implemented");
        return terror;
    }

    return merge();
}

Type *Type::trySemantic(Loc loc, Scope *sc)
{
    //printf("+trySemantic(%s) %d\n", toChars(), global.errors);
    unsigned errors = global.startGagging();
    Type *t = semantic(loc, sc);
    if (global.endGagging(errors))        // if any errors happened
    {
        t = NULL;
    }
    //printf("-trySemantic(%s) %d\n", toChars(), global.errors);
    return t;
}

/********************************
 * Return a copy of this type with all attributes null-initialized.
 * Useful for creating a type with different modifiers.
 */

Type *Type::nullAttributes()
{
    unsigned sz = sizeTy[ty];
    Type *t = (Type *)mem.malloc(sz);
    memcpy(t, this, sz);
    // t->mod = NULL;  // leave mod unchanged
    t->deco = NULL;
    t->arrayof = NULL;
    t->pto = NULL;
    t->rto = NULL;
    t->cto = NULL;
    t->ito = NULL;
    t->sto = NULL;
    t->scto = NULL;
    t->wto = NULL;
    t->swto = NULL;
    t->vtinfo = NULL;
    t->ctype = NULL;
    if (t->ty == Tstruct) ((TypeStruct *)t)->att = RECfwdref;
    if (t->ty == Tclass) ((TypeClass *)t)->att = RECfwdref;
    return t;
}

/********************************
 * Convert to 'const'.
 */

Type *Type::constOf()
{
    //printf("Type::constOf() %p %s\n", this, toChars());
    if (mod == MODconst)
        return this;
    if (cto)
    {   assert(cto->mod == MODconst);
        return cto;
    }
    Type *t = makeConst();
    t = t->merge();
    t->fixTo(this);
    //printf("-Type::constOf() %p %s\n", t, t->toChars());
    return t;
}

/********************************
 * Convert to 'immutable'.
 */

Type *Type::immutableOf()
{
    //printf("Type::immutableOf() %p %s\n", this, toChars());
    if (isImmutable())
    {
        return this;
    }
    if (ito)
    {
        assert(ito->isImmutable());
        return ito;
    }
    Type *t = makeInvariant();
    t = t->merge();
    t->fixTo(this);
    //printf("\t%p\n", t);
    return t;
}

/********************************
 * Make type mutable.
 */

Type *Type::mutableOf()
{
    //printf("Type::mutableOf() %p, %s\n", this, toChars());
    Type *t = this;
    if (isConst())
    {   if (isShared())
            t = sto;            // shared const => shared
        else
            t = cto;            // const => naked
        assert(!t || t->isMutable());
    }
    else if (isImmutable())
    {   t = ito;                // immutable => naked
        assert(!t || (t->isMutable() && !t->isShared()));
    }
    else if (isWild())
    {
        if (isShared())
            t = sto;            // shared wild => shared
        else
            t = wto;            // wild => naked
        assert(!t || t->isMutable());
    }
    if (!t)
    {
        t = makeMutable();
        t = t->merge();
        t->fixTo(this);
    }
    else
        t = t->merge();
    assert(t->isMutable());
    return t;
}

Type *Type::sharedOf()
{
    //printf("Type::sharedOf() %p, %s\n", this, toChars());
    if (mod == MODshared)
    {
        return this;
    }
    if (sto)
    {
        assert(sto->isShared());
        return sto;
    }
    Type *t = makeShared();
    t = t->merge();
    t->fixTo(this);
    //printf("\t%p\n", t);
    return t;
}

Type *Type::sharedConstOf()
{
    //printf("Type::sharedConstOf() %p, %s\n", this, toChars());
    if (mod == (MODshared | MODconst))
    {
        return this;
    }
    if (scto)
    {
        assert(scto->mod == (MODshared | MODconst));
        return scto;
    }
    Type *t = makeSharedConst();
    t = t->merge();
    t->fixTo(this);
    //printf("\t%p\n", t);
    return t;
}


/********************************
 * Make type unshared.
 *      0            => 0
 *      const        => const
 *      immutable    => immutable
 *      shared       => 0
 *      shared const => const
 *      wild         => wild
 *      shared wild  => wild
 */

Type *Type::unSharedOf()
{
    //printf("Type::unSharedOf() %p, %s\n", this, toChars());
    Type *t = this;

    if (isShared())
    {
        if (isConst())
            t = cto;    // shared const => const
        else if (isWild())
            t = wto;    // shared wild => wild
        else
            t = sto;
        assert(!t || !t->isShared());
    }

    if (!t)
    {
        t = this->nullAttributes();
        t->mod = mod & ~MODshared;
        t->ctype = ctype;
        t = t->merge();

        t->fixTo(this);
    }
    else
        t = t->merge();
    assert(!t->isShared());
    return t;
}

/********************************
 * Convert to 'wild'.
 */

Type *Type::wildOf()
{
    //printf("Type::wildOf() %p %s\n", this, toChars());
    if (mod == MODwild)
    {
        return this;
    }
    if (wto)
    {
        assert(wto->isWild());
        return wto;
    }
    Type *t = makeWild();
    t = t->merge();
    t->fixTo(this);
    //printf("\t%p %s\n", t, t->toChars());
    return t;
}

Type *Type::sharedWildOf()
{
    //printf("Type::sharedWildOf() %p, %s\n", this, toChars());
    if (mod == (MODshared | MODwild))
    {
        return this;
    }
    if (swto)
    {
        assert(swto->mod == (MODshared | MODwild));
        return swto;
    }
    Type *t = makeSharedWild();
    t = t->merge();
    t->fixTo(this);
    //printf("\t%p\n", t);
    return t;
}

/**********************************
 * For our new type 'this', which is type-constructed from t,
 * fill in the cto, ito, sto, scto, wto shortcuts.
 */

void Type::fixTo(Type *t)
{
    ito = t->ito;
#if 0
    /* Cannot do these because these are not fully transitive:
     * there can be a shared ptr to immutable, for example.
     * Immutable subtypes are always immutable, though.
     */
    cto = t->cto;
    sto = t->sto;
    scto = t->scto;
#endif

    assert(mod != t->mod);
#define X(m, n) (((m) << 4) | (n))
    switch (X(mod, t->mod))
    {
        case X(0, MODconst):
            cto = t;
            break;

        case X(0, MODimmutable):
            ito = t;
            break;

        case X(0, MODshared):
            sto = t;
            break;

        case X(0, MODshared | MODconst):
            scto = t;
            break;

        case X(0, MODwild):
            wto = t;
            break;

        case X(0, MODshared | MODwild):
            swto = t;
            break;


        case X(MODconst, 0):
            cto = NULL;
            goto L2;

        case X(MODconst, MODimmutable):
            ito = t;
            goto L2;

        case X(MODconst, MODshared):
            sto = t;
            goto L2;

        case X(MODconst, MODshared | MODconst):
            scto = t;
            goto L2;

        case X(MODconst, MODwild):
            wto = t;
            goto L2;

        case X(MODconst, MODshared | MODwild):
            swto = t;
        L2:
            t->cto = this;
            break;


        case X(MODimmutable, 0):
            ito = NULL;
            goto L3;

        case X(MODimmutable, MODconst):
            cto = t;
            goto L3;

        case X(MODimmutable, MODshared):
            sto = t;
            goto L3;

        case X(MODimmutable, MODshared | MODconst):
            scto = t;
            goto L3;

        case X(MODimmutable, MODwild):
            wto = t;
            goto L3;

        case X(MODimmutable, MODshared | MODwild):
            swto = t;
        L3:
            t->ito = this;
            if (t->cto) t->cto->ito = this;
            if (t->sto) t->sto->ito = this;
            if (t->scto) t->scto->ito = this;
            if (t->wto) t->wto->ito = this;
            if (t->swto) t->swto->ito = this;
            break;


        case X(MODshared, 0):
            sto = NULL;
            goto L4;

        case X(MODshared, MODconst):
            cto = t;
            goto L4;

        case X(MODshared, MODimmutable):
            ito = t;
            goto L4;

        case X(MODshared, MODshared | MODconst):
            scto = t;
            goto L4;

        case X(MODshared, MODwild):
            wto = t;
            goto L4;

        case X(MODshared, MODshared | MODwild):
            swto = t;
        L4:
            t->sto = this;
            break;


        case X(MODshared | MODconst, 0):
            scto = NULL;
            goto L5;

        case X(MODshared | MODconst, MODconst):
            cto = t;
            goto L5;

        case X(MODshared | MODconst, MODimmutable):
            ito = t;
            goto L5;

        case X(MODshared | MODconst, MODwild):
            wto = t;
            goto L5;

        case X(MODshared | MODconst, MODshared):
            sto = t;
            goto L5;

        case X(MODshared | MODconst, MODshared | MODwild):
            swto = t;
        L5:
            t->scto = this;
            break;


        case X(MODwild, 0):
            wto = NULL;
            goto L6;

        case X(MODwild, MODconst):
            cto = t;
            goto L6;

        case X(MODwild, MODimmutable):
            ito = t;
            goto L6;

        case X(MODwild, MODshared):
            sto = t;
            goto L6;

        case X(MODwild, MODshared | MODconst):
            scto = t;
            goto L6;

        case X(MODwild, MODshared | MODwild):
            swto = t;
        L6:
            t->wto = this;
            break;


        case X(MODshared | MODwild, 0):
            swto = NULL;
            goto L7;

        case X(MODshared | MODwild, MODconst):
            cto = t;
            goto L7;

        case X(MODshared | MODwild, MODimmutable):
            ito = t;
            goto L7;

        case X(MODshared | MODwild, MODshared):
            sto = t;
            goto L7;

        case X(MODshared | MODwild, MODshared | MODconst):
            scto = t;
            goto L7;

        case X(MODshared | MODwild, MODwild):
            wto = t;
        L7:
            t->swto = this;
            break;


        default:
            assert(0);
    }
#undef X

    check();
    t->check();
    //printf("fixTo: %s, %s\n", toChars(), t->toChars());
}

/***************************
 * Look for bugs in constructing types.
 */

void Type::check()
{
    switch (mod)
    {
        case 0:
            if (cto) assert(cto->mod == MODconst);
            if (ito) assert(ito->mod == MODimmutable);
            if (sto) assert(sto->mod == MODshared);
            if (scto) assert(scto->mod == (MODshared | MODconst));
            if (wto) assert(wto->mod == MODwild);
            if (swto) assert(swto->mod == (MODshared | MODwild));
            break;

        case MODconst:
            if (cto) assert(cto->mod == 0);
            if (ito) assert(ito->mod == MODimmutable);
            if (sto) assert(sto->mod == MODshared);
            if (scto) assert(scto->mod == (MODshared | MODconst));
            if (wto) assert(wto->mod == MODwild);
            if (swto) assert(swto->mod == (MODshared | MODwild));
            break;

        case MODimmutable:
            if (cto) assert(cto->mod == MODconst);
            if (ito) assert(ito->mod == 0);
            if (sto) assert(sto->mod == MODshared);
            if (scto) assert(scto->mod == (MODshared | MODconst));
            if (wto) assert(wto->mod == MODwild);
            if (swto) assert(swto->mod == (MODshared | MODwild));
            break;

        case MODshared:
            if (cto) assert(cto->mod == MODconst);
            if (ito) assert(ito->mod == MODimmutable);
            if (sto) assert(sto->mod == 0);
            if (scto) assert(scto->mod == (MODshared | MODconst));
            if (wto) assert(wto->mod == MODwild);
            if (swto) assert(swto->mod == (MODshared | MODwild));
            break;

        case MODshared | MODconst:
            if (cto) assert(cto->mod == MODconst);
            if (ito) assert(ito->mod == MODimmutable);
            if (sto) assert(sto->mod == MODshared);
            if (scto) assert(scto->mod == 0);
            if (wto) assert(wto->mod == MODwild);
            if (swto) assert(swto->mod == (MODshared | MODwild));
            break;

        case MODwild:
            if (cto) assert(cto->mod == MODconst);
            if (ito) assert(ito->mod == MODimmutable);
            if (sto) assert(sto->mod == MODshared);
            if (scto) assert(scto->mod == (MODshared | MODconst));
            if (wto) assert(wto->mod == 0);
            if (swto) assert(swto->mod == (MODshared | MODwild));
            break;

        case MODshared | MODwild:
            if (cto) assert(cto->mod == MODconst);
            if (ito) assert(ito->mod == MODimmutable);
            if (sto) assert(sto->mod == MODshared);
            if (scto) assert(scto->mod == (MODshared | MODconst));
            if (wto) assert(wto->mod == MODwild);
            if (swto) assert(swto->mod == 0);
            break;

        default:
            assert(0);
    }

    Type *tn = nextOf();
    if (tn && ty != Tfunction && tn->ty != Tfunction && ty != Tenum)
    {   // Verify transitivity
        switch (mod)
        {
            case 0:
                break;

            case MODconst:
                assert(tn->mod & MODimmutable || tn->mod & MODconst);
                break;

            case MODimmutable:
                assert(tn->mod == MODimmutable);
                break;

            case MODshared:
                assert(tn->mod & MODimmutable || tn->mod & MODshared);
                break;

            case MODshared | MODconst:
                assert(tn->mod & MODimmutable || tn->mod & (MODshared | MODconst));
                break;

            case MODwild:
                assert(tn->mod);
                break;

            case MODshared | MODwild:
                assert(tn->mod == MODimmutable || tn->mod == (MODshared | MODconst) || tn->mod == (MODshared | MODwild));
                break;

            default:
                assert(0);
        }
        tn->check();
    }
}

Type *Type::makeConst()
{
    //printf("Type::makeConst() %p, %s\n", this, toChars());
    if (cto) return cto;
    Type *t = this->nullAttributes();
    t->mod = MODconst;
    //printf("-Type::makeConst() %p, %s\n", t, toChars());
    return t;
}

Type *Type::makeInvariant()
{
    if (ito) return ito;
    Type *t = this->nullAttributes();
    t->mod = MODimmutable;
    return t;
}

Type *Type::makeShared()
{
    if (sto) return sto;
    Type *t = this->nullAttributes();
    t->mod = MODshared;
    return t;
}

Type *Type::makeSharedConst()
{
    if (scto) return scto;
    Type *t = this->nullAttributes();
    t->mod = MODshared | MODconst;
    return t;
}

Type *Type::makeWild()
{
    if (wto) return wto;
    Type *t = this->nullAttributes();
    t->mod = MODwild;
    return t;
}

Type *Type::makeSharedWild()
{
    if (swto) return swto;
    Type *t = this->nullAttributes();
    t->mod = MODshared | MODwild;
    return t;
}

Type *Type::makeMutable()
{
    Type *t = this->nullAttributes();
    t->mod = mod & MODshared;
    return t;
}

/*************************************
 * Apply STCxxxx bits to existing type.
 * Use *before* semantic analysis is run.
 */

Type *Type::addSTC(StorageClass stc)
{   Type *t = this;

    if (stc & STCconst)
    {   if (t->isShared())
            t = t->makeSharedConst();
        else
            t = t->makeConst();
    }
    if (stc & STCimmutable)
        t = t->makeInvariant();
    if (stc & STCshared)
    {   if (t->isConst())
            t = t->makeSharedConst();
        else
            t = t->makeShared();
    }
    if (stc & STCwild)
    {   if (t->isShared())
            t = t->makeSharedWild();
        else
            t = t->makeWild();
    }
    return t;
}

/************************************
 * Apply MODxxxx bits to existing type.
 */

Type *Type::castMod(unsigned mod)
{   Type *t;

    switch (mod)
    {
        case 0:
            t = unSharedOf()->mutableOf();
            break;

        case MODconst:
            t = unSharedOf()->constOf();
            break;

        case MODimmutable:
            t = immutableOf();
            break;

        case MODshared:
            t = mutableOf()->sharedOf();
            break;

        case MODshared | MODconst:
            t = sharedConstOf();
            break;

        case MODwild:
            t = unSharedOf()->wildOf();
            break;

        case MODshared | MODwild:
            t = sharedWildOf();
            break;

        default:
            assert(0);
    }
    return t;
}

/************************************
 * Add MODxxxx bits to existing type.
 * We're adding, not replacing, so adding const to
 * a shared type => "shared const"
 */

Type *Type::addMod(unsigned mod)
{   Type *t = this;

    /* Add anything to immutable, and it remains immutable
     */
    if (!t->isImmutable())
    {
        //printf("addMod(%x) %s\n", mod, toChars());
        switch (mod)
        {
            case 0:
                break;

            case MODconst:
                if (isShared())
                    t = sharedConstOf();
                else
                    t = constOf();
                break;

            case MODimmutable:
                t = immutableOf();
                break;

            case MODshared:
                if (isConst())
                    t = sharedConstOf();
                else if (isWild())
                    t = sharedWildOf();
                else
                    t = sharedOf();
                break;

            case MODshared | MODconst:
                t = sharedConstOf();
                break;

            case MODwild:
                if (isConst())
                    ;
                else if (isShared())
                    t = sharedWildOf();
                else
                    t = wildOf();
                break;

            case MODshared | MODwild:
                if (isConst())
                    t = sharedConstOf();
                else
                    t = sharedWildOf();
                break;

            default:
                assert(0);
        }
    }
    return t;
}

/************************************
 * Add storage class modifiers to type.
 */

Type *Type::addStorageClass(StorageClass stc)
{
    /* Just translate to MOD bits and let addMod() do the work
     */
    unsigned mod = 0;

    if (stc & STCimmutable)
        mod = MODimmutable;
    else
    {   if (stc & (STCconst | STCin))
            mod = MODconst;
        else if (stc & STCwild)         // const takes precedence over wild
            mod |= MODwild;
        if (stc & STCshared)
            mod |= MODshared;
    }
    return addMod(mod);
}

Type *Type::pointerTo()
{
    if (ty == Terror)
        return this;
    if (!pto)
    {   Type *t;

        t = new TypePointer(this);
        pto = t->merge();
    }
    return pto;
}

Type *Type::referenceTo()
{
    if (ty == Terror)
        return this;
    if (!rto)
    {   Type *t;

        t = new TypeReference(this);
        rto = t->merge();
    }
    return rto;
}

Type *Type::arrayOf()
{
    if (ty == Terror)
        return this;
    if (!arrayof)
    {   Type *t;

        t = new TypeDArray(this);
        arrayof = t->merge();
    }
    return arrayof;
}

Type *Type::aliasthisOf()
{
    AggregateDeclaration *ad = NULL;
    if (ty == Tclass)
    {
        ad = ((TypeClass *)this)->sym;
        goto L1;
    }
    else if (ty == Tstruct)
    {
        ad = ((TypeStruct *)this)->sym;
    L1:
        if (!ad->aliasthis)
            return NULL;

        Declaration *d = ad->aliasthis->isDeclaration();
        if (d)
        {   assert(d->type);
            Type *t = d->type;
            if (d->isVarDeclaration() && d->needThis())
            {
                t = t->addMod(this->mod);
            }
            else if (d->isFuncDeclaration())
            {
                FuncDeclaration *fd = resolveFuncCall(Loc(), NULL, d, NULL, this, NULL, 1);
                if (fd && fd->functionSemantic())
                {
                    t = fd->type->nextOf();
                    t = t->substWildTo(mod == 0 ? MODmutable : mod);
                }
                else
                    return Type::terror;
            }
            return t;
        }
        EnumDeclaration *ed = ad->aliasthis->isEnumDeclaration();
        if (ed)
        {
            Type *t = ed->type;
            return t;
        }
        TemplateDeclaration *td = ad->aliasthis->isTemplateDeclaration();
        if (td)
        {   assert(td->scope);
            FuncDeclaration *fd = resolveFuncCall(Loc(), NULL, td, NULL, this, NULL, 1);
            if (fd && fd->functionSemantic())
            {
                Type *t = fd->type->nextOf();
                t = t->substWildTo(mod == 0 ? MODmutable : mod);
                return t;
            }
            else
                return Type::terror;
        }
        //printf("%s\n", ad->aliasthis->kind());
    }
    return NULL;
}

int Type::checkAliasThisRec()
{
    Type *tb = toBasetype();
    AliasThisRec* pflag;
    if (tb->ty == Tstruct)
        pflag = &((TypeStruct *)tb)->att;
    else if (tb->ty == Tclass)
        pflag = &((TypeClass *)tb)->att;
    else
        return 0;

    AliasThisRec flag = (AliasThisRec)(*pflag & ~RECtracing);
    if (flag == RECfwdref)
    {
        Type *att = aliasthisOf();
        flag = att && att->implicitConvTo(this) ? RECyes : RECno;
    }
    *pflag = (AliasThisRec)(flag | (*pflag & RECtracing));
    return flag == RECyes;
}

Dsymbol *Type::toDsymbol(Scope *sc)
{
    return NULL;
}

/*******************************
 * If this is a shell around another type,
 * get that other type.
 */

Type *Type::toBasetype()
{
    return this;
}

/***************************
 * Return !=0 if modfrom can be implicitly converted to modto
 */
int MODimplicitConv(unsigned char modfrom, unsigned char modto)
{
    if (modfrom == modto)
        return 1;

    //printf("MODimplicitConv(from = %x, to = %x)\n", modfrom, modto);
    #define X(m, n) (((m) << 4) | (n))
    switch (X(modfrom, modto))
    {
        case X(0,            MODconst):
        case X(MODimmutable, MODconst):
        case X(MODwild,      MODconst):
        case X(MODimmutable, MODconst | MODshared):
        case X(MODshared,    MODconst | MODshared):
        case X(MODwild | MODshared,    MODconst | MODshared):
            return 1;

        default:
            return 0;
    }
    #undef X
}

/***************************
 * Return !=0 if a method of type '() modfrom' can call a method of type '() modto'.
 */
int MODmethodConv(unsigned char modfrom, unsigned char modto)
{
    if (MODimplicitConv(modfrom, modto))
        return 1;

    #define X(m, n) (((m) << 4) | (n))
    switch (X(modfrom, modto))
    {
        case X(0, MODwild):
        case X(MODimmutable, MODwild):
        case X(MODconst, MODwild):
        case X(MODshared, MODshared|MODwild):
        case X(MODshared|MODimmutable, MODshared|MODwild):
        case X(MODshared|MODconst, MODshared|MODwild):
            return 1;

        default:
            return 0;
    }
    #undef X
}

/***************************
 * Merge mod bits to form common mod.
 */
int MODmerge(unsigned char mod1, unsigned char mod2)
{
    if (mod1 == mod2)
        return mod1;

    //printf("MODmerge(1 = %x, 2 = %x)\n", modfrom, modto);
    #define X(m, n) (((m) << 4) | (n))
    // cases are commutative
    #define Y(m, n) X(m, n): case X(n, m)
    switch (X(mod1, mod2))
    {
#if 0
        case X(0, 0):
        case X(MODconst, MODconst):
        case X(MODimmutable, MODimmutable):
        case X(MODshared, MODshared):
        case X(MODshared | MODconst, MODshared | MODconst):
        case X(MODwild, MODwild):
        case X(MODshared | MODwild, MODshared | MODwild):
#endif

        case Y(0, MODconst):
        case Y(0, MODimmutable):
        case Y(MODconst, MODimmutable):
        case Y(MODconst, MODwild):
        case Y(0, MODwild):
        case Y(MODimmutable, MODwild):
            return MODconst;

        case Y(0, MODshared):
            return MODshared;

        case Y(0, MODshared | MODconst):
        case Y(MODconst, MODshared):
        case Y(MODconst, MODshared | MODconst):
        case Y(MODimmutable, MODshared):
        case Y(MODimmutable, MODshared | MODconst):
        case Y(MODshared, MODshared | MODconst):
        case Y(0, MODshared | MODwild):
        case Y(MODconst, MODshared | MODwild):
        case Y(MODimmutable, MODshared | MODwild):
        case Y(MODshared, MODwild):
        case Y(MODshared, MODshared | MODwild):
        case Y(MODshared | MODconst, MODwild):
        case Y(MODshared | MODconst, MODshared | MODwild):
            return MODshared | MODconst;

        case Y(MODwild, MODshared | MODwild):
            return MODshared | MODwild;

        default:
            assert(0);
    }
    #undef Y
    #undef X
    assert(0);
    return 0;
}

/*********************************
 * Mangling for mod.
 */
void MODtoDecoBuffer(OutBuffer *buf, unsigned char mod)
{
    switch (mod)
    {   case 0:
            break;
        case MODconst:
            buf->writeByte('x');
            break;
        case MODimmutable:
            buf->writeByte('y');
            break;
        case MODshared:
            buf->writeByte('O');
            break;
        case MODshared | MODconst:
            buf->writestring("Ox");
            break;
        case MODwild:
            buf->writestring("Ng");
            break;
        case MODshared | MODwild:
            buf->writestring("ONg");
            break;
        default:
            assert(0);
    }
}

/*********************************
 * Store modifier name into buf.
 */
void MODtoBuffer(OutBuffer *buf, unsigned char mod)
{
    switch (mod)
    {   case 0:
            break;

        case MODimmutable:
            buf->writestring(Token::tochars[TOKimmutable]);
            break;

        case MODshared:
            buf->writestring(Token::tochars[TOKshared]);
            break;

        case MODshared | MODconst:
            buf->writestring(Token::tochars[TOKshared]);
            buf->writeByte(' ');
        case MODconst:
            buf->writestring(Token::tochars[TOKconst]);
            break;

        case MODshared | MODwild:
            buf->writestring(Token::tochars[TOKshared]);
            buf->writeByte(' ');
        case MODwild:
            buf->writestring(Token::tochars[TOKwild]);
            break;
        default:
            assert(0);
    }
}


/*********************************
 * Return modifier name.
 */
char *MODtoChars(unsigned char mod)
{
    OutBuffer buf;
    buf.reserve(16);
    MODtoBuffer(&buf, mod);
    buf.writebyte(0);
    return buf.extractData();
}

/********************************
 * Name mangling.
 * Input:
 *      flag    0x100   do not do const/invariant
 */

void Type::toDecoBuffer(OutBuffer *buf, int flag)
{
    if (flag != mod && flag != 0x100)
    {
        MODtoDecoBuffer(buf, mod);
    }
    buf->writeByte(mangleChar[ty]);
}

/********************************
 * For pretty-printing a type.
 */

char *Type::toChars()
{   OutBuffer buf;
    buf.reserve(16);
    HdrGenState hgs;

    toCBuffer(&buf, NULL, &hgs);
    buf.writebyte(0);
    return buf.extractData();
}

void Type::toCBuffer(OutBuffer *buf, Identifier *ident, HdrGenState *hgs)
{
    toCBuffer2(buf, hgs, 0);
    if (ident)
    {   buf->writeByte(' ');
        buf->writestring(ident->toChars());
    }
}

void Type::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    buf->writestring(toChars());
}

void Type::toCBuffer3(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    if (mod != this->mod)
    {
        if (!(mod & MODshared) && (this->mod & MODshared))
        {
            MODtoBuffer(buf, this->mod & MODshared);
            buf->writeByte('(');
        }
        int m1 = this->mod & ~MODshared;
        int m2 = (mod ^ m1) & m1;
        if (m2)
        {
            MODtoBuffer(buf, m2);
            buf->writeByte('(');
            toCBuffer2(buf, hgs, this->mod);
            buf->writeByte(')');
        }
        else
            toCBuffer2(buf, hgs, this->mod);
        if (!(mod & MODshared) && (this->mod & MODshared))
        {
            buf->writeByte(')');
        }
    }
}

/*********************************
 * Store this type's modifier name into buf.
 */
void Type::modToBuffer(OutBuffer *buf)
{
    if (mod)
    {
        buf->writeByte(' ');
        MODtoBuffer(buf, mod);
    }
}

/*********************************
 * Return this type's modifier name.
 */
char *Type::modToChars()
{
    OutBuffer buf;
    buf.reserve(16);
    modToBuffer(&buf);
    buf.writebyte(0);
    return buf.extractData();
}

/************************************
 */

Type *Type::merge()
{
    if (ty == Terror) return this;
    if (ty == Ttypeof) return this;
    if (ty == Tident) return this;
    if (ty == Tinstance) return this;
    if (ty == Taarray && !((TypeAArray *)this)->index->merge()->deco)
        return this;
    if (ty != Tenum && nextOf() && !nextOf()->deco)
        return this;

    //printf("merge(%s)\n", toChars());
    Type *t = this;
    assert(t);
    if (!deco)
    {
        OutBuffer buf;
        buf.reserve(32);

        //if (next)
            //next = next->merge();
        toDecoBuffer(&buf);
        StringValue *sv = stringtable.update((char *)buf.data, buf.offset);
        if (sv->ptrvalue)
        {   t = (Type *) sv->ptrvalue;
#ifdef DEBUG
            if (!t->deco)
                printf("t = %s\n", t->toChars());
#endif
            assert(t->deco);
            //printf("old value, deco = '%s' %p\n", t->deco, t->deco);
        }
        else
        {
            sv->ptrvalue = this;
            deco = (char *)sv->toDchars();
            //printf("new value, deco = '%s' %p\n", t->deco, t->deco);
        }
    }
    return t;
}

/*************************************
 * This version does a merge even if the deco is already computed.
 * Necessary for types that have a deco, but are not merged.
 */
Type *Type::merge2()
{
    //printf("merge2(%s)\n", toChars());
    Type *t = this;
    assert(t);
    if (!t->deco)
        return t->merge();

    StringValue *sv = stringtable.lookup((char *)t->deco, strlen(t->deco));
    if (sv && sv->ptrvalue)
    {   t = (Type *) sv->ptrvalue;
        assert(t->deco);
    }
    else
        assert(0);
    return t;
}

int Type::isintegral()
{
    return FALSE;
}

int Type::isfloating()
{
    return FALSE;
}

int Type::isreal()
{
    return FALSE;
}

int Type::isimaginary()
{
    return FALSE;
}

int Type::iscomplex()
{
    return FALSE;
}

int Type::isscalar()
{
    return FALSE;
}

int Type::isunsigned()
{
    return FALSE;
}

ClassDeclaration *Type::isClassHandle()
{
    return NULL;
}

int Type::isscope()
{
    return FALSE;
}

int Type::isString()
{
    return FALSE;
}

/**************************
 * When T is mutable,
 * Given:
 *      T a, b;
 * Can we bitwise assign:
 *      a = b;
 * ?
 */
int Type::isAssignable()
{
    return TRUE;
}

int Type::checkBoolean()
{
    return isscalar();
}

/********************************
 * TRUE if when type goes out of scope, it needs a destructor applied.
 * Only applies to value types, not ref types.
 */
int Type::needsDestruction()
{
    return FALSE;
}

/*********************************
 *
 */

bool Type::needsNested()
{
    return false;
}

/*********************************
 * Check type to see if it is based on a deprecated symbol.
 */

void Type::checkDeprecated(Loc loc, Scope *sc)
{
    Dsymbol *s = toDsymbol(sc);

    if (s)
        s->checkDeprecated(loc, sc);
}


Expression *Type::defaultInit(Loc loc)
{
#if LOGDEFAULTINIT
    printf("Type::defaultInit() '%s'\n", toChars());
#endif
    return NULL;
}

/***************************************
 * Use when we prefer the default initializer to be a literal,
 * rather than a global immutable variable.
 */
Expression *Type::defaultInitLiteral(Loc loc)
{
#if LOGDEFAULTINIT
    printf("Type::defaultInitLiteral() '%s'\n", toChars());
#endif
    return defaultInit(loc);
}

int Type::isZeroInit(Loc loc)
{
    return 0;           // assume not
}

int Type::isBaseOf(Type *t, int *poffset)
{
    return 0;           // assume not
}

/********************************
 * Determine if 'this' can be implicitly converted
 * to type 'to'.
 * Returns:
 *      MATCHnomatch, MATCHconvert, MATCHconst, MATCHexact
 */

MATCH Type::implicitConvTo(Type *to)
{
    //printf("Type::implicitConvTo(this=%p, to=%p)\n", this, to);
    //printf("from: %s\n", toChars());
    //printf("to  : %s\n", to->toChars());
    if (this == to)
        return MATCHexact;
    return MATCHnomatch;
}

/*******************************
 * Determine if converting 'this' to 'to' is an identity operation,
 * a conversion to const operation, or the types aren't the same.
 * Returns:
 *      MATCHexact      'this' == 'to'
 *      MATCHconst      'to' is const
 *      MATCHnomatch    conversion to mutable or invariant
 */

MATCH Type::constConv(Type *to)
{
    //printf("Type::constConv(this = %s, to = %s)\n", toChars(), to->toChars());
    if (equals(to))
        return MATCHexact;
    if (ty == to->ty && MODimplicitConv(mod, to->mod))
        return MATCHconst;
    return MATCHnomatch;
}

/***************************************
 * Return MOD bits matching this type to wild parameter type (tprm).
 */

unsigned Type::wildConvTo(Type *tprm)
{
    //printf("Type::wildConvTo this = '%s', tprm = '%s'\n", toChars(), tprm->toChars());

    if (tprm->isWild() && implicitConvTo(tprm->substWildTo(MODconst)))
    {
        if (isWild())
            return MODwild;
        else if (isConst())
            return MODconst;
        else if (isImmutable())
            return MODimmutable;
        else if (isMutable())
            return MODmutable;
        else
            assert(0);
    }
    return 0;
}

Type *Type::substWildTo(unsigned mod)
{
    //printf("+Type::substWildTo this = %s, mod = x%x\n", toChars(), mod);
    Type *t;

    if (nextOf())
    {
        t = nextOf()->substWildTo(mod);
        if (t == nextOf())
            t = this;
        else
        {
            if (ty == Tpointer)
                t = t->pointerTo();
            else if (ty == Tarray)
                t = t->arrayOf();
            else if (ty == Tsarray)
                t = new TypeSArray(t, ((TypeSArray *)this)->dim->syntaxCopy());
            else if (ty == Taarray)
            {
                t = new TypeAArray(t, ((TypeAArray *)this)->index->syntaxCopy());
                ((TypeAArray *)t)->sc = ((TypeAArray *)this)->sc;   // duplicate scope
            }
            else
                assert(0);

            t = t->merge();
        }
    }
    else
        t = this;

    if (isWild())
    {
        if (mod & MODconst)
            t = isShared() ? t->sharedConstOf() : t->constOf();
        else if (mod & MODimmutable)
            t = t->immutableOf();
        else if (mod & MODwild)
            t = isShared() ? t->sharedWildOf() : t->wildOf();
        else
            t = isShared() ? t->sharedOf() : t->mutableOf();
    }

    //printf("-Type::substWildTo t = %s\n", t->toChars());
    return t;
}

/**************************
 * Return type with the top level of it being mutable.
 */
Type *Type::toHeadMutable()
{
    if (!mod)
        return this;
    return mutableOf();
}

/***************************************
 * Calculate built-in properties which just the type is necessary.
 *
 * If flag == 1, don't report "not a property" error and just return NULL.
 */
Expression *Type::getProperty(Loc loc, Identifier *ident, int flag)
{   Expression *e;

#if LOGDOTEXP
    printf("Type::getProperty(type = '%s', ident = '%s')\n", toChars(), ident->toChars());
#endif
    if (ident == Id::__sizeof)
    {
        d_uns64 sz = size(loc);
        if (sz == SIZE_INVALID)
            return new ErrorExp();
        e = new IntegerExp(loc, sz, Type::tsize_t);
    }
    else if (ident == Id::__xalignof)
    {
        e = new IntegerExp(loc, alignsize(), Type::tsize_t);
    }
    else if (ident == Id::typeinfo)
    {
        error(loc, ".typeinfo deprecated, use typeid(type)");
        e = getTypeInfo(NULL);
    }
    else if (ident == Id::init)
    {
        Type *tb = toBasetype();
        e = defaultInitLiteral(loc);
        if (tb->ty == Tstruct && tb->needsNested())
        {
            StructLiteralExp *se = (StructLiteralExp *)e;
            se->sinit = se->sd->toInitializer();
        }
    }
    else if (ident == Id::mangleof)
    {
        if (!deco)
        {
            error(loc, "forward reference of type %s.mangleof", toChars());
            e = new ErrorExp();
        }
        else
        {
            e = new StringExp(loc, (char *)deco, strlen(deco), 'c');
            Scope sc;
            e = e->semantic(&sc);
        }
    }
    else if (ident == Id::stringof)
    {   char *s = toChars();
        e = new StringExp(loc, s, strlen(s), 'c');
        Scope sc;
        e = e->semantic(&sc);
    }
    else if (flag && this != Type::terror)
    {
        return NULL;
    }
    else
    {
        Dsymbol *s = NULL;
        if (ty == Tstruct || ty == Tclass || ty == Tenum || ty == Ttypedef)
            s = toDsymbol(NULL);
        if (s)
            s = s->search_correct(ident);
        if (this != Type::terror)
        {
            if (s)
                error(loc, "no property '%s' for type '%s', did you mean '%s'?", ident->toChars(), toChars(), s->toChars());
            else
                error(loc, "no property '%s' for type '%s'", ident->toChars(), toChars());
        }
        e = new ErrorExp();
    }
    return e;
}

/***************************************
 * Access the members of the object e. This type is same as e->type.
 *
 * If flag == 1, don't report "not a property" error and just return NULL.
 */
Expression *Type::dotExp(Scope *sc, Expression *e, Identifier *ident, int flag)
{   VarDeclaration *v = NULL;

#if LOGDOTEXP
    printf("Type::dotExp(e = '%s', ident = '%s')\n", e->toChars(), ident->toChars());
#endif
    Expression *ex = e;
    while (ex->op == TOKcomma)
        ex = ((CommaExp *)ex)->e2;
    if (ex->op == TOKdotvar)
    {
        DotVarExp *dv = (DotVarExp *)ex;
        v = dv->var->isVarDeclaration();
    }
    else if (ex->op == TOKvar)
    {
        VarExp *ve = (VarExp *)ex;
        v = ve->var->isVarDeclaration();
    }
    if (v)
    {
        if (ident == Id::offset)
        {
            error(e->loc, ".offset deprecated, use .offsetof");
            goto Loffset;
        }
        else if (ident == Id::offsetof)
        {
          Loffset:
            if (v->isField())
            {
                e = new IntegerExp(e->loc, v->offset, Type::tsize_t);
                return e;
            }
        }
        else if (ident == Id::init)
        {
            Type *tb = toBasetype();
            e = defaultInitLiteral(e->loc);
            if (tb->ty == Tstruct && tb->needsNested())
            {
                StructLiteralExp *se = (StructLiteralExp *)e;
                se->sinit = se->sd->toInitializer();
            }
            goto Lreturn;
        }
    }
    if (ident == Id::typeinfo)
    {
        error(e->loc, ".typeinfo deprecated, use typeid(type)");
        e = getTypeInfo(sc);
    }
    else if (ident == Id::stringof)
    {   /* Bugzilla 3796: this should demangle e->type->deco rather than
         * pretty-printing the type.
         */
        char *s = e->toChars();
        e = new StringExp(e->loc, s, strlen(s), 'c');
    }
    else
        e = getProperty(e->loc, ident, flag);

Lreturn:
    if (!flag || e)
        e = e->semantic(sc);
    return e;
}

/************************************
 * Return alignment to use for this type.
 */

structalign_t Type::alignment()
{
    return STRUCTALIGN_DEFAULT;
}

/***************************************
 * Figures out what to do with an undefined member reference
 * for classes and structs.
 *
 * If flag == 1, don't report "not a property" error and just return NULL.
 */
Expression *Type::noMember(Scope *sc, Expression *e, Identifier *ident, int flag)
{
    assert(ty == Tstruct || ty == Tclass);
    AggregateDeclaration *sym = toDsymbol(sc)->isAggregateDeclaration();
    assert(sym);

    if (ident != Id::__sizeof &&
        ident != Id::__xalignof &&
        ident != Id::init &&
        ident != Id::mangleof &&
        ident != Id::stringof &&
        ident != Id::offsetof)
    {
        /* Look for overloaded opDot() to see if we should forward request
         * to it.
         */
        Dsymbol *fd = search_function(sym, Id::opDot);
        if (fd)
        {   /* Rewrite e.ident as:
             *  e.opDot().ident
             */
            e = build_overload(e->loc, sc, e, NULL, fd);
            e = new DotIdExp(e->loc, e, ident);
            return e->semantic(sc);
        }

        /* Look for overloaded opDispatch to see if we should forward request
         * to it.
         */
        fd = search_function(sym, Id::opDispatch);
        if (fd)
        {
            /* Rewrite e.ident as:
             *  e.opDispatch!("ident")
             */
            TemplateDeclaration *td = fd->isTemplateDeclaration();
            if (!td)
            {
                fd->error("must be a template opDispatch(string s), not a %s", fd->kind());
                return new ErrorExp();
            }
            StringExp *se = new StringExp(e->loc, ident->toChars());
            Objects *tiargs = new Objects();
            tiargs->push(se);
            DotTemplateInstanceExp *dti = new DotTemplateInstanceExp(e->loc, e, Id::opDispatch, tiargs);
            dti->ti->tempdecl = td;

            unsigned errors = flag ? global.startGagging() : 0;
            Expression *e = dti->semanticY(sc, 0);
            if (flag && global.endGagging(errors))
                e = NULL;
            return e;
        }

        /* See if we should forward to the alias this.
         */
        if (sym->aliasthis)
        {   /* Rewrite e.ident as:
             *  e.aliasthis.ident
             */
            e = resolveAliasThis(sc, e);
            DotIdExp *die = new DotIdExp(e->loc, e, ident);
            return die->semanticY(sc, flag);
        }
    }

    return Type::dotExp(sc, e, ident, flag);
}

void Type::error(Loc loc, const char *format, ...)
{
    va_list ap;
    va_start(ap, format);
    ::verror(loc, format, ap);
    va_end( ap );
}

void Type::warning(Loc loc, const char *format, ...)
{
    va_list ap;
    va_start(ap, format);
    ::vwarning(loc, format, ap);
    va_end( ap );
}

Identifier *Type::getTypeInfoIdent(int internal)
{
    // _init_10TypeInfo_%s
    OutBuffer buf;
    buf.reserve(32);

    if (internal)
    {   buf.writeByte(mangleChar[ty]);
        if (ty == Tarray)
            buf.writeByte(mangleChar[((TypeArray *)this)->next->ty]);
    }
    else
        toDecoBuffer(&buf);

    size_t len = buf.offset;
    buf.writeByte(0);

    // Allocate buffer on stack, fail over to using malloc()
    char namebuf[40];
    size_t namelen = 19 + sizeof(len) * 3 + len + 1;
    char *name = namelen <= sizeof(namebuf) ? namebuf : (char *)malloc(namelen);
    assert(name);

    sprintf(name, "_D%lluTypeInfo_%s6__initZ", (unsigned long long) 9 + len, buf.data);
    //printf("name = %s\n", name);
    assert(strlen(name) < namelen);     // don't overflow the buffer

    size_t off = 0;
    if (global.params.isOSX || global.params.isWindows && !global.params.is64bit)
        ++off;                 // C mangling will add '_' back in
    Identifier *id = Lexer::idPool(name + off);

    if (name != namebuf)
        free(name);
    return id;
}

TypeBasic *Type::isTypeBasic()
{
    return NULL;
}


void Type::resolve(Loc loc, Scope *sc, Expression **pe, Type **pt, Dsymbol **ps)
{
    //printf("Type::resolve() %s, %d\n", toChars(), ty);
    Type *t = semantic(loc, sc);
    *pt = t;
    *pe = NULL;
    *ps = NULL;
}

/*******************************
 * tparams == NULL:
 *     If one of the subtypes of this type is a TypeIdentifier,
 *     i.e. it's an unresolved type, return that type.
 * tparams != NULL:
 *     Only when the TypeIdentifier is one of template parameters,
 *     return that type.
 */

Type *Type::reliesOnTident(TemplateParameters *tparams)
{
    return NULL;
}

/***************************************
 * Return !=0 if the type or any of its subtypes is wild.
 */

int Type::hasWild()
{
    return mod & MODwild;
}

/********************************
 * We've mistakenly parsed this as a type.
 * Redo it as an Expression.
 * NULL if cannot.
 */

Expression *Type::toExpression()
{
    return NULL;
}

/***************************************
 * Return !=0 if type has pointers that need to
 * be scanned by the GC during a collection cycle.
 */

int Type::hasPointers()
{
    //printf("Type::hasPointers() %s, %d\n", toChars(), ty);
    return FALSE;
}

/*************************************
 * If this is a type of something, return that something.
 */

Type *Type::nextOf()
{
    return NULL;
}

/****************************************
 * Return the mask that an integral type will
 * fit into.
 */
uinteger_t Type::sizemask()
{   uinteger_t m;

    switch (toBasetype()->ty)
    {
        case Tbool:     m = 1;                          break;
        case Tchar:
        case Tint8:
        case Tuns8:     m = 0xFF;                       break;
        case Twchar:
        case Tint16:
        case Tuns16:    m = 0xFFFFUL;                   break;
        case Tdchar:
        case Tint32:
        case Tuns32:    m = 0xFFFFFFFFUL;               break;
        case Tint64:
        case Tuns64:    m = 0xFFFFFFFFFFFFFFFFULL;      break;
        default:
                assert(0);
    }
    return m;
}

/* ============================= TypeError =========================== */

TypeError::TypeError()
        : Type(Terror)
{
}

Type *TypeError::syntaxCopy()
{
    // No semantic analysis done, no need to copy
    return this;
}

void TypeError::toCBuffer(OutBuffer *buf, Identifier *ident, HdrGenState *hgs)
{
    buf->writestring("_error_");
}

d_uns64 TypeError::size(Loc loc) { return SIZE_INVALID; }
Expression *TypeError::getProperty(Loc loc, Identifier *ident, int flag) { return new ErrorExp(); }
Expression *TypeError::dotExp(Scope *sc, Expression *e, Identifier *ident, int flag) { return new ErrorExp(); }
Expression *TypeError::defaultInit(Loc loc) { return new ErrorExp(); }
Expression *TypeError::defaultInitLiteral(Loc loc) { return new ErrorExp(); }

/* ============================= TypeNext =========================== */

TypeNext::TypeNext(TY ty, Type *next)
        : Type(ty)
{
    this->next = next;
}

void TypeNext::toDecoBuffer(OutBuffer *buf, int flag)
{
    Type::toDecoBuffer(buf, flag);
    assert(next != this);
    //printf("this = %p, ty = %d, next = %p, ty = %d\n", this, this->ty, next, next->ty);
    next->toDecoBuffer(buf, (flag & 0x100) ? 0 : mod);
}

void TypeNext::checkDeprecated(Loc loc, Scope *sc)
{
    Type::checkDeprecated(loc, sc);
    if (next)   // next can be NULL if TypeFunction and auto return type
        next->checkDeprecated(loc, sc);
}


Type *TypeNext::reliesOnTident(TemplateParameters *tparams)
{
    return next->reliesOnTident(tparams);
}

int TypeNext::hasWild()
{
    return mod & MODwild || (next && next->hasWild());
}


/*******************************
 * For TypeFunction, nextOf() can return NULL if the function return
 * type is meant to be inferred, and semantic() hasn't yet ben run
 * on the function. After semantic(), it must no longer be NULL.
 */

Type *TypeNext::nextOf()
{
    return next;
}

Type *TypeNext::makeConst()
{
    //printf("TypeNext::makeConst() %p, %s\n", this, toChars());
    if (cto)
    {   assert(cto->mod == MODconst);
        return cto;
    }
    TypeNext *t = (TypeNext *)Type::makeConst();
    if (ty != Tfunction && next->ty != Tfunction &&
        //(next->deco || next->ty == Tfunction) &&
        !next->isImmutable() && !next->isConst())
    {   if (next->isShared())
            t->next = next->sharedConstOf();
        else
            t->next = next->constOf();
    }
    if (ty == Taarray)
    {
        ((TypeAArray *)t)->impl = NULL;         // lazily recompute it
    }
    //printf("TypeNext::makeConst() returns %p, %s\n", t, t->toChars());
    return t;
}

Type *TypeNext::makeInvariant()
{
    //printf("TypeNext::makeInvariant() %s\n", toChars());
    if (ito)
    {   assert(ito->isImmutable());
        return ito;
    }
    TypeNext *t = (TypeNext *)Type::makeInvariant();
    if (ty != Tfunction && next->ty != Tfunction &&
        //(next->deco || next->ty == Tfunction) &&
        !next->isImmutable())
    {   t->next = next->immutableOf();
    }
    if (ty == Taarray)
    {
        ((TypeAArray *)t)->impl = NULL;         // lazily recompute it
    }
    return t;
}

Type *TypeNext::makeShared()
{
    //printf("TypeNext::makeShared() %s\n", toChars());
    if (sto)
    {   assert(sto->mod == MODshared);
        return sto;
    }
    TypeNext *t = (TypeNext *)Type::makeShared();
    if (ty != Tfunction && next->ty != Tfunction &&
        //(next->deco || next->ty == Tfunction) &&
        !next->isImmutable() && !next->isShared())
    {
        if (next->isConst())
            t->next = next->sharedConstOf();
        else if (next->isWild())
            t->next = next->sharedWildOf();
        else
            t->next = next->sharedOf();
    }
    if (ty == Taarray)
    {
        ((TypeAArray *)t)->impl = NULL;         // lazily recompute it
    }
    //printf("TypeNext::makeShared() returns %p, %s\n", t, t->toChars());
    return t;
}

Type *TypeNext::makeSharedConst()
{
    //printf("TypeNext::makeSharedConst() %s\n", toChars());
    if (scto)
    {   assert(scto->mod == (MODshared | MODconst));
        return scto;
    }
    TypeNext *t = (TypeNext *)Type::makeSharedConst();
    if (ty != Tfunction && next->ty != Tfunction &&
        //(next->deco || next->ty == Tfunction) &&
        !next->isImmutable() && !next->isSharedConst())
    {
        t->next = next->sharedConstOf();
    }
    if (ty == Taarray)
    {
        ((TypeAArray *)t)->impl = NULL;         // lazily recompute it
    }
    //printf("TypeNext::makeSharedConst() returns %p, %s\n", t, t->toChars());
    return t;
}

Type *TypeNext::makeWild()
{
    //printf("TypeNext::makeWild() %s\n", toChars());
    if (wto)
    {   assert(wto->mod == MODwild);
        return wto;
    }
    TypeNext *t = (TypeNext *)Type::makeWild();
    if (ty != Tfunction && next->ty != Tfunction &&
        //(next->deco || next->ty == Tfunction) &&
        !next->isImmutable() && !next->isConst() && !next->isWild())
    {
        if (next->isShared())
            t->next = next->sharedWildOf();
        else
            t->next = next->wildOf();
    }
    if (ty == Taarray)
    {
        ((TypeAArray *)t)->impl = NULL;         // lazily recompute it
    }
    //printf("TypeNext::makeWild() returns %p, %s\n", t, t->toChars());
    return t;
}

Type *TypeNext::makeSharedWild()
{
    //printf("TypeNext::makeSharedWild() %s\n", toChars());
    if (swto)
    {   assert(swto->isSharedWild());
        return swto;
    }
    TypeNext *t = (TypeNext *)Type::makeSharedWild();
    if (ty != Tfunction && next->ty != Tfunction &&
        //(next->deco || next->ty == Tfunction) &&
        !next->isImmutable() && !next->isSharedConst())
    {
        if (next->isConst())
            t->next = next->sharedConstOf();
        else
            t->next = next->sharedWildOf();
    }
    if (ty == Taarray)
    {
        ((TypeAArray *)t)->impl = NULL;         // lazily recompute it
    }
    //printf("TypeNext::makeSharedWild() returns %p, %s\n", t, t->toChars());
    return t;
}

Type *TypeNext::makeMutable()
{
    //printf("TypeNext::makeMutable() %p, %s\n", this, toChars());
    TypeNext *t = (TypeNext *)Type::makeMutable();
    if (ty == Tsarray)
    {
        t->next = next->mutableOf();
    }
    if (ty == Taarray)
    {
        ((TypeAArray *)t)->impl = NULL;         // lazily recompute it
    }
    //printf("TypeNext::makeMutable() returns %p, %s\n", t, t->toChars());
    return t;
}

MATCH TypeNext::constConv(Type *to)
{
    //printf("TypeNext::constConv from = %s, to = %s\n", toChars(), to->toChars());
    if (equals(to))
        return MATCHexact;

    if (!(ty == to->ty && MODimplicitConv(mod, to->mod)))
        return MATCHnomatch;

    Type *tn = to->nextOf();
    if (!(tn && next->ty == tn->ty))
        return MATCHnomatch;

    MATCH m;
    if (to->isConst())  // whole tail const conversion
    {   // Recursive shared level check
        m = next->constConv(tn);
        if (m == MATCHexact)
            m = MATCHconst;
    }
    else
    {   //printf("\tnext => %s, to->next => %s\n", next->toChars(), tn->toChars());
        m = next->equals(tn) ? MATCHconst : MATCHnomatch;
    }
    return m;
}

unsigned TypeNext::wildConvTo(Type *tprm)
{
    if (ty == Tfunction)
        return 0;

    unsigned mod = 0;
    Type *tn = tprm->nextOf();
    if (!tn)
        return 0;
    mod = next->wildConvTo(tn);
    if (!mod)
        mod = Type::wildConvTo(tprm);

    return mod;
}


void TypeNext::transitive()
{
    /* Invoke transitivity of type attributes
     */
    next = next->addMod(mod);
}

/* ============================= TypeBasic =========================== */

#define TFLAGSintegral  1
#define TFLAGSfloating  2
#define TFLAGSunsigned  4
#define TFLAGSreal      8
#define TFLAGSimaginary 0x10
#define TFLAGScomplex   0x20
#define TFLAGSvector    0x40    // valid for a SIMD vector type

TypeBasic::TypeBasic(TY ty)
        : Type(ty)
{   const char *d;
    unsigned flags;

    flags = 0;
    switch (ty)
    {
        case Tvoid:     d = Token::toChars(TOKvoid);
                        flags |= TFLAGSvector;
                        break;

        case Tint8:     d = Token::toChars(TOKint8);
                        flags |= TFLAGSintegral | TFLAGSvector;
                        break;

        case Tuns8:     d = Token::toChars(TOKuns8);
                        flags |= TFLAGSintegral | TFLAGSunsigned | TFLAGSvector;
                        break;

        case Tint16:    d = Token::toChars(TOKint16);
                        flags |= TFLAGSintegral | TFLAGSvector;
                        break;

        case Tuns16:    d = Token::toChars(TOKuns16);
                        flags |= TFLAGSintegral | TFLAGSunsigned | TFLAGSvector;
                        break;

        case Tint32:    d = Token::toChars(TOKint32);
                        flags |= TFLAGSintegral | TFLAGSvector;
                        break;

        case Tuns32:    d = Token::toChars(TOKuns32);
                        flags |= TFLAGSintegral | TFLAGSunsigned | TFLAGSvector;
                        break;

        case Tfloat32:  d = Token::toChars(TOKfloat32);
                        flags |= TFLAGSfloating | TFLAGSreal | TFLAGSvector;
                        break;

        case Tint64:    d = Token::toChars(TOKint64);
                        flags |= TFLAGSintegral | TFLAGSvector;
                        break;

        case Tuns64:    d = Token::toChars(TOKuns64);
                        flags |= TFLAGSintegral | TFLAGSunsigned | TFLAGSvector;
                        break;

        case Tint128:   d = Token::toChars(TOKint128);
                        flags |= TFLAGSintegral;
                        break;

        case Tuns128:   d = Token::toChars(TOKuns128);
                        flags |= TFLAGSintegral | TFLAGSunsigned;
                        break;

        case Tfloat64:  d = Token::toChars(TOKfloat64);
                        flags |= TFLAGSfloating | TFLAGSreal | TFLAGSvector;
                        break;

        case Tfloat80:  d = Token::toChars(TOKfloat80);
                        flags |= TFLAGSfloating | TFLAGSreal;
                        break;

        case Timaginary32: d = Token::toChars(TOKimaginary32);
                        flags |= TFLAGSfloating | TFLAGSimaginary;
                        break;

        case Timaginary64: d = Token::toChars(TOKimaginary64);
                        flags |= TFLAGSfloating | TFLAGSimaginary;
                        break;

        case Timaginary80: d = Token::toChars(TOKimaginary80);
                        flags |= TFLAGSfloating | TFLAGSimaginary;
                        break;

        case Tcomplex32: d = Token::toChars(TOKcomplex32);
                        flags |= TFLAGSfloating | TFLAGScomplex;
                        break;

        case Tcomplex64: d = Token::toChars(TOKcomplex64);
                        flags |= TFLAGSfloating | TFLAGScomplex;
                        break;

        case Tcomplex80: d = Token::toChars(TOKcomplex80);
                        flags |= TFLAGSfloating | TFLAGScomplex;
                        break;

        case Tbool:     d = "bool";
                        flags |= TFLAGSintegral | TFLAGSunsigned;
                        break;

        case Tascii:    d = Token::toChars(TOKchar);
                        flags |= TFLAGSintegral | TFLAGSunsigned;
                        break;

        case Twchar:    d = Token::toChars(TOKwchar);
                        flags |= TFLAGSintegral | TFLAGSunsigned;
                        break;

        case Tdchar:    d = Token::toChars(TOKdchar);
                        flags |= TFLAGSintegral | TFLAGSunsigned;
                        break;

        default:        assert(0);
    }
    this->dstring = d;
    this->flags = flags;
    merge();
}

const char *TypeBasic::kind()
{
    return dstring;
}

Type *TypeBasic::syntaxCopy()
{
    // No semantic analysis done on basic types, no need to copy
    return this;
}


char *TypeBasic::toChars()
{
    return Type::toChars();
}

void TypeBasic::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    //printf("TypeBasic::toCBuffer2(mod = %d, this->mod = %d)\n", mod, this->mod);
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    buf->writestring(dstring);
}

d_uns64 TypeBasic::size(Loc loc)
{   unsigned size;

    //printf("TypeBasic::size()\n");
    switch (ty)
    {
        case Tint8:
        case Tuns8:     size = 1;       break;
        case Tint16:
        case Tuns16:    size = 2;       break;
        case Tint32:
        case Tuns32:
        case Tfloat32:
        case Timaginary32:
                        size = 4;       break;
        case Tint64:
        case Tuns64:
        case Tfloat64:
        case Timaginary64:
                        size = 8;       break;
        case Tfloat80:
        case Timaginary80:
                        size = Target::realsize; break;
        case Tcomplex32:
                        size = 8;               break;
        case Tcomplex64:
        case Tint128:
        case Tuns128:
                        size = 16;              break;
        case Tcomplex80:
                        size = Target::realsize * 2; break;

        case Tvoid:
            //size = Type::size();      // error message
            size = 1;
            break;

        case Tbool:     size = 1;               break;
        case Tascii:    size = 1;               break;
        case Twchar:    size = 2;               break;
        case Tdchar:    size = 4;               break;

        default:
            assert(0);
            break;
    }
    //printf("TypeBasic::size() = %d\n", size);
    return size;
}

unsigned TypeBasic::alignsize()
{
    return Target::alignsize(this);
}


Expression *TypeBasic::getProperty(Loc loc, Identifier *ident, int flag)
{
    Expression *e;
    d_int64 ivalue;
#ifdef IN_GCC
    real_t    fvalue;
#else
    d_float80 fvalue;
#endif

    //printf("TypeBasic::getProperty('%s')\n", ident->toChars());
    if (ident == Id::max)
    {
        switch (ty)
        {
            case Tint8:         ivalue = 0x7F;          goto Livalue;
            case Tuns8:         ivalue = 0xFF;          goto Livalue;
            case Tint16:        ivalue = 0x7FFFUL;      goto Livalue;
            case Tuns16:        ivalue = 0xFFFFUL;      goto Livalue;
            case Tint32:        ivalue = 0x7FFFFFFFUL;  goto Livalue;
            case Tuns32:        ivalue = 0xFFFFFFFFUL;  goto Livalue;
            case Tint64:        ivalue = 0x7FFFFFFFFFFFFFFFLL;  goto Livalue;
            case Tuns64:        ivalue = 0xFFFFFFFFFFFFFFFFULL; goto Livalue;
            case Tbool:         ivalue = 1;             goto Livalue;
            case Tchar:         ivalue = 0xFF;          goto Livalue;
            case Twchar:        ivalue = 0xFFFFUL;      goto Livalue;
            case Tdchar:        ivalue = 0x10FFFFUL;    goto Livalue;

            case Tcomplex32:
            case Timaginary32:
            case Tfloat32:      fvalue = FLT_MAX;       goto Lfvalue;
            case Tcomplex64:
            case Timaginary64:
            case Tfloat64:      fvalue = DBL_MAX;       goto Lfvalue;
            case Tcomplex80:
            case Timaginary80:
            case Tfloat80:      fvalue = Port::ldbl_max; goto Lfvalue;
        }
    }
    else if (ident == Id::min)
    {
        switch (ty)
        {
            case Tint8:         ivalue = -128;          goto Livalue;
            case Tuns8:         ivalue = 0;             goto Livalue;
            case Tint16:        ivalue = -32768;        goto Livalue;
            case Tuns16:        ivalue = 0;             goto Livalue;
            case Tint32:        ivalue = -2147483647L - 1;      goto Livalue;
            case Tuns32:        ivalue = 0;                     goto Livalue;
            case Tint64:        ivalue = (-9223372036854775807LL-1LL);  goto Livalue;
            case Tuns64:        ivalue = 0;             goto Livalue;
            case Tbool:         ivalue = 0;             goto Livalue;
            case Tchar:         ivalue = 0;             goto Livalue;
            case Twchar:        ivalue = 0;             goto Livalue;
            case Tdchar:        ivalue = 0;             goto Livalue;

            case Tcomplex32:
            case Timaginary32:
            case Tfloat32:
            case Tcomplex64:
            case Timaginary64:
            case Tfloat64:
            case Tcomplex80:
            case Timaginary80:
            case Tfloat80:
                warning(loc, "min property is deprecated, use min_normal instead");
                goto Lmin_normal;
        }
    }
    else if (ident == Id::min_normal)
    {
      Lmin_normal:
        switch (ty)
        {
            case Tcomplex32:
            case Timaginary32:
            case Tfloat32:      fvalue = FLT_MIN;       goto Lfvalue;
            case Tcomplex64:
            case Timaginary64:
            case Tfloat64:      fvalue = DBL_MIN;       goto Lfvalue;
            case Tcomplex80:
            case Timaginary80:
            case Tfloat80:      fvalue = LDBL_MIN;      goto Lfvalue;
        }
    }
    else if (ident == Id::nan)
    {
        switch (ty)
        {
            case Tcomplex32:
            case Tcomplex64:
            case Tcomplex80:
            case Timaginary32:
            case Timaginary64:
            case Timaginary80:
            case Tfloat32:
            case Tfloat64:
            case Tfloat80:
            {
                fvalue = Port::nan;
                goto Lfvalue;
            }
        }
    }
    else if (ident == Id::infinity)
    {
        switch (ty)
        {
            case Tcomplex32:
            case Tcomplex64:
            case Tcomplex80:
            case Timaginary32:
            case Timaginary64:
            case Timaginary80:
            case Tfloat32:
            case Tfloat64:
            case Tfloat80:
                fvalue = Port::infinity;
                goto Lfvalue;
        }
    }
    else if (ident == Id::dig)
    {
        switch (ty)
        {
            case Tcomplex32:
            case Timaginary32:
            case Tfloat32:      ivalue = FLT_DIG;       goto Lint;
            case Tcomplex64:
            case Timaginary64:
            case Tfloat64:      ivalue = DBL_DIG;       goto Lint;
            case Tcomplex80:
            case Timaginary80:
            case Tfloat80:      ivalue = LDBL_DIG;      goto Lint;
        }
    }
    else if (ident == Id::epsilon)
    {
        switch (ty)
        {
            case Tcomplex32:
            case Timaginary32:
            case Tfloat32:      fvalue = FLT_EPSILON;   goto Lfvalue;
            case Tcomplex64:
            case Timaginary64:
            case Tfloat64:      fvalue = DBL_EPSILON;   goto Lfvalue;
            case Tcomplex80:
            case Timaginary80:
            case Tfloat80:      fvalue = LDBL_EPSILON;  goto Lfvalue;
        }
    }
    else if (ident == Id::mant_dig)
    {
        switch (ty)
        {
            case Tcomplex32:
            case Timaginary32:
            case Tfloat32:      ivalue = FLT_MANT_DIG;  goto Lint;
            case Tcomplex64:
            case Timaginary64:
            case Tfloat64:      ivalue = DBL_MANT_DIG;  goto Lint;
            case Tcomplex80:
            case Timaginary80:
            case Tfloat80:      ivalue = LDBL_MANT_DIG; goto Lint;
        }
    }
    else if (ident == Id::max_10_exp)
    {
        switch (ty)
        {
            case Tcomplex32:
            case Timaginary32:
            case Tfloat32:      ivalue = FLT_MAX_10_EXP;        goto Lint;
            case Tcomplex64:
            case Timaginary64:
            case Tfloat64:      ivalue = DBL_MAX_10_EXP;        goto Lint;
            case Tcomplex80:
            case Timaginary80:
            case Tfloat80:      ivalue = LDBL_MAX_10_EXP;       goto Lint;
        }
    }
    else if (ident == Id::max_exp)
    {
        switch (ty)
        {
            case Tcomplex32:
            case Timaginary32:
            case Tfloat32:      ivalue = FLT_MAX_EXP;   goto Lint;
            case Tcomplex64:
            case Timaginary64:
            case Tfloat64:      ivalue = DBL_MAX_EXP;   goto Lint;
            case Tcomplex80:
            case Timaginary80:
            case Tfloat80:      ivalue = LDBL_MAX_EXP;  goto Lint;
        }
    }
    else if (ident == Id::min_10_exp)
    {
        switch (ty)
        {
            case Tcomplex32:
            case Timaginary32:
            case Tfloat32:      ivalue = FLT_MIN_10_EXP;        goto Lint;
            case Tcomplex64:
            case Timaginary64:
            case Tfloat64:      ivalue = DBL_MIN_10_EXP;        goto Lint;
            case Tcomplex80:
            case Timaginary80:
            case Tfloat80:      ivalue = LDBL_MIN_10_EXP;       goto Lint;
        }
    }
    else if (ident == Id::min_exp)
    {
        switch (ty)
        {
            case Tcomplex32:
            case Timaginary32:
            case Tfloat32:      ivalue = FLT_MIN_EXP;   goto Lint;
            case Tcomplex64:
            case Timaginary64:
            case Tfloat64:      ivalue = DBL_MIN_EXP;   goto Lint;
            case Tcomplex80:
            case Timaginary80:
            case Tfloat80:      ivalue = LDBL_MIN_EXP;  goto Lint;
        }
    }

    return Type::getProperty(loc, ident, flag);

Livalue:
    e = new IntegerExp(loc, ivalue, this);
    return e;

Lfvalue:
    if (isreal() || isimaginary())
        e = new RealExp(loc, fvalue, this);
    else
    {
        complex_t cvalue;

#if __DMC__
        //((real_t *)&cvalue)[0] = fvalue;
        //((real_t *)&cvalue)[1] = fvalue;
        cvalue = fvalue + fvalue * I;
#else
        cvalue.re = fvalue;
        cvalue.im = fvalue;
#endif
        //for (int i = 0; i < 20; i++)
        //    printf("%02x ", ((unsigned char *)&cvalue)[i]);
        //printf("\n");
        e = new ComplexExp(loc, cvalue, this);
    }
    return e;

Lint:
    e = new IntegerExp(loc, ivalue, Type::tint32);
    return e;
}

Expression *TypeBasic::dotExp(Scope *sc, Expression *e, Identifier *ident, int flag)
{
#if LOGDOTEXP
    printf("TypeBasic::dotExp(e = '%s', ident = '%s')\n", e->toChars(), ident->toChars());
#endif
    Type *t;

    if (ident == Id::re)
    {
        switch (ty)
        {
            case Tcomplex32:    t = tfloat32;           goto L1;
            case Tcomplex64:    t = tfloat64;           goto L1;
            case Tcomplex80:    t = tfloat80;           goto L1;
            L1:
                e = e->castTo(sc, t);
                break;

            case Tfloat32:
            case Tfloat64:
            case Tfloat80:
                break;

            case Timaginary32:  t = tfloat32;           goto L2;
            case Timaginary64:  t = tfloat64;           goto L2;
            case Timaginary80:  t = tfloat80;           goto L2;
            L2:
                e = new RealExp(e->loc, ldouble(0.0), t);
                break;

            default:
                e = Type::getProperty(e->loc, ident, flag);
                break;
        }
    }
    else if (ident == Id::im)
    {   Type *t2;

        switch (ty)
        {
            case Tcomplex32:    t = timaginary32;       t2 = tfloat32;  goto L3;
            case Tcomplex64:    t = timaginary64;       t2 = tfloat64;  goto L3;
            case Tcomplex80:    t = timaginary80;       t2 = tfloat80;  goto L3;
            L3:
                e = e->castTo(sc, t);
                e->type = t2;
                break;

            case Timaginary32:  t = tfloat32;   goto L4;
            case Timaginary64:  t = tfloat64;   goto L4;
            case Timaginary80:  t = tfloat80;   goto L4;
            L4:
                e = e->copy();
                e->type = t;
                break;

            case Tfloat32:
            case Tfloat64:
            case Tfloat80:
                e = new RealExp(e->loc, ldouble(0.0), this);
                break;

            default:
                e = Type::getProperty(e->loc, ident, flag);
                break;
        }
    }
    else
    {
        return Type::dotExp(sc, e, ident, flag);
    }
    if (!flag || e)
        e = e->semantic(sc);
    return e;
}

Expression *TypeBasic::defaultInit(Loc loc)
{   dinteger_t value = 0;

#if SNAN_DEFAULT_INIT
    /*
     * Use a payload which is different from the machine NaN,
     * so that uninitialised variables can be
     * detected even if exceptions are disabled.
     */
    union
    {   unsigned short us[8];
        longdouble     ld;
    } snan = {{ 0, 0, 0, 0xA000, 0x7FFF }};
    /*
     * Although long doubles are 10 bytes long, some
     * C ABIs pad them out to 12 or even 16 bytes, so
     * leave enough space in the snan array.
     */
    assert(Target::realsize <= sizeof(snan));
    d_float80 fvalue = snan.ld;
#endif

#if LOGDEFAULTINIT
    printf("TypeBasic::defaultInit() '%s'\n", toChars());
#endif
    switch (ty)
    {
        case Tchar:
            value = 0xFF;
            break;

        case Twchar:
        case Tdchar:
            value = 0xFFFF;
            break;

        case Timaginary32:
        case Timaginary64:
        case Timaginary80:
        case Tfloat32:
        case Tfloat64:
        case Tfloat80:
#if SNAN_DEFAULT_INIT
            return new RealExp(loc, fvalue, this);
#else
            return getProperty(loc, Id::nan);
#endif

        case Tcomplex32:
        case Tcomplex64:
        case Tcomplex80:
#if SNAN_DEFAULT_INIT
        {   // Can't use fvalue + I*fvalue (the im part becomes a quiet NaN).
            complex_t cvalue;
            ((real_t *)&cvalue)[0] = fvalue;
            ((real_t *)&cvalue)[1] = fvalue;
            return new ComplexExp(loc, cvalue, this);
        }
#else
            return getProperty(loc, Id::nan);
#endif

        case Tvoid:
            error(loc, "void does not have a default initializer");
            return new ErrorExp();
    }
    return new IntegerExp(loc, value, this);
}

int TypeBasic::isZeroInit(Loc loc)
{
    switch (ty)
    {
        case Tchar:
        case Twchar:
        case Tdchar:
        case Timaginary32:
        case Timaginary64:
        case Timaginary80:
        case Tfloat32:
        case Tfloat64:
        case Tfloat80:
        case Tcomplex32:
        case Tcomplex64:
        case Tcomplex80:
            return 0;           // no
        default:
            return 1;           // yes
    }
}

int TypeBasic::isintegral()
{
    //printf("TypeBasic::isintegral('%s') x%x\n", toChars(), flags);
    return flags & TFLAGSintegral;
}

int TypeBasic::isfloating()
{
    return flags & TFLAGSfloating;
}

int TypeBasic::isreal()
{
    return flags & TFLAGSreal;
}

int TypeBasic::isimaginary()
{
    return flags & TFLAGSimaginary;
}

int TypeBasic::iscomplex()
{
    return flags & TFLAGScomplex;
}

int TypeBasic::isunsigned()
{
    return flags & TFLAGSunsigned;
}

int TypeBasic::isscalar()
{
    return flags & (TFLAGSintegral | TFLAGSfloating);
}

MATCH TypeBasic::implicitConvTo(Type *to)
{
    //printf("TypeBasic::implicitConvTo(%s) from %s\n", to->toChars(), toChars());
    if (this == to)
        return MATCHexact;

#if DMDV2
    if (ty == to->ty)
    {
        if (mod == to->mod)
            return MATCHexact;
        else if (MODimplicitConv(mod, to->mod))
            return MATCHconst;
        else if (!((mod ^ to->mod) & MODshared))    // for wild matching
            return MATCHconst;
        else
            return MATCHconvert;
    }
#endif

    if (ty == Tvoid || to->ty == Tvoid)
        return MATCHnomatch;
    if (to->ty == Tbool)
        return MATCHnomatch;

    TypeBasic *tob;
    if (to->ty == Tvector && to->deco)
    {
        TypeVector *tv = (TypeVector *)to;
        tob = tv->elementType();
    }
    else
        tob = to->isTypeBasic();
    if (!tob)
        return MATCHnomatch;

    if (flags & TFLAGSintegral)
    {
        // Disallow implicit conversion of integers to imaginary or complex
        if (tob->flags & (TFLAGSimaginary | TFLAGScomplex))
            return MATCHnomatch;

#if DMDV2
        // If converting from integral to integral
        if (tob->flags & TFLAGSintegral)
        {   d_uns64 sz = size(Loc());
            d_uns64 tosz = tob->size(Loc());

            /* Can't convert to smaller size
             */
            if (sz > tosz)
                return MATCHnomatch;

            /* Can't change sign if same size
             */
            /*if (sz == tosz && (flags ^ tob->flags) & TFLAGSunsigned)
                return MATCHnomatch;*/
        }
#endif
    }
    else if (flags & TFLAGSfloating)
    {
        // Disallow implicit conversion of floating point to integer
        if (tob->flags & TFLAGSintegral)
            return MATCHnomatch;

        assert(tob->flags & TFLAGSfloating || to->ty == Tvector);

        // Disallow implicit conversion from complex to non-complex
        if (flags & TFLAGScomplex && !(tob->flags & TFLAGScomplex))
            return MATCHnomatch;

        // Disallow implicit conversion of real or imaginary to complex
        if (flags & (TFLAGSreal | TFLAGSimaginary) &&
            tob->flags & TFLAGScomplex)
            return MATCHnomatch;

        // Disallow implicit conversion to-from real and imaginary
        if ((flags & (TFLAGSreal | TFLAGSimaginary)) !=
            (tob->flags & (TFLAGSreal | TFLAGSimaginary)))
            return MATCHnomatch;
    }
    return MATCHconvert;
}

TypeBasic *TypeBasic::isTypeBasic()
{
    return (TypeBasic *)this;
}

/* ============================= TypeVector =========================== */

/* The basetype must be one of:
 *   byte[16],ubyte[16],short[8],ushort[8],int[4],uint[4],long[2],ulong[2],float[4],double[2]
 * For AVX:
 *   byte[32],ubyte[32],short[16],ushort[16],int[8],uint[8],long[4],ulong[4],float[8],double[4]
 */
TypeVector::TypeVector(Loc loc, Type *basetype)
        : Type(Tvector)
{
    this->basetype = basetype;
}

const char *TypeVector::kind()
{
    return "vector";
}

Type *TypeVector::syntaxCopy()
{
    return new TypeVector(Loc(), basetype->syntaxCopy());
}

Type *TypeVector::semantic(Loc loc, Scope *sc)
{
    int errors = global.errors;
    basetype = basetype->semantic(loc, sc);
    if (errors != global.errors)
        return terror;
    basetype = basetype->toBasetype()->mutableOf();
    if (basetype->ty != Tsarray)
    {   error(loc, "T in __vector(T) must be a static array, not %s", basetype->toChars());
        return terror;
    }
    TypeSArray *t = (TypeSArray *)basetype;
    d_uns64 sz = t->size(loc);
    if (sz != 16 && sz != 32)
    {   error(loc, "base type of __vector must be a 16 or 32 byte static array, not %s", t->toChars());
        return terror;
    }
    TypeBasic *tb = t->nextOf()->isTypeBasic();
    if (!tb || !(tb->flags & TFLAGSvector))
    {   error(loc, "base type of __vector must be a static array of an arithmetic type, not %s", t->toChars());
        return terror;
    }
    return merge();
}

TypeBasic *TypeVector::elementType()
{
    assert(basetype->ty == Tsarray);
    TypeSArray *t = (TypeSArray *)basetype;
    TypeBasic *tb = t->nextOf()->isTypeBasic();
    assert(tb);
    return tb;
}

int TypeVector::checkBoolean()
{
    return FALSE;
}

char *TypeVector::toChars()
{
    return Type::toChars();
}

void TypeVector::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    //printf("TypeVector::toCBuffer2(mod = %d, this->mod = %d)\n", mod, this->mod);
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    buf->writestring("__vector(");
    basetype->toCBuffer2(buf, hgs, this->mod);
    buf->writestring(")");
}

void TypeVector::toDecoBuffer(OutBuffer *buf, int flag)
{
    if (flag != mod && flag != 0x100)
    {
        MODtoDecoBuffer(buf, mod);
    }
    buf->writestring("Nh");
    basetype->toDecoBuffer(buf, (flag & 0x100) ? 0 : mod);
}

d_uns64 TypeVector::size(Loc loc)
{
    return basetype->size();
}

unsigned TypeVector::alignsize()
{
    return (unsigned)basetype->size();
}

Expression *TypeVector::getProperty(Loc loc, Identifier *ident, int flag)
{
    return basetype->getProperty(loc, ident, flag);
}

Expression *TypeVector::dotExp(Scope *sc, Expression *e, Identifier *ident, int flag)
{
#if LOGDOTEXP
    printf("TypeVector::dotExp(e = '%s', ident = '%s')\n", e->toChars(), ident->toChars());
#endif
    if (ident == Id::array)
    {
        e = e->castTo(sc, basetype);
        return e;
    }
    return basetype->dotExp(sc, e->castTo(sc, basetype), ident, flag);
}

Expression *TypeVector::defaultInit(Loc loc)
{
    return basetype->defaultInit(loc);
}

int TypeVector::isZeroInit(Loc loc)
{
    return basetype->isZeroInit(loc);
}

int TypeVector::isintegral()
{
    //printf("TypeVector::isintegral('%s') x%x\n", toChars(), flags);
    return basetype->nextOf()->isintegral();
}

int TypeVector::isfloating()
{
    return basetype->nextOf()->isfloating();
}

int TypeVector::isunsigned()
{
    return basetype->nextOf()->isunsigned();
}

int TypeVector::isscalar()
{
    return basetype->nextOf()->isscalar();
}

MATCH TypeVector::implicitConvTo(Type *to)
{
    //printf("TypeVector::implicitConvTo(%s) from %s\n", to->toChars(), toChars());
    if (this == to)
        return MATCHexact;
    if (ty == to->ty)
        return MATCHconvert;
    return MATCHnomatch;
}

Type *TypeVector::reliesOnTident(TemplateParameters *tparams)
{
    return basetype->reliesOnTident(tparams);
}

/***************************** TypeArray *****************************/

TypeArray::TypeArray(TY ty, Type *next)
    : TypeNext(ty, next)
{
}

Expression *TypeArray::dotExp(Scope *sc, Expression *e, Identifier *ident, int flag)
{
    Type *n = this->next->toBasetype();         // uncover any typedef's

#if LOGDOTEXP
    printf("TypeArray::dotExp(e = '%s', ident = '%s')\n", e->toChars(), ident->toChars());
#endif

    if (!n->isMutable())
        if (ident == Id::sort || ident == Id::reverse)
        {   error(e->loc, "can only %s a mutable array", ident->toChars());
            goto Lerror;
        }

    if (ident == Id::reverse && (n->ty == Tchar || n->ty == Twchar))
    {
        static const char *name[2] = { "_adReverseChar", "_adReverseWchar" };

        const char *nm = name[n->ty == Twchar];
        FuncDeclaration *fd = FuncDeclaration::genCfunc(n->arrayOf(), nm);
        Expression *ec = new VarExp(Loc(), fd);
        e = e->castTo(sc, n->arrayOf());        // convert to dynamic array
        Expressions *arguments = new Expressions();
        arguments->push(e);
        e = new CallExp(e->loc, ec, arguments);
        e->type = next->arrayOf();
    }
    else if (ident == Id::sort && (n->ty == Tchar || n->ty == Twchar))
    {
        const char *nm = n->ty == Twchar ? "_adSortWchar" : "_adSortChar";
        FuncDeclaration *fd = FuncDeclaration::genCfunc(n->arrayOf(), nm);
        Expression *ec = new VarExp(Loc(), fd);
        e = e->castTo(sc, n->arrayOf());        // convert to dynamic array
        Expressions *arguments = new Expressions();
        arguments->push(e);
        e = new CallExp(e->loc, ec, arguments);
        e->type = next->arrayOf();
    }
    else if (ident == Id::reverse || ident == Id::dup || ident == Id::idup)
    {
        Expression *ec;
        FuncDeclaration *fd;
        Expressions *arguments;
        int size = next->size(e->loc);
        int dup;

        Expression *olde = e;
        assert(size);
        dup = (ident == Id::dup || ident == Id::idup);
        fd = FuncDeclaration::genCfunc(tvoid->arrayOf(), dup ? Id::adDup : Id::adReverse);
        ec = new VarExp(Loc(), fd);
        e = e->castTo(sc, n->arrayOf());        // convert to dynamic array
        arguments = new Expressions();
        if (dup)
            arguments->push(getTypeInfo(sc));
        arguments->push(e);
        if (!dup)
            arguments->push(new IntegerExp(Loc(), size, Type::tsize_t));
        e = new CallExp(e->loc, ec, arguments);
        if (ident == Id::idup)
        {   Type *einv = next->immutableOf();
            if (next->implicitConvTo(einv) < MATCHconst)
            {   error(e->loc, "cannot implicitly convert element type %s to immutable in %s.idup",
                    next->toChars(), olde->toChars());
                goto Lerror;
            }
            e->type = einv->arrayOf();
        }
        else if (ident == Id::dup)
        {
            Type *emut = next->mutableOf();
            if (next->implicitConvTo(emut) < MATCHconst)
            {   error(e->loc, "cannot implicitly convert element type %s to mutable in %s.dup",
                    next->toChars(), olde->toChars());
                goto Lerror;
            }
            e->type = emut->arrayOf();
        }
        else
            e->type = next->mutableOf()->arrayOf();
    }
    else if (ident == Id::sort)
    {
        Expression *ec;
        FuncDeclaration *fd;
        Expressions *arguments;

        fd = FuncDeclaration::genCfunc(tvoid->arrayOf(), "_adSort");
        ec = new VarExp(Loc(), fd);
        e = e->castTo(sc, n->arrayOf());        // convert to dynamic array
        arguments = new Expressions();
        arguments->push(e);
        arguments->push(n->ty == Tsarray
                    ? n->getTypeInfo(sc)        // don't convert to dynamic array
                    : n->getInternalTypeInfo(sc));
        e = new CallExp(e->loc, ec, arguments);
        e->type = next->arrayOf();
    }
    else
    {
        e = Type::dotExp(sc, e, ident, flag);
    }
    if (!flag || e)
        e = e->semantic(sc);
    return e;

Lerror:
    return new ErrorExp();
}


/***************************** TypeSArray *****************************/

TypeSArray::TypeSArray(Type *t, Expression *dim)
    : TypeArray(Tsarray, t)
{
    //printf("TypeSArray(%s)\n", dim->toChars());
    this->dim = dim;
}

const char *TypeSArray::kind()
{
    return "sarray";
}

Type *TypeSArray::syntaxCopy()
{
    Type *t = next->syntaxCopy();
    Expression *e = dim->syntaxCopy();
    t = new TypeSArray(t, e);
    t->mod = mod;
    return t;
}

d_uns64 TypeSArray::size(Loc loc)
{   dinteger_t sz;

    if (!dim)
        return Type::size(loc);
    sz = dim->toInteger();

    {   dinteger_t n, n2;

        n = next->size();
        n2 = n * sz;
        if (n && (n2 / n) != sz)
            goto Loverflow;
        sz = n2;
    }
    return sz;

Loverflow:
    error(loc, "index %lld overflow for static array", (long long)sz);
    return SIZE_INVALID;
}

unsigned TypeSArray::alignsize()
{
    return next->alignsize();
}

/**************************
 * This evaluates exp while setting length to be the number
 * of elements in the tuple t.
 */
Expression *semanticLength(Scope *sc, Type *t, Expression *exp)
{
    if (t->ty == Ttuple)
    {   ScopeDsymbol *sym = new ArrayScopeSymbol(sc, (TypeTuple *)t);
        sym->parent = sc->scopesym;
        sc = sc->push(sym);

        exp = exp->ctfeSemantic(sc);

        sc->pop();
    }
    else
        exp = exp->ctfeSemantic(sc);
    return exp;
}

Expression *semanticLength(Scope *sc, TupleDeclaration *s, Expression *exp)
{
    ScopeDsymbol *sym = new ArrayScopeSymbol(sc, s);
    sym->parent = sc->scopesym;
    sc = sc->push(sym);

    exp = exp->ctfeSemantic(sc);

    sc->pop();
    return exp;
}

void TypeSArray::resolve(Loc loc, Scope *sc, Expression **pe, Type **pt, Dsymbol **ps)
{
    //printf("TypeSArray::resolve() %s\n", toChars());
    next->resolve(loc, sc, pe, pt, ps);
    //printf("s = %p, e = %p, t = %p\n", *ps, *pe, *pt);
    if (*pe)
    {   // It's really an index expression
        Expressions *exps = new Expressions();
        exps->setDim(1);
        (*exps)[0] = dim;
        if (Dsymbol *s = getDsymbol(*pe))
            *pe = new DsymbolExp(loc, s, 1);
        *pe = new ArrayExp(loc, *pe, exps);
    }
    else if (*ps)
    {   Dsymbol *s = *ps;
        TupleDeclaration *td = s->isTupleDeclaration();
        if (td)
        {
            ScopeDsymbol *sym = new ArrayScopeSymbol(sc, td);
            sym->parent = sc->scopesym;
            sc = sc->push(sym);

            dim = dim->ctfeSemantic(sc);
            dim = dim->ctfeInterpret();
            uinteger_t d = dim->toUInteger();

            sc = sc->pop();

            if (d >= td->objects->dim)
            {   error(loc, "tuple index %llu exceeds length %u", d, td->objects->dim);
                goto Ldefault;
            }
            RootObject *o = (*td->objects)[(size_t)d];
            if (o->dyncast() == DYNCAST_DSYMBOL)
            {
                *ps = (Dsymbol *)o;
                return;
            }
            if (o->dyncast() == DYNCAST_EXPRESSION)
            {
                Expression *e = (Expression *)o;
                if (e->op == TOKdsymbol)
                {
                    *ps = ((DsymbolExp *)e)->s;
                    *pe = NULL;
                }
                else
                {
                    *ps = NULL;
                    *pe = e;
                }
                return;
            }
            if (o->dyncast() == DYNCAST_TYPE)
            {
                *ps = NULL;
                *pt = ((Type *)o)->addMod(this->mod);
                return;
            }

            /* Create a new TupleDeclaration which
             * is a slice [d..d+1] out of the old one.
             * Do it this way because TemplateInstance::semanticTiargs()
             * can handle unresolved Objects this way.
             */
            Objects *objects = new Objects;
            objects->setDim(1);
            (*objects)[0] = o;

            TupleDeclaration *tds = new TupleDeclaration(loc, td->ident, objects);
            *ps = tds;
        }
        else
            goto Ldefault;
    }
    else
    {
     Ldefault:
        Type::resolve(loc, sc, pe, pt, ps);
    }
}

Type *TypeSArray::semantic(Loc loc, Scope *sc)
{
    //printf("TypeSArray::semantic() %s\n", toChars());

    Type *t;
    Expression *e;
    Dsymbol *s;
    next->resolve(loc, sc, &e, &t, &s);
    if (dim && s && s->isTupleDeclaration())
    {   TupleDeclaration *sd = s->isTupleDeclaration();

        dim = semanticLength(sc, sd, dim);
        dim = dim->ctfeInterpret();
        uinteger_t d = dim->toUInteger();

        if (d >= sd->objects->dim)
        {   error(loc, "tuple index %llu exceeds %u", d, sd->objects->dim);
            return Type::terror;
        }
        RootObject *o = (*sd->objects)[(size_t)d];
        if (o->dyncast() != DYNCAST_TYPE)
        {   error(loc, "%s is not a type", toChars());
            return Type::terror;
        }
        t = ((Type *)o)->addMod(this->mod);
        return t;
    }

    Type *tn = next->semantic(loc,sc);
    if (tn->ty == Terror)
        return terror;

    Type *tbn = tn->toBasetype();

    if (dim)
    {   dinteger_t n, n2;

        int errors = global.errors;
        dim = semanticLength(sc, tbn, dim);
        if (errors != global.errors)
            goto Lerror;

        dim = dim->optimize(WANTvalue);
        dim = dim->ctfeInterpret();
        errors = global.errors;
        dinteger_t d1 = dim->toInteger();
        if (errors != global.errors)
            goto Lerror;
        dim = dim->implicitCastTo(sc, tsize_t);
        dim = dim->optimize(WANTvalue);
        errors = global.errors;
        dinteger_t d2 = dim->toInteger();
        if (errors != global.errors)
            goto Lerror;

        if (dim->op == TOKerror)
            goto Lerror;

        if (d1 != d2)
            goto Loverflow;

        if (tbn->isintegral() ||
                 tbn->isfloating() ||
                 tbn->ty == Tpointer ||
                 tbn->ty == Tarray ||
                 tbn->ty == Tsarray ||
                 tbn->ty == Taarray ||
                 tbn->ty == Tclass)
        {
            /* Only do this for types that don't need to have semantic()
             * run on them for the size, since they may be forward referenced.
             */
            n = tbn->size(loc);
            n2 = n * d2;
            if ((int)n2 < 0)
                goto Loverflow;
            if (n2 >= 0x1000000)        // put a 'reasonable' limit on it
                goto Loverflow;
            if (n && n2 / n != d2)
            {
              Loverflow:
                error(loc, "index %lld overflow for static array", d1);
                goto Lerror;
            }
        }
    }
    switch (tbn->ty)
    {
        case Ttuple:
        {   // Index the tuple to get the type
            assert(dim);
            TypeTuple *tt = (TypeTuple *)tbn;
            uinteger_t d = dim->toUInteger();

            if (d >= tt->arguments->dim)
            {   error(loc, "tuple index %llu exceeds %u", d, tt->arguments->dim);
                goto Lerror;
            }
            Parameter *arg = (*tt->arguments)[(size_t)d];
            return arg->type->addMod(this->mod);
        }
        case Tfunction:
        case Tnone:
            error(loc, "can't have array of %s", tbn->toChars());
            goto Lerror;
        default:
            break;
    }
    if (tbn->isscope())
    {   error(loc, "cannot have array of scope %s", tbn->toChars());
        goto Lerror;
    }

    /* Ensure things like const(immutable(T)[3]) become immutable(T[3])
     * and const(T)[3] become const(T[3])
     */
    next = tn;
    transitive();
    t = addMod(tn->mod);

    return t->merge();

Lerror:
    return Type::terror;
}

void TypeSArray::toDecoBuffer(OutBuffer *buf, int flag)
{
    Type::toDecoBuffer(buf, flag);
    if (dim)
        buf->printf("%llu", dim->toInteger());
    if (next)
        /* Note that static arrays are value types, so
         * for a parameter, propagate the 0x100 to the next
         * level, since for T[4][3], any const should apply to the T,
         * not the [4].
         */
        next->toDecoBuffer(buf,  (flag & 0x100) ? flag : mod);
}

void TypeSArray::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    next->toCBuffer2(buf, hgs, this->mod);
    buf->printf("[%s]", dim->toChars());
}

Expression *TypeSArray::dotExp(Scope *sc, Expression *e, Identifier *ident, int flag)
{
#if LOGDOTEXP
    printf("TypeSArray::dotExp(e = '%s', ident = '%s')\n", e->toChars(), ident->toChars());
#endif
    if (ident == Id::length)
    {
        Loc oldLoc = e->loc;
        e = dim->copy();
        e->loc = oldLoc;
    }
    else if (ident == Id::ptr)
    {
        if (size(e->loc) == 0)
            e = new NullExp(e->loc, next->pointerTo());
        else
        {
            e = new IndexExp(e->loc, e, new IntegerExp(0));
            e = new AddrExp(e->loc, e);
        }
    }
    else
    {
        e = TypeArray::dotExp(sc, e, ident, flag);
    }
    if (!flag && e)
        e = e->semantic(sc);
    return e;
}

structalign_t TypeSArray::alignment()
{
    return next->alignment();
}

int TypeSArray::isString()
{
    TY nty = next->toBasetype()->ty;
    return nty == Tchar || nty == Twchar || nty == Tdchar;
}

MATCH TypeSArray::constConv(Type *to)
{
    if (to->ty == Tsarray)
    {
        TypeSArray *tsa = (TypeSArray *)to;
        if (!dim->equals(tsa->dim))
            return MATCHnomatch;
    }
    return TypeNext::constConv(to);
}

MATCH TypeSArray::implicitConvTo(Type *to)
{
    //printf("TypeSArray::implicitConvTo(to = %s) this = %s\n", to->toChars(), toChars());

    // Allow implicit conversion of static array to pointer or dynamic array
    if (IMPLICIT_ARRAY_TO_PTR && to->ty == Tpointer)
    {
        TypePointer *tp = (TypePointer *)to;

        if (!MODimplicitConv(next->mod, tp->next->mod))
            return MATCHnomatch;

        if (tp->next->ty == Tvoid || next->constConv(tp->next) != MATCHnomatch)
        {
            return MATCHconvert;
        }
        return MATCHnomatch;
    }
    if (to->ty == Tarray)
    {
        TypeDArray *ta = (TypeDArray *)to;

        if (!MODimplicitConv(next->mod, ta->next->mod))
            return MATCHnomatch;

        /* Allow conversion to void[]
         */
        if (ta->next->ty == Tvoid)
        {
            return MATCHconvert;
        }

        MATCH m = next->constConv(ta->next);
        if (m != MATCHnomatch)
        {
            return MATCHconvert;
        }
        return MATCHnomatch;
    }

    if (to->ty == Tsarray)
    {
        if (this == to)
            return MATCHexact;

        TypeSArray *tsa = (TypeSArray *)to;

        if (dim->equals(tsa->dim))
        {
            /* Since static arrays are value types, allow
             * conversions from const elements to non-const
             * ones, just like we allow conversion from const int
             * to int.
             */
            MATCH m = next->implicitConvTo(tsa->next);
            if (m >= MATCHconst)
            {
                if (mod != to->mod)
                    m = MATCHconst;
                return m;
            }
        }
    }
    return MATCHnomatch;
}

Expression *TypeSArray::defaultInit(Loc loc)
{
#if LOGDEFAULTINIT
    printf("TypeSArray::defaultInit() '%s'\n", toChars());
#endif
    return next->defaultInit(loc);
}

int TypeSArray::isZeroInit(Loc loc)
{
    return next->isZeroInit(loc);
}

int TypeSArray::needsDestruction()
{
    return next->needsDestruction();
}

/*********************************
 *
 */

bool TypeSArray::needsNested()
{
    return next->needsNested();
}

Expression *TypeSArray::defaultInitLiteral(Loc loc)
{
#if LOGDEFAULTINIT
    printf("TypeSArray::defaultInitLiteral() '%s'\n", toChars());
#endif
    size_t d = dim->toInteger();
    Expression *elementinit;
    if (next->ty == Tvoid)
        elementinit = tuns8->defaultInitLiteral(loc);
    else
        elementinit = next->defaultInitLiteral(loc);
    Expressions *elements = new Expressions();
    elements->setDim(d);
    for (size_t i = 0; i < d; i++)
        (*elements)[i] = elementinit;
    ArrayLiteralExp *ae = new ArrayLiteralExp(Loc(), elements);
    ae->type = this;
    return ae;
}

Expression *TypeSArray::toExpression()
{
    Expression *e = next->toExpression();
    if (e)
    {   Expressions *arguments = new Expressions();
        arguments->push(dim);
        e = new ArrayExp(dim->loc, e, arguments);
    }
    return e;
}

int TypeSArray::hasPointers()
{
    /* Don't want to do this, because:
     *    struct S { T* array[0]; }
     * may be a variable length struct.
     */
    //if (dim->toInteger() == 0)
        //return FALSE;

    if (next->ty == Tvoid)
        // Arrays of void contain arbitrary data, which may include pointers
        return TRUE;
    else
        return next->hasPointers();
}

/***************************** TypeDArray *****************************/

TypeDArray::TypeDArray(Type *t)
    : TypeArray(Tarray, t)
{
    //printf("TypeDArray(t = %p)\n", t);
}

const char *TypeDArray::kind()
{
    return "darray";
}

Type *TypeDArray::syntaxCopy()
{
    Type *t = next->syntaxCopy();
    if (t == next)
        t = this;
    else
    {   t = new TypeDArray(t);
        t->mod = mod;
    }
    return t;
}

d_uns64 TypeDArray::size(Loc loc)
{
    //printf("TypeDArray::size()\n");
    return Target::ptrsize * 2;
}

unsigned TypeDArray::alignsize()
{
    // A DArray consists of two ptr-sized values, so align it on pointer size
    // boundary
    return Target::ptrsize;
}

Type *TypeDArray::semantic(Loc loc, Scope *sc)
{
    Type *tn = next->semantic(loc,sc);
    Type *tbn = tn->toBasetype();
    switch (tbn->ty)
    {
        case Tfunction:
        case Tnone:
        case Ttuple:
            error(loc, "can't have array of %s", tbn->toChars());
        case Terror:
            return Type::terror;
        default:
            break;
    }
    if (tn->isscope())
    {   error(loc, "cannot have array of scope %s", tn->toChars());
        return Type::terror;
    }
    next = tn;
    transitive();
    return merge();
}

void TypeDArray::resolve(Loc loc, Scope *sc, Expression **pe, Type **pt, Dsymbol **ps)
{
    //printf("TypeDArray::resolve() %s\n", toChars());
    next->resolve(loc, sc, pe, pt, ps);
    //printf("s = %p, e = %p, t = %p\n", *ps, *pe, *pt);
    if (*pe)
    {   // It's really a slice expression
        if (Dsymbol *s = getDsymbol(*pe))
            *pe = new DsymbolExp(loc, s, 1);
        *pe = new SliceExp(loc, *pe, NULL, NULL);
    }
    else if (*ps)
    {
        TupleDeclaration *td = (*ps)->isTupleDeclaration();
        if (td)
            ;   // keep *ps
        else
            goto Ldefault;
    }
    else
    {
     Ldefault:
        Type::resolve(loc, sc, pe, pt, ps);
    }
}

void TypeDArray::toDecoBuffer(OutBuffer *buf, int flag)
{
    Type::toDecoBuffer(buf, flag);
    if (next)
        next->toDecoBuffer(buf, (flag & 0x100) ? 0 : mod);
}

void TypeDArray::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    if (equals(tstring))
        buf->writestring("string");
    else
    {   next->toCBuffer2(buf, hgs, this->mod);
        buf->writestring("[]");
    }
}

Expression *TypeDArray::dotExp(Scope *sc, Expression *e, Identifier *ident, int flag)
{
#if LOGDOTEXP
    printf("TypeDArray::dotExp(e = '%s', ident = '%s')\n", e->toChars(), ident->toChars());
#endif
    if (ident == Id::length)
    {
        if (e->op == TOKstring)
        {   StringExp *se = (StringExp *)e;

            return new IntegerExp(se->loc, se->len, Type::tindex);
        }
        if (e->op == TOKnull)
            return new IntegerExp(e->loc, 0, Type::tindex);
        e = new ArrayLengthExp(e->loc, e);
        e->type = Type::tsize_t;
        return e;
    }
    else if (ident == Id::ptr)
    {
        e = e->castTo(sc, next->pointerTo());
        return e;
    }
    else
    {
        e = TypeArray::dotExp(sc, e, ident, flag);
    }
    return e;
}

int TypeDArray::isString()
{
    TY nty = next->toBasetype()->ty;
    return nty == Tchar || nty == Twchar || nty == Tdchar;
}

MATCH TypeDArray::implicitConvTo(Type *to)
{
    //printf("TypeDArray::implicitConvTo(to = %s) this = %s\n", to->toChars(), toChars());
    if (equals(to))
        return MATCHexact;

    // Allow implicit conversion of array to pointer
    if (IMPLICIT_ARRAY_TO_PTR && to->ty == Tpointer)
    {
        TypePointer *tp = (TypePointer *)to;

        /* Allow conversion to void*
         */
        if (tp->next->ty == Tvoid &&
            MODimplicitConv(next->mod, tp->next->mod))
        {
            return MATCHconvert;
        }

        return next->constConv(tp->next) ? MATCHconvert : MATCHnomatch;
    }

    if (to->ty == Tarray)
    {
        TypeDArray *ta = (TypeDArray *)to;

        if (!MODimplicitConv(next->mod, ta->next->mod))
            return MATCHnomatch;        // not const-compatible

        // Check head inout conversion:
        //       T [] -> inout(const(T)[])
        // const(T)[] -> inout(const(T)[])
        if (isMutable() && ta->isWild())
            if ((next->isMutable() || next->isConst()) && ta->next->isConst())
                return MATCHnomatch;

        /* Allow conversion to void[]
         */
        if (next->ty != Tvoid && ta->next->ty == Tvoid)
        {
            return MATCHconvert;
        }

        MATCH m = next->constConv(ta->next);
        if (m != MATCHnomatch)
        {
            if (m == MATCHexact && mod != to->mod)
                m = MATCHconst;
            return m;
        }
    }
    return Type::implicitConvTo(to);
}

Expression *TypeDArray::defaultInit(Loc loc)
{
#if LOGDEFAULTINIT
    printf("TypeDArray::defaultInit() '%s'\n", toChars());
#endif
    return new NullExp(loc, this);
}

int TypeDArray::isZeroInit(Loc loc)
{
    return 1;
}

int TypeDArray::checkBoolean()
{
    return TRUE;
}

int TypeDArray::hasPointers()
{
    return TRUE;
}


/***************************** TypeAArray *****************************/

TypeAArray::TypeAArray(Type *t, Type *index)
    : TypeArray(Taarray, t)
{
    this->index = index;
    this->impl = NULL;
    this->loc = Loc();
    this->sc = NULL;
}

const char *TypeAArray::kind()
{
    return "aarray";
}

Type *TypeAArray::syntaxCopy()
{
    Type *t = next->syntaxCopy();
    Type *ti = index->syntaxCopy();
    if (t == next && ti == index)
        t = this;
    else
    {   t = new TypeAArray(t, ti);
        t->mod = mod;
    }
    return t;
}

d_uns64 TypeAArray::size(Loc loc)
{
    return Target::ptrsize /* * 2*/;
}


Type *TypeAArray::semantic(Loc loc, Scope *sc)
{
    //printf("TypeAArray::semantic() %s index->ty = %d\n", toChars(), index->ty);
    if (deco)
        return this;

    this->loc = loc;
    this->sc = sc;
    if (sc)
        sc->setNoFree();

    // Deal with the case where we thought the index was a type, but
    // in reality it was an expression.
    if (index->ty == Tident || index->ty == Tinstance || index->ty == Tsarray)
    {
        Expression *e;
        Type *t;
        Dsymbol *s;

        index->resolve(loc, sc, &e, &t, &s);
        if (e)
        {   // It was an expression -
            // Rewrite as a static array
            TypeSArray *tsa;

            tsa = new TypeSArray(next, e);
            return tsa->semantic(loc,sc);
        }
        else if (t)
            index = t;
        else
        {   index->error(loc, "index is not a type or an expression");
            return Type::terror;
        }
    }
    else
        index = index->semantic(loc,sc);

    if (index->nextOf() && !index->nextOf()->isImmutable())
    {
        index = index->constOf()->mutableOf();
#if 0
printf("index is %p %s\n", index, index->toChars());
index->check();
printf("index->mod = x%x\n", index->mod);
printf("index->ito = x%x\n", index->ito);
if (index->ito) {
printf("index->ito->mod = x%x\n", index->ito->mod);
printf("index->ito->ito = x%x\n", index->ito->ito);
}
#endif
    }

    switch (index->toBasetype()->ty)
    {
        case Tfunction:
        case Tvoid:
        case Tnone:
        case Ttuple:
            error(loc, "can't have associative array key of %s", index->toBasetype()->toChars());
        case Terror:
            return Type::terror;
    }
    next = next->semantic(loc,sc);
    transitive();

    switch (next->toBasetype()->ty)
    {
        case Tfunction:
        case Tvoid:
        case Tnone:
            error(loc, "can't have associative array of %s", next->toChars());
        case Terror:
            return Type::terror;
    }
    if (next->isscope())
    {   error(loc, "cannot have array of scope %s", next->toChars());
        return Type::terror;
    }
    return merge();
}

StructDeclaration *TypeAArray::getImpl()
{
    // Do it lazily
    if (!impl)
    {
        Type *index = this->index;
        Type *next = this->next;
        if (index->reliesOnTident() || next->reliesOnTident())
        {
            error(loc, "cannot create associative array %s", toChars());
            index = terror;
            next = terror;

            // Head off future failures
            StructDeclaration *s = new StructDeclaration(Loc(), NULL);
            s->type = terror;
            impl = s;
            return impl;
        }
        /* This is really a proxy for the template instance AssocArray!(index, next)
         * But the instantiation can fail if it is a template specialization field
         * which has Tident's instead of real types.
         */
        Objects *tiargs = new Objects();
        tiargs->push(index->substWildTo(MODconst)); // hack for bug7757
        tiargs->push(next ->substWildTo(MODconst)); // hack for bug7757

        // Create AssociativeArray!(index, next)
#if 1
        if (! Type::associativearray)
        {
            ObjectNotFound(Id::AssociativeArray);
        }
        TemplateInstance *ti = new TemplateInstance(loc, Type::associativearray, tiargs);
#else
        //Expression *e = new IdentifierExp(loc, Id::object);
        Expression *e = new IdentifierExp(loc, Id::empty);
        //e = new DotIdExp(loc, e, Id::object);
        DotTemplateInstanceExp *dti = new DotTemplateInstanceExp(loc,
                    e,
                    Id::AssociativeArray,
                    tiargs);
        dti->semantic(sc);
        TemplateInstance *ti = dti->ti;
#endif
        // Instantiate on the root module of import dependency graph.
        Scope *scx = sc->push(sc->module->importedFrom);
        ti->semantic(scx);
        ti->semantic2(scx);
        ti->semantic3(scx);
        scx->pop();
        impl = ti->toAlias()->isStructDeclaration();
#ifdef DEBUG
        if (!impl)
        {   Dsymbol *s = ti->toAlias();
            printf("%s %s\n", s->kind(), s->toChars());
        }
#endif
        assert(impl);
    }
    return impl;
}

void TypeAArray::resolve(Loc loc, Scope *sc, Expression **pe, Type **pt, Dsymbol **ps)
{
    //printf("TypeAArray::resolve() %s\n", toChars());

    // Deal with the case where we thought the index was a type, but
    // in reality it was an expression.
    if (index->ty == Tident || index->ty == Tinstance || index->ty == Tsarray)
    {
        Expression *e;
        Type *t;
        Dsymbol *s;

        index->resolve(loc, sc, &e, &t, &s);
        if (e)
        {   // It was an expression -
            // Rewrite as a static array

            TypeSArray *tsa = new TypeSArray(next, e);
            return tsa->addMod(this->mod)->resolve(loc, sc, pe, pt, ps);
        }
        else if (t)
            index = t;
        else
            index->error(loc, "index is not a type or an expression");
    }
    Type::resolve(loc, sc, pe, pt, ps);
}


Expression *TypeAArray::dotExp(Scope *sc, Expression *e, Identifier *ident, int flag)
{
#if LOGDOTEXP
    printf("TypeAArray::dotExp(e = '%s', ident = '%s')\n", e->toChars(), ident->toChars());
#endif
    if (ident != Id::__sizeof &&
        ident != Id::__xalignof &&
        ident != Id::init &&
        ident != Id::mangleof &&
        ident != Id::stringof &&
        ident != Id::offsetof)
    {
        Type *t = getImpl()->type;
        e = e->copy();
        e->type = t;
        e = t->dotExp(sc, e, ident, flag);
    }
    else
        e = Type::dotExp(sc, e, ident, flag);
    return e;
}

void TypeAArray::toDecoBuffer(OutBuffer *buf, int flag)
{
    Type::toDecoBuffer(buf, flag);
    index->toDecoBuffer(buf);
    next->toDecoBuffer(buf, (flag & 0x100) ? 0 : mod);
}

void TypeAArray::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    next->toCBuffer2(buf, hgs, this->mod);
    buf->writeByte('[');
    index->toCBuffer2(buf, hgs, 0);
    buf->writeByte(']');
}

Expression *TypeAArray::defaultInit(Loc loc)
{
#if LOGDEFAULTINIT
    printf("TypeAArray::defaultInit() '%s'\n", toChars());
#endif
    return new NullExp(loc, this);
}

int TypeAArray::isZeroInit(Loc loc)
{
    return TRUE;
}

int TypeAArray::checkBoolean()
{
    return TRUE;
}

Expression *TypeAArray::toExpression()
{
    Expression *e = next->toExpression();
    if (e)
    {
        Expression *ei = index->toExpression();
        if (ei)
        {
            Expressions *arguments = new Expressions();
            arguments->push(ei);
            return new ArrayExp(loc, e, arguments);
        }
    }
    return NULL;
}

int TypeAArray::hasPointers()
{
    return TRUE;
}

MATCH TypeAArray::implicitConvTo(Type *to)
{
    //printf("TypeAArray::implicitConvTo(to = %s) this = %s\n", to->toChars(), toChars());
    if (equals(to))
        return MATCHexact;

    if (to->ty == Taarray)
    {   TypeAArray *ta = (TypeAArray *)to;

        if (!MODimplicitConv(next->mod, ta->next->mod))
            return MATCHnomatch;        // not const-compatible

        if (!MODimplicitConv(index->mod, ta->index->mod))
            return MATCHnomatch;        // not const-compatible

        // Check head inout conversion:
        //       V [K] -> inout(const(V)[K])
        // const(V)[K] -> inout(const(V)[K])
        if (isMutable() && ta->isWild())
            if ((next->isMutable() || next->isConst()) && ta->next->isConst())
                return MATCHnomatch;

        MATCH m = next->constConv(ta->next);
        MATCH mi = index->constConv(ta->index);
        if (m != MATCHnomatch && mi != MATCHnomatch)
        {
            return MODimplicitConv(mod, to->mod) ? MATCHconst : MATCHnomatch;
        }
    }
    else if (to->ty == Tstruct && ((TypeStruct *)to)->sym->ident == Id::AssociativeArray)
    {
        int errs = global.startGagging();
        Type *from = getImpl()->type;
        if (global.endGagging(errs))
        {
            return MATCHnomatch;
        }
        return from->implicitConvTo(to);
    }
    return Type::implicitConvTo(to);
}

MATCH TypeAArray::constConv(Type *to)
{
    if (to->ty == Taarray)
    {
        TypeAArray *taa = (TypeAArray *)to;
        MATCH mindex = index->constConv(taa->index);
        MATCH mkey = next->constConv(taa->next);
        // Pick the worst match
        return mkey < mindex ? mkey : mindex;
    }
    return Type::constConv(to);
}

Type *TypeAArray::reliesOnTident(TemplateParameters *tparams)
{
    Type *t = TypeNext::reliesOnTident(tparams);
    if (!t)
        t = index->reliesOnTident(tparams);
    return t;
}


/***************************** TypePointer *****************************/

TypePointer::TypePointer(Type *t)
    : TypeNext(Tpointer, t)
{
}

const char *TypePointer::kind()
{
    return "pointer";
}

Type *TypePointer::syntaxCopy()
{
    Type *t = next->syntaxCopy();
    if (t == next)
        t = this;
    else
    {   t = new TypePointer(t);
        t->mod = mod;
    }
    return t;
}

Type *TypePointer::semantic(Loc loc, Scope *sc)
{
    //printf("TypePointer::semantic() %s\n", toChars());
    if (deco)
        return this;
    Type *n = next->semantic(loc, sc);
    switch (n->toBasetype()->ty)
    {
        case Ttuple:
            error(loc, "can't have pointer to %s", n->toChars());
        case Terror:
            return Type::terror;
        default:
            break;
    }
    if (n != next)
    {
        deco = NULL;
    }
    next = n;
    if (next->ty != Tfunction)
    {   transitive();
        return merge();
    }
#if 1
    return merge();
#else
    deco = merge()->deco;
    /* Don't return merge(), because arg identifiers and default args
     * can be different
     * even though the types match
     */
    return this;
#endif
}


d_uns64 TypePointer::size(Loc loc)
{
    return Target::ptrsize;
}

void TypePointer::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    //printf("TypePointer::toCBuffer2() next = %d\n", next->ty);
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    next->toCBuffer2(buf, hgs, this->mod);
    if (next->ty != Tfunction)
        buf->writeByte('*');
}

MATCH TypePointer::implicitConvTo(Type *to)
{
    //printf("TypePointer::implicitConvTo(to = %s) %s\n", to->toChars(), toChars());

    if (equals(to))
        return MATCHexact;
    if (next->ty == Tfunction)
    {
        if (to->ty == Tpointer)
        {
            TypePointer *tp = (TypePointer*)to;
            if (tp->next->ty == Tfunction)
            {
                if (next->equals(tp->next))
                    return MATCHconst;

                if (next->covariant(tp->next) == 1)
                    return MATCHconvert;
            }
            else if (tp->next->ty == Tvoid)
            {
                // Allow conversions to void*
                return MATCHconvert;
            }
        }
        return MATCHnomatch;
    }
    else if (to->ty == Tpointer)
    {
        TypePointer *tp = (TypePointer *)to;
        assert(tp->next);

        if (!MODimplicitConv(next->mod, tp->next->mod))
            return MATCHnomatch;        // not const-compatible

        // Check head inout conversion:
        //       T * -> inout(const(T)*)
        // const(T)* -> inout(const(T)*)
        if (isMutable() && tp->isWild())
            if ((next->isMutable() || next->isConst()) && tp->next->isConst())
                return MATCHnomatch;

        /* Alloc conversion to void*
         */
        if (next->ty != Tvoid && tp->next->ty == Tvoid)
        {
            return MATCHconvert;
        }

        MATCH m = next->constConv(tp->next);
        if (m != MATCHnomatch)
        {
            if (m == MATCHexact && mod != to->mod)
                m = MATCHconst;
            return m;
        }
    }
    return MATCHnomatch;
}

MATCH TypePointer::constConv(Type *to)
{
    if (next->ty == Tfunction)
    {
        if (to->nextOf() && next->equals(((TypeNext*)to)->next))
            return Type::constConv(to);
        else
            return MATCHnomatch;
    }
    return TypeNext::constConv(to);
}

int TypePointer::isscalar()
{
    return TRUE;
}

Expression *TypePointer::defaultInit(Loc loc)
{
#if LOGDEFAULTINIT
    printf("TypePointer::defaultInit() '%s'\n", toChars());
#endif
    return new NullExp(loc, this);
}

int TypePointer::isZeroInit(Loc loc)
{
    return 1;
}

int TypePointer::hasPointers()
{
    return TRUE;
}


/***************************** TypeReference *****************************/

TypeReference::TypeReference(Type *t)
    : TypeNext(Treference, t)
{
    // BUG: what about references to static arrays?
}

const char *TypeReference::kind()
{
    return "reference";
}

Type *TypeReference::syntaxCopy()
{
    Type *t = next->syntaxCopy();
    if (t == next)
        t = this;
    else
    {   t = new TypeReference(t);
        t->mod = mod;
    }
    return t;
}

Type *TypeReference::semantic(Loc loc, Scope *sc)
{
    //printf("TypeReference::semantic()\n");
    Type *n = next->semantic(loc, sc);
    if (n != next)
        deco = NULL;
    next = n;
    transitive();
    return merge();
}


d_uns64 TypeReference::size(Loc loc)
{
    return Target::ptrsize;
}

void TypeReference::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    next->toCBuffer2(buf, hgs, this->mod);
    buf->writeByte('&');
}

Expression *TypeReference::dotExp(Scope *sc, Expression *e, Identifier *ident, int flag)
{
#if LOGDOTEXP
    printf("TypeReference::dotExp(e = '%s', ident = '%s')\n", e->toChars(), ident->toChars());
#endif

    // References just forward things along
    return next->dotExp(sc, e, ident, flag);
}

Expression *TypeReference::defaultInit(Loc loc)
{
#if LOGDEFAULTINIT
    printf("TypeReference::defaultInit() '%s'\n", toChars());
#endif
    return new NullExp(loc, this);
}

int TypeReference::isZeroInit(Loc loc)
{
    return 1;
}


/***************************** TypeFunction *****************************/

TypeFunction::TypeFunction(Parameters *parameters, Type *treturn, int varargs, LINK linkage, StorageClass stc)
    : TypeNext(Tfunction, treturn)
{
//if (!treturn) *(char*)0=0;
//    assert(treturn);
    assert(0 <= varargs && varargs <= 2);
    this->parameters = parameters;
    this->varargs = varargs;
    this->linkage = linkage;
    this->inuse = 0;
    this->isnothrow = false;
    this->purity = PUREimpure;
    this->isproperty = false;
    this->isref = false;
    this->iswild = false;
    this->fargs = NULL;

    if (stc & STCpure)
        this->purity = PUREfwdref;
    if (stc & STCnothrow)
        this->isnothrow = true;
    if (stc & STCproperty)
        this->isproperty = true;

    if (stc & STCref)
        this->isref = true;

    this->trust = TRUSTdefault;
    if (stc & STCsafe)
        this->trust = TRUSTsafe;
    if (stc & STCsystem)
        this->trust = TRUSTsystem;
    if (stc & STCtrusted)
        this->trust = TRUSTtrusted;
}

const char *TypeFunction::kind()
{
    return "function";
}

TypeFunction *TypeFunction::copy()
{
    TypeFunction *tf = (TypeFunction *)mem.malloc(sizeof(TypeFunction));
    memcpy(tf, this, sizeof(TypeFunction));
    return tf;
}

Type *TypeFunction::syntaxCopy()
{
    Type *treturn = next ? next->syntaxCopy() : NULL;
    Parameters *params = Parameter::arraySyntaxCopy(parameters);
    TypeFunction *t = new TypeFunction(params, treturn, varargs, linkage);
    t->mod = mod;
    t->isnothrow = isnothrow;
    t->purity = purity;
    t->isproperty = isproperty;
    t->isref = isref;
    t->trust = trust;
    t->fargs = fargs;
    return t;
}

/*******************************
 * Covariant means that 'this' can substitute for 't',
 * i.e. a pure function is a match for an impure type.
 * Returns:
 *      0       types are distinct
 *      1       this is covariant with t
 *      2       arguments match as far as overloading goes,
 *              but types are not covariant
 *      3       cannot determine covariance because of forward references
 *      *pstc   STCxxxx which would make it covariant
 */

int Type::covariant(Type *t, StorageClass *pstc)
{
#if 0
    printf("Type::covariant(t = %s) %s\n", t->toChars(), toChars());
    printf("deco = %p, %p\n", deco, t->deco);
//    printf("ty = %d\n", next->ty);
    printf("mod = %x, %x\n", mod, t->mod);
#endif

    if (pstc)
        *pstc = 0;
    StorageClass stc = 0;

    int inoutmismatch = 0;

    TypeFunction *t1;
    TypeFunction *t2;

    if (equals(t))
        return 1;                       // covariant

    if (ty != Tfunction || t->ty != Tfunction)
        goto Ldistinct;

    t1 = (TypeFunction *)this;
    t2 = (TypeFunction *)t;

    if (t1->varargs != t2->varargs)
        goto Ldistinct;

    if (t1->parameters && t2->parameters)
    {
        size_t dim = Parameter::dim(t1->parameters);
        if (dim != Parameter::dim(t2->parameters))
            goto Ldistinct;

        for (size_t i = 0; i < dim; i++)
        {   Parameter *arg1 = Parameter::getNth(t1->parameters, i);
            Parameter *arg2 = Parameter::getNth(t2->parameters, i);

            if (!arg1->type->equals(arg2->type))
            {
                goto Ldistinct;
            }
            const StorageClass sc = STCref | STCin | STCout | STClazy;
            if ((arg1->storageClass & sc) != (arg2->storageClass & sc))
                inoutmismatch = 1;
            // We can add scope, but not subtract it
            if (!(arg1->storageClass & STCscope) && (arg2->storageClass & STCscope))
                inoutmismatch = 1;
        }
    }
    else if (t1->parameters != t2->parameters)
    {
        size_t dim1 = !t1->parameters ? 0 : t1->parameters->dim;
        size_t dim2 = !t2->parameters ? 0 : t2->parameters->dim;
        if (dim1 || dim2)
            goto Ldistinct;
    }

    // The argument lists match
    if (inoutmismatch)
        goto Lnotcovariant;
    if (t1->linkage != t2->linkage)
        goto Lnotcovariant;

  {
    // Return types
    Type *t1n = t1->next;
    Type *t2n = t2->next;

    if (!t1n || !t2n)           // happens with return type inference
        goto Lnotcovariant;

    if (t1n->equals(t2n))
        goto Lcovariant;
    if (t1n->ty == Tclass && t2n->ty == Tclass)
    {
        /* If same class type, but t2n is const, then it's
         * covariant. Do this test first because it can work on
         * forward references.
         */
        if (((TypeClass *)t1n)->sym == ((TypeClass *)t2n)->sym &&
            MODimplicitConv(t1n->mod, t2n->mod))
            goto Lcovariant;

        // If t1n is forward referenced:
        ClassDeclaration *cd = ((TypeClass *)t1n)->sym;
//        if (cd->scope)
//            cd->semantic(NULL);
        if (!cd->isBaseInfoComplete())
        {
            return 3;   // forward references
        }
    }
    if (t1n->ty == Tstruct && t2n->ty == Tstruct)
    {
        if (((TypeStruct *)t1n)->sym == ((TypeStruct *)t2n)->sym &&
            MODimplicitConv(t1n->mod, t2n->mod))
            goto Lcovariant;
    }
    else if (t1n->ty == t2n->ty && t1n->implicitConvTo(t2n))
        goto Lcovariant;
    else if (t1n->ty == Tnull && t1n->implicitConvTo(t2n) &&
             t1n->size() == t2n->size())
        goto Lcovariant;
  }
    goto Lnotcovariant;

Lcovariant:
    if (t1->isref != t2->isref)
        goto Lnotcovariant;

    /* Can convert mutable to const
     */
    if (!MODimplicitConv(t2->mod, t1->mod))
    {
#if 0//stop attribute inference with const
        // If adding 'const' will make it covariant
        if (MODimplicitConv(t2->mod, MODmerge(t1->mod, MODconst)))
            stc |= STCconst;
        else
            goto Lnotcovariant;
#else
        goto Ldistinct;
#endif
    }

    /* Can convert pure to impure, and nothrow to throw
     */
    if (!t1->purity && t2->purity)
        stc |= STCpure;

    if (!t1->isnothrow && t2->isnothrow)
        stc |= STCnothrow;

    /* Can convert safe/trusted to system
     */
    if (t1->trust <= TRUSTsystem && t2->trust >= TRUSTtrusted)
        // Should we infer trusted or safe? Go with safe.
        stc |= STCsafe;

    if (stc)
    {   if (pstc)
            *pstc = stc;
        goto Lnotcovariant;
    }

    //printf("\tcovaraint: 1\n");
    return 1;

Ldistinct:
    //printf("\tcovaraint: 0\n");
    return 0;

Lnotcovariant:
    //printf("\tcovaraint: 2\n");
    return 2;
}

void TypeFunction::toDecoBuffer(OutBuffer *buf, int flag)
{   unsigned char mc;

    //printf("TypeFunction::toDecoBuffer() this = %p %s\n", this, toChars());
    //static int nest; if (++nest == 50) *(char*)0=0;
    if (inuse)
    {   inuse = 2;              // flag error to caller
        return;
    }
    inuse++;
    MODtoDecoBuffer(buf, mod);
    switch (linkage)
    {
        case LINKd:             mc = 'F';       break;
        case LINKc:             mc = 'U';       break;
        case LINKwindows:       mc = 'W';       break;
        case LINKpascal:        mc = 'V';       break;
        case LINKcpp:           mc = 'R';       break;
        default:
            assert(0);
    }
    buf->writeByte(mc);
    if (purity || isnothrow || isproperty || isref || trust)
    {
        if (purity)
            buf->writestring("Na");
        if (isnothrow)
            buf->writestring("Nb");
        if (isref)
            buf->writestring("Nc");
        if (isproperty)
            buf->writestring("Nd");
        switch (trust)
        {
            case TRUSTtrusted:
                buf->writestring("Ne");
                break;
            case TRUSTsafe:
                buf->writestring("Nf");
                break;
            default: break;
        }
    }
    // Write argument types
    Parameter::argsToDecoBuffer(buf, parameters);
    //if (buf->data[buf->offset - 1] == '@') halt();
    buf->writeByte('Z' - varargs);      // mark end of arg list
    if(next != NULL)
        next->toDecoBuffer(buf);
    inuse--;
}

void TypeFunction::toCBuffer(OutBuffer *buf, Identifier *ident, HdrGenState *hgs)
{
    toCBufferWithAttributes(buf, ident, hgs, this, NULL);
}

void TypeFunction::toCBufferWithAttributes(OutBuffer *buf, Identifier *ident, HdrGenState* hgs, TypeFunction *attrs, TemplateDeclaration *td)
{
    //printf("TypeFunction::toCBuffer() this = %p\n", this);
    if (inuse)
    {   inuse = 2;              // flag error to caller
        return;
    }
    inuse++;

    /* Use 'storage class' style for attributes
     */
    if (attrs->mod)
    {
        MODtoBuffer(buf, attrs->mod);
        buf->writeByte(' ');
    }

    if (attrs->purity)
        buf->writestring("pure ");
    if (attrs->isnothrow)
        buf->writestring("nothrow ");
    if (attrs->isproperty)
        buf->writestring("@property ");
    if (attrs->isref)
        buf->writestring("ref ");

    switch (attrs->trust)
    {
        case TRUSTsystem:
            buf->writestring("@system ");
            break;

        case TRUSTtrusted:
            buf->writestring("@trusted ");
            break;

        case TRUSTsafe:
            buf->writestring("@safe ");
            break;
        default: break;
    }

    if (hgs->ddoc != 1)
    {
        const char *p = NULL;
        switch (attrs->linkage)
        {
            case LINKd:         p = NULL;       break;
            case LINKc:         p = "C";        break;
            case LINKwindows:   p = "Windows";  break;
            case LINKpascal:    p = "Pascal";   break;
            case LINKcpp:       p = "C++";      break;
            default:
                assert(0);
        }
        if (!hgs->hdrgen && p)
        {
            buf->writestring("extern (");
            buf->writestring(p);
            buf->writestring(") ");
        }
    }

    if (!ident || ident->toHChars2() == ident->toChars())
    {   if (next)
            next->toCBuffer2(buf, hgs, 0);
        else if (hgs->ddoc)
            buf->writestring("auto");
    }

    if (ident)
    {
        if (next || hgs->ddoc)
            buf->writeByte(' ');
        buf->writestring(ident->toHChars2());
    }

    if (td)
    {   buf->writeByte('(');
        for (size_t i = 0; i < td->origParameters->dim; i++)
        {
            TemplateParameter *tp = (*td->origParameters)[i];
            if (i)
                buf->writestring(", ");
            tp->toCBuffer(buf, hgs);
        }
        buf->writeByte(')');
    }
    Parameter::argsToCBuffer(buf, hgs, parameters, varargs);
    inuse--;
}

// kind is inserted before the argument list and will usually be "function" or "delegate".
void functionToCBuffer2(TypeFunction *t, OutBuffer *buf, HdrGenState *hgs, int mod, const char *kind)
{
    if (hgs->ddoc != 1)
    {
        const char *p = NULL;
        switch (t->linkage)
        {
            case LINKd:         p = NULL;       break;
            case LINKc:         p = "C";        break;
            case LINKwindows:   p = "Windows";  break;
            case LINKpascal:    p = "Pascal";   break;
            case LINKcpp:       p = "C++";      break;
            default:
                assert(0);
        }
        if (!hgs->hdrgen && p)
        {
            buf->writestring("extern (");
            buf->writestring(p);
            buf->writestring(") ");
        }
    }
    if (t->next)
    {
        t->next->toCBuffer2(buf, hgs, 0);
        buf->writeByte(' ');
    }
    buf->writestring(kind);
    Parameter::argsToCBuffer(buf, hgs, t->parameters, t->varargs);
    t->attributesToCBuffer(buf, mod);
}

void TypeFunction::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    //printf("TypeFunction::toCBuffer2() this = %p, ref = %d\n", this, isref);
    if (inuse)
    {   inuse = 2;              // flag error to caller
        return;
    }
    inuse++;

    functionToCBuffer2(this, buf, hgs, mod, "function");

    inuse--;
}

void TypeFunction::attributesToCBuffer(OutBuffer *buf, int mod)
{
    /* Use postfix style for attributes
     */
    if (mod != this->mod)
    {
        modToBuffer(buf);
    }
    if (purity)
        buf->writestring(" pure");
    if (isnothrow)
        buf->writestring(" nothrow");
    if (isproperty)
        buf->writestring(" @property");
    if (isref)
        buf->writestring(" ref");

    switch (trust)
    {
        case TRUSTsystem:
            buf->writestring(" @system");
            break;

        case TRUSTtrusted:
            buf->writestring(" @trusted");
            break;

        case TRUSTsafe:
            buf->writestring(" @safe");
            break;
        default: break;
    }
}

Type *TypeFunction::semantic(Loc loc, Scope *sc)
{
    if (deco)                   // if semantic() already run
    {
        //printf("already done\n");
        return this;
    }
    //printf("TypeFunction::semantic() this = %p\n", this);
    //printf("TypeFunction::semantic() %s, sc->stc = %llx, fargs = %p\n", toChars(), sc->stc, fargs);

    /* Copy in order to not mess up original.
     * This can produce redundant copies if inferring return type,
     * as semantic() will get called again on this.
     */
    TypeFunction *tf = copy();
    if (parameters)
    {   tf->parameters = (Parameters *)parameters->copy();
        for (size_t i = 0; i < parameters->dim; i++)
        {   Parameter *arg = (*parameters)[i];
            Parameter *cpy = (Parameter *)mem.malloc(sizeof(Parameter));
            memcpy(cpy, arg, sizeof(Parameter));
            (*tf->parameters)[i] = cpy;
        }
    }

    if (sc->stc & STCpure)
        tf->purity = PUREfwdref;
    if (sc->stc & STCnothrow)
        tf->isnothrow = TRUE;
    if (sc->stc & STCref)
        tf->isref = TRUE;

    if (sc->stc & STCsafe)
        tf->trust = TRUSTsafe;
    if (sc->stc & STCsystem)
        tf->trust = TRUSTsystem;
    if (sc->stc & STCtrusted)
        tf->trust = TRUSTtrusted;

    if (sc->stc & STCproperty)
        tf->isproperty = TRUE;

    tf->linkage = sc->linkage;
#if 0
    /* If the parent is @safe, then this function defaults to safe
     * too.
     * If the parent's @safe-ty is inferred, then this function's @safe-ty needs
     * to be inferred first.
     */
    if (tf->trust == TRUSTdefault)
        for (Dsymbol *p = sc->func; p; p = p->toParent2())
        {   FuncDeclaration *fd = p->isFuncDeclaration();
            if (fd)
            {
                if (fd->isSafeBypassingInference())
                    tf->trust = TRUSTsafe;              // default to @safe
                break;
            }
        }
#endif
    bool wildreturn = FALSE;
    if (tf->next)
    {
        sc = sc->push();
        sc->stc &= ~(STC_TYPECTOR | STC_FUNCATTR);
        tf->next = tf->next->semantic(loc,sc);
        sc = sc->pop();
        if (tf->next->toBasetype()->ty == Tfunction)
        {   error(loc, "functions cannot return a function");
            tf->next = Type::terror;
        }
        if (tf->next->toBasetype()->ty == Ttuple)
        {   error(loc, "functions cannot return a tuple");
            tf->next = Type::terror;
        }
        if (tf->next->isscope() && !(sc->flags & SCOPEctor))
            error(loc, "functions cannot return scope %s", tf->next->toChars());
        if (tf->next->toBasetype()->ty == Tvoid)
            tf->isref = FALSE;                  // rewrite "ref void" as just "void"
        if (tf->next->hasWild() &&
            !(tf->next->ty == Tpointer && tf->next->nextOf()->ty == Tfunction || tf->next->ty == Tdelegate))
            wildreturn = TRUE;
    }

    bool wildparams = FALSE;
    if (tf->parameters)
    {
        /* Create a scope for evaluating the default arguments for the parameters
         */
        Scope *argsc = sc->push();
        argsc->stc = 0;                 // don't inherit storage class
        argsc->protection = PROTpublic;
        argsc->func = NULL;

        size_t dim = Parameter::dim(tf->parameters);
        for (size_t i = 0; i < dim; i++)
        {   Parameter *fparam = Parameter::getNth(tf->parameters, i);

            tf->inuse++;
            fparam->type = fparam->type->semantic(loc, argsc);
            if (tf->inuse == 1) tf->inuse--;

            fparam->type = fparam->type->addStorageClass(fparam->storageClass);

            if (fparam->storageClass & (STCauto | STCalias | STCstatic))
            {
                if (!fparam->type)
                    continue;
            }

            Type *t = fparam->type->toBasetype();

            if (fparam->storageClass & (STCout | STCref | STClazy))
            {
                //if (t->ty == Tsarray)
                    //error(loc, "cannot have out or ref parameter of type %s", t->toChars());
                if (fparam->storageClass & STCout && fparam->type->mod & (STCconst | STCimmutable))
                    error(loc, "cannot have const or immutable out parameter of type %s", t->toChars());
            }
            if (!(fparam->storageClass & STClazy) && t->ty == Tvoid)
                error(loc, "cannot have parameter of type %s", fparam->type->toChars());

            if (t->hasWild() &&
                !(t->ty == Tpointer && t->nextOf()->ty == Tfunction || t->ty == Tdelegate))
            {
                wildparams = TRUE;
                //if (tf->next && !wildreturn)
                //    error(loc, "inout on parameter means inout must be on return type as well (if from D1 code, replace with 'ref')");
            }

            if (fparam->defaultArg)
            {   Expression *e = fparam->defaultArg;
                Initializer *init = new ExpInitializer(e->loc, e);
                init = init->semantic(argsc, fparam->type, INITnointerpret);
                e = init->toExpression();
                if (e->op == TOKfunction)               // see Bugzilla 4820
                {   FuncExp *fe = (FuncExp *)e;
                    // Replace function literal with a function symbol,
                    // since default arg expression must be copied when used
                    // and copying the literal itself is wrong.
                    e = new VarExp(e->loc, fe->fd, 0);
                    e = new AddrExp(e->loc, e);
                    e = e->semantic(argsc);
                }
                e = e->implicitCastTo(argsc, fparam->type);

                // default arg must be an lvalue
                if (fparam->storageClass & (STCout | STCref))
                    e = e->toLvalue(argsc, e);

                fparam->defaultArg = e;
            }

            /* If fparam after semantic() turns out to be a tuple, the number of parameters may
             * change.
             */
            if (t->ty == Ttuple)
            {
                /* TypeFunction::parameter also is used as the storage of
                 * Parameter objects for FuncDeclaration. So we should copy
                 * the elements of TypeTuple::arguments to avoid unintended
                 * sharing of Parameter object among other functions.
                 */
                TypeTuple *tt = (TypeTuple *)t;
                if (tt->arguments && tt->arguments->dim)
                {
                    /* Propagate additional storage class from tuple parameters to their
                     * element-parameters.
                     * Make a copy, as original may be referenced elsewhere.
                     */
                    size_t tdim = tt->arguments->dim;
                    Parameters *newparams = new Parameters();
                    newparams->setDim(tdim);
                    for (size_t j = 0; j < tdim; j++)
                    {   Parameter *narg = (*tt->arguments)[j];
                        (*newparams)[j] = new Parameter(narg->storageClass | fparam->storageClass,
                                narg->type, narg->ident, narg->defaultArg);
                    }
                    fparam->type = new TypeTuple(newparams);
                }
                fparam->storageClass = 0;

                /* Reset number of parameters, and back up one to do this fparam again,
                 * now that it is a tuple
                 */
                dim = Parameter::dim(tf->parameters);
                i--;
                continue;
            }

            /* Resolve "auto ref" storage class to be either ref or value,
             * based on the argument matching the parameter
             */
            if (fparam->storageClass & STCauto)
            {
                if (fargs && i < fargs->dim)
                {   Expression *farg = (*fargs)[i];
                    if (farg->isLvalue())
                        ;                               // ref parameter
                    else
                        fparam->storageClass &= ~STCref;        // value parameter
                }
                else
                    error(loc, "auto can only be used for template function parameters");
            }

            // Remove redundant storage classes for type, they are already applied
            fparam->storageClass &= ~(STC_TYPECTOR | STCin);
        }
        argsc->pop();
    }
    if (tf->isWild())
        wildparams = TRUE;

    if (wildreturn && !wildparams)
        error(loc, "inout on return means inout must be on a parameter as well for %s", toChars());
    tf->iswild = wildparams;

    if (tf->next)
        tf->deco = tf->merge()->deco;

    if (tf->inuse)
    {   error(loc, "recursive type");
        tf->inuse = 0;
        return terror;
    }

    if (tf->isproperty && (tf->varargs || Parameter::dim(tf->parameters) > 2))
        error(loc, "properties can only have zero, one, or two parameter");

    if (tf->varargs == 1 && tf->linkage != LINKd && Parameter::dim(tf->parameters) == 0)
        error(loc, "variadic functions with non-D linkage must have at least one parameter");

    /* Don't return merge(), because arg identifiers and default args
     * can be different
     * even though the types match
     */
    return tf;
}


/********************************************
 * Do this lazily, as the parameter types might be forward referenced.
 */
void TypeFunction::purityLevel()
{
    TypeFunction *tf = this;
    if (tf->purity == PUREfwdref)
    {   /* Evaluate what kind of purity based on the modifiers for the parameters
         */
        tf->purity = PUREstrong;        // assume strong until something weakens it
        if (tf->parameters)
        {
            size_t dim = Parameter::dim(tf->parameters);
            for (size_t i = 0; i < dim; i++)
            {   Parameter *fparam = Parameter::getNth(tf->parameters, i);
                if (fparam->storageClass & STClazy)
                {
                    tf->purity = PUREweak;
                    break;
                }
                if (fparam->storageClass & STCout)
                {
                    tf->purity = PUREweak;
                    break;
                }
                if (!fparam->type)
                    continue;
                if (fparam->storageClass & STCref)
                {
                    if (!(fparam->type->mod & (MODconst | MODimmutable | MODwild)))
                    {   tf->purity = PUREweak;
                        break;
                    }
                    if (fparam->type->mod & MODconst)
                    {   tf->purity = PUREconst;
                        continue;
                    }
                }
                Type *t = fparam->type->toBasetype();
                if (!t->hasPointers())
                    continue;
                if (t->mod & MODimmutable)
                    continue;
                /* The rest of this is too strict; fix later.
                 * For example, the only pointer members of a struct may be immutable,
                 * which would maintain strong purity.
                 */
                if (t->mod & (MODconst | MODwild))
                {   tf->purity = PUREconst;
                    continue;
                }
                Type *tn = t->nextOf();
                if (tn)
                {   tn = tn->toBasetype();
                    if (tn->ty == Tpointer || tn->ty == Tarray)
                    {   /* Accept immutable(T)* and immutable(T)[] as being strongly pure
                         */
                        if (tn->mod & MODimmutable)
                            continue;
                        if (tn->mod & (MODconst | MODwild))
                        {   tf->purity = PUREconst;
                            continue;
                        }
                    }
                }
                /* Should catch delegates and function pointers, and fold in their purity
                 */
                tf->purity = PUREweak;          // err on the side of too strict
                break;
            }
        }
    }
}


/********************************
 * 'args' are being matched to function 'this'
 * Determine match level.
 * Input:
 *      flag    1       performing a partial ordering match
 * Returns:
 *      MATCHxxxx
 */

MATCH TypeFunction::callMatch(Type *tthis, Expressions *args, int flag)
{
    //printf("TypeFunction::callMatch() %s\n", toChars());
    MATCH match = MATCHexact;           // assume exact match
    unsigned wildmatch = 0;

    if (tthis)
    {   Type *t = tthis;
        if (t->toBasetype()->ty == Tpointer)
            t = t->toBasetype()->nextOf();      // change struct* to struct
        if (t->mod != mod)
        {
            if (MODimplicitConv(t->mod, mod))
                match = MATCHconst;
            else if ((mod & MODwild)
                && MODimplicitConv(t->mod, (mod & ~MODwild) | MODconst))
            {
                match = MATCHconst;
            }
            else
                return MATCHnomatch;
        }
        if (isWild())
        {
            if (t->isWild())
                wildmatch |= MODwild;
            else if (t->isConst())
                wildmatch |= MODconst;
            else if (t->isImmutable())
                wildmatch |= MODimmutable;
            else
                wildmatch |= MODmutable;
        }
    }

    size_t nparams = Parameter::dim(parameters);
    size_t nargs = args ? args->dim : 0;
    if (nparams == nargs)
        ;
    else if (nargs > nparams)
    {
        if (varargs == 0)
            goto Nomatch;               // too many args; no match
        match = MATCHconvert;           // match ... with a "conversion" match level
    }

    for (size_t u = 0; u < nargs; u++)
    {
        if (u >= nparams)
            break;
        Parameter *p = Parameter::getNth(parameters, u);
        Expression *arg = (*args)[u];
        assert(arg);

        if (!(p->storageClass & STClazy && p->type->ty == Tvoid && arg->type->ty != Tvoid))
        {
            unsigned mod = arg->type->wildConvTo(p->type);
            if (mod)
            {
                wildmatch |= mod;
            }
        }
    }
    if (wildmatch)
    {   /* Calculate wild matching modifier
         */
        if (wildmatch & MODconst || wildmatch & (wildmatch - 1))
            wildmatch = MODconst;
        else if (wildmatch & MODimmutable)
            wildmatch = MODimmutable;
        else if (wildmatch & MODwild)
            wildmatch = MODwild;
        else
        {   assert(wildmatch & MODmutable);
            wildmatch = MODmutable;
        }
    }

    for (size_t u = 0; u < nparams; u++)
    {   MATCH m;

        // BUG: what about out and ref?

        Parameter *p = Parameter::getNth(parameters, u);
        assert(p);
        if (u >= nargs)
        {
            if (p->defaultArg)
                continue;
            goto L1;        // try typesafe variadics
        }
        {
        Expression *arg = (*args)[u];
        assert(arg);
        if (Expression *e = arg->isTemp())
            arg = e;

        if (arg->op == TOKfunction)
        {
            arg = ((FuncExp *)arg)->inferType(p->type, 1);
            if (!arg)
                goto L1;    // try typesafe variadics
        }

        //printf("arg: %s, type: %s\n", arg->toChars(), arg->type->toChars());

        Type *targ = arg->type;
        Type *tprm = wildmatch ? p->type->substWildTo(wildmatch) : p->type;

        if (p->storageClass & STClazy && tprm->ty == Tvoid && targ->ty != Tvoid)
            m = MATCHconvert;
        else
        {
            //printf("%s of type %s implicitConvTo %s\n", arg->toChars(), targ->toChars(), tprm->toChars());
            if (flag)
                // for partial ordering, value is an irrelevant mockup, just look at the type
                m = targ->implicitConvTo(tprm);
            else
                m = arg->implicitConvTo(tprm);
            //printf("match %d\n", m);
        }

        // Non-lvalues do not match ref or out parameters
        if (p->storageClass & STCref)
        {
            Type *targb = targ->toBasetype();
            Type *tprmb = tprm->toBasetype();
            //printf("%s\n", targb->toChars());
            //printf("%s\n", tprmb->toChars());

            if (m && !arg->isLvalue())
            {
                if (arg->op == TOKstring && tprmb->ty == Tsarray)
                {   if (targb->ty != Tsarray)
                        {
                        targb = new TypeSArray(tprmb->nextOf()->castMod(targb->nextOf()->mod),
                                new IntegerExp(Loc(), ((StringExp *)arg)->len,
                                Type::tindex));
                        targb = targb->semantic(Loc(), NULL);
                    }
                }
                else if (arg->op == TOKslice && tprmb->ty == Tsarray)
                {   // Allow conversion from T[lwr .. upr] to ref T[upr-lwr]
                    targb = new TypeSArray(targb->nextOf(),
                            new IntegerExp(Loc(), ((TypeSArray *)tprmb)->dim->toUInteger(),
                            Type::tindex));
                    targb = targb->semantic(Loc(), NULL);
                }
                else
                    goto Nomatch;
            }

            /* find most derived alias this type being matched.
             */
            while (1)
            {
                Type *tat = targb->aliasthisOf();
                if (!tat || !tat->implicitConvTo(tprm))
                    break;
                targb = tat;
            }

            /* Don't allow static arrays to be passed to mutable references
             * to static arrays if the argument cannot be modified.
             */
            if (targb->nextOf() && tprmb->ty == Tsarray &&
                !MODimplicitConv(targb->nextOf()->mod, tprmb->nextOf()->mod))
                goto Nomatch;

            // ref variable behaves like head-const reference
            if (!targb->constConv(tprmb))
                goto Nomatch;
        }
        else if (p->storageClass & STCout)
        {   if (m && !arg->isLvalue())
                goto Nomatch;
        }
        }

        /* prefer matching the element type rather than the array
         * type when more arguments are present with T[]...
         */
        if (varargs == 2 && u + 1 == nparams && nargs > nparams)
            goto L1;

        //printf("\tm = %d\n", m);
        if (m == MATCHnomatch)                  // if no match
        {
          L1:
            if (varargs == 2 && u + 1 == nparams)       // if last varargs param
            {   Type *tb = p->type->toBasetype();
                TypeSArray *tsa;
                dinteger_t sz;

                switch (tb->ty)
                {
                    case Tsarray:
                        tsa = (TypeSArray *)tb;
                        sz = tsa->dim->toInteger();
                        if (sz != nargs - u)
                            goto Nomatch;
                    case Tarray:
                    {   TypeArray *ta = (TypeArray *)tb;
                        for (; u < nargs; u++)
                        {
                            Expression *arg = (*args)[u];
                            assert(arg);
                            if (arg->op == TOKfunction)
                            {
                                arg = ((FuncExp *)arg)->inferType(tb->nextOf(), 1);
                                if (!arg)
                                    goto Nomatch;
                            }

                            /* If lazy array of delegates,
                             * convert arg(s) to delegate(s)
                             */
                            Type *tret = p->isLazyArray();
                            if (tret)
                            {
                                if (ta->next->equals(arg->type))
                                    m = MATCHexact;
                                else if (tret->toBasetype()->ty == Tvoid)
                                    m = MATCHconvert;
                                else
                                {
                                    m = arg->implicitConvTo(tret);
                                    if (m == MATCHnomatch)
                                        m = arg->implicitConvTo(ta->next);
                                }
                            }
                            else
                                m = arg->implicitConvTo(ta->next);

                            if (m == MATCHnomatch)
                                goto Nomatch;
                            if (m < match)
                                match = m;
                        }
                        goto Ldone;
                    }
                    case Tclass:
                        // Should see if there's a constructor match?
                        // Or just leave it ambiguous?
                        goto Ldone;

                    default:
                        goto Nomatch;
                }
            }
            goto Nomatch;
        }
        if (m < match)
            match = m;                  // pick worst match
    }

Ldone:
    //printf("match = %d\n", match);
    return match;

Nomatch:
    //printf("no match\n");
    return MATCHnomatch;
}

Type *TypeFunction::reliesOnTident(TemplateParameters *tparams)
{
    size_t dim = Parameter::dim(parameters);
    for (size_t i = 0; i < dim; i++)
    {   Parameter *fparam = Parameter::getNth(parameters, i);
        Type *t = fparam->type->reliesOnTident(tparams);
        if (t)
            return t;
    }
    return next ? next->reliesOnTident(tparams) : NULL;
}

/********************************************
 * Return TRUE if there are lazy parameters.
 */
bool TypeFunction::hasLazyParameters()
{
    size_t dim = Parameter::dim(parameters);
    for (size_t i = 0; i < dim; i++)
    {   Parameter *fparam = Parameter::getNth(parameters, i);
        if (fparam->storageClass & STClazy)
            return TRUE;
    }
    return FALSE;
}

/***************************
 * Examine function signature for parameter p and see if
 * p can 'escape' the scope of the function.
 */

bool TypeFunction::parameterEscapes(Parameter *p)
{

    /* Scope parameters do not escape.
     * Allow 'lazy' to imply 'scope' -
     * lazy parameters can be passed along
     * as lazy parameters to the next function, but that isn't
     * escaping.
     */
    if (p->storageClass & (STCscope | STClazy))
        return FALSE;

    /* If haven't inferred the return type yet, assume it escapes
     */
    if (!nextOf())
        return TRUE;

    if (purity > PUREweak)
    {   /* With pure functions, we need only be concerned if p escapes
         * via any return statement.
         */
        Type* tret = nextOf()->toBasetype();
        if (!isref && !tret->hasPointers())
        {   /* The result has no references, so p could not be escaping
             * that way.
             */
            return FALSE;
        }
    }

    /* Assume it escapes in the absence of better information.
     */
    return TRUE;
}

Expression *TypeFunction::defaultInit(Loc loc)
{
    error(loc, "function does not have a default initializer");
    return new ErrorExp();
}

Type *TypeFunction::addStorageClass(StorageClass stc)
{
    TypeFunction *t = (TypeFunction *)Type::addStorageClass(stc);
    if ((stc & STCpure && !t->purity) ||
        (stc & STCnothrow && !t->isnothrow) ||
        (stc & STCsafe && t->trust < TRUSTtrusted))
    {
        // Klunky to change these
        TypeFunction *tf = new TypeFunction(t->parameters, t->next, t->varargs, t->linkage, 0);
        tf->mod = t->mod;
        tf->fargs = fargs;
        tf->purity = t->purity;
        tf->isnothrow = t->isnothrow;
        tf->isproperty = t->isproperty;
        tf->isref = t->isref;
        tf->trust = t->trust;
        tf->iswild = t->iswild;

        if (stc & STCpure)
            tf->purity = PUREfwdref;
        if (stc & STCnothrow)
            tf->isnothrow = true;
        if (stc & STCsafe)
            tf->trust = TRUSTsafe;

        tf->deco = tf->merge()->deco;
        t = tf;
    }
    return t;
}

/***************************** TypeDelegate *****************************/

TypeDelegate::TypeDelegate(Type *t)
    : TypeNext(Tfunction, t)
{
    ty = Tdelegate;
}

const char *TypeDelegate::kind()
{
    return "delegate";
}

Type *TypeDelegate::syntaxCopy()
{
    Type *t = next->syntaxCopy();
    if (t == next)
        t = this;
    else
    {   t = new TypeDelegate(t);
        t->mod = mod;
    }
    return t;
}

Type *TypeDelegate::semantic(Loc loc, Scope *sc)
{
    //printf("TypeDelegate::semantic() %s\n", toChars());
    if (deco)                   // if semantic() already run
    {
        //printf("already done\n");
        return this;
    }
    next = next->semantic(loc,sc);
    /* In order to deal with Bugzilla 4028, perhaps default arguments should
     * be removed from next before the merge.
     */

#if 1
    return merge();
#else
    /* Don't return merge(), because arg identifiers and default args
     * can be different
     * even though the types match
     */
    deco = merge()->deco;
    return this;
#endif
}

d_uns64 TypeDelegate::size(Loc loc)
{
    return Target::ptrsize * 2;
}

unsigned TypeDelegate::alignsize()
{
#if DMDV1
    // See Bugzilla 942 for discussion
    if (!global.params.is64bit)
        return Target::ptrsize * 2;
#endif
    return Target::ptrsize;
}

MATCH TypeDelegate::implicitConvTo(Type *to)
{
    //printf("TypeDelegate::implicitConvTo(this=%p, to=%p)\n", this, to);
    //printf("from: %s\n", toChars());
    //printf("to  : %s\n", to->toChars());
    if (this == to)
        return MATCHexact;
#if 1 // not allowing covariant conversions because it interferes with overriding
    if (to->ty == Tdelegate && this->nextOf()->covariant(to->nextOf()) == 1)
        return MATCHconvert;
#endif
    return MATCHnomatch;
}

void TypeDelegate::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }

    functionToCBuffer2((TypeFunction *)next, buf, hgs, mod, "delegate");
}

Expression *TypeDelegate::defaultInit(Loc loc)
{
#if LOGDEFAULTINIT
    printf("TypeDelegate::defaultInit() '%s'\n", toChars());
#endif
    return new NullExp(loc, this);
}

int TypeDelegate::isZeroInit(Loc loc)
{
    return 1;
}

int TypeDelegate::checkBoolean()
{
    return TRUE;
}

Expression *TypeDelegate::dotExp(Scope *sc, Expression *e, Identifier *ident, int flag)
{
#if LOGDOTEXP
    printf("TypeDelegate::dotExp(e = '%s', ident = '%s')\n", e->toChars(), ident->toChars());
#endif
    if (ident == Id::ptr)
    {
        e->type = tvoidptr;
        return e;
    }
    else if (ident == Id::funcptr)
    {
        if (!e->isLvalue())
        {
            Identifier *idtmp = Lexer::uniqueId("__dgtmp");
            VarDeclaration *tmp = new VarDeclaration(e->loc, this, idtmp, new ExpInitializer(Loc(), e));
            tmp->storage_class |= STCctfe;
            e = new DeclarationExp(e->loc, tmp);
            e = new CommaExp(e->loc, e, new VarExp(e->loc, tmp));
            e = e->semantic(sc);
        }
        e = e->addressOf(sc);
        e->type = tvoidptr;
        e = new AddExp(e->loc, e, new IntegerExp(Target::ptrsize));
        e->type = tvoidptr;
        e = new PtrExp(e->loc, e);
        e->type = next->pointerTo();
        return e;
    }
    else
    {
        e = Type::dotExp(sc, e, ident, flag);
    }
    return e;
}

int TypeDelegate::hasPointers()
{
    return TRUE;
}



/***************************** TypeQualified *****************************/

TypeQualified::TypeQualified(TY ty, Loc loc)
    : Type(ty)
{
    this->loc = loc;
}

void TypeQualified::syntaxCopyHelper(TypeQualified *t)
{
    //printf("TypeQualified::syntaxCopyHelper(%s) %s\n", t->toChars(), toChars());
    idents.setDim(t->idents.dim);
    for (size_t i = 0; i < idents.dim; i++)
    {
        RootObject *id = t->idents[i];
        if (id->dyncast() == DYNCAST_DSYMBOL)
        {
            TemplateInstance *ti = (TemplateInstance *)id;

            ti = (TemplateInstance *)ti->syntaxCopy(NULL);
            id = ti;
        }
        idents[i] = id;
    }
}


void TypeQualified::addIdent(Identifier *ident)
{
    idents.push(ident);
}

void TypeQualified::addInst(TemplateInstance *inst)
{
    idents.push(inst);
}

void TypeQualified::toCBuffer2Helper(OutBuffer *buf, HdrGenState *hgs)
{
    for (size_t i = 0; i < idents.dim; i++)
    {   RootObject *id = idents[i];

        buf->writeByte('.');

        if (id->dyncast() == DYNCAST_DSYMBOL)
        {
            TemplateInstance *ti = (TemplateInstance *)id;
            ti->toCBuffer(buf, hgs);
        }
        else
            buf->writestring(id->toChars());
    }
}

d_uns64 TypeQualified::size(Loc loc)
{
    error(this->loc, "size of type %s is not known", toChars());
    return SIZE_INVALID;
}

/*************************************
 * Takes an array of Identifiers and figures out if
 * it represents a Type or an Expression.
 * Output:
 *      if expression, *pe is set
 *      if type, *pt is set
 */

void TypeQualified::resolveHelper(Loc loc, Scope *sc,
        Dsymbol *s, Dsymbol *scopesym,
        Expression **pe, Type **pt, Dsymbol **ps)
{
#if 0
    printf("TypeQualified::resolveHelper(sc = %p, idents = '%s')\n", sc, toChars());
    if (scopesym)
        printf("\tscopesym = '%s'\n", scopesym->toChars());
#endif
    *pe = NULL;
    *pt = NULL;
    *ps = NULL;
    if (s)
    {
        //printf("\t1: s = '%s' %p, kind = '%s'\n",s->toChars(), s, s->kind());
        s->checkDeprecated(loc, sc);            // check for deprecated aliases
        s = s->toAlias();
        //printf("\t2: s = '%s' %p, kind = '%s'\n",s->toChars(), s, s->kind());
        for (size_t i = 0; i < idents.dim; i++)
        {
            RootObject *id = idents[i];
            Dsymbol *sm = s->searchX(loc, sc, id);
            //printf("\t3: s = '%s' %p, kind = '%s'\n",s->toChars(), s, s->kind());
            //printf("\tgetType = '%s'\n", s->getType()->toChars());
            if (!sm)
            {
                Type *t = s->getType();     // type symbol, type alias, or type tuple?
                if (!t)
                {   if (s->isDeclaration())         // var, func, or tuple declaration?
                    {   t = s->isDeclaration()->type;
                        if (!t && s->isTupleDeclaration())  // expression tuple?
                            goto L3;
                    }
                    else if (s->isTemplateInstance() ||
                             s->isImport() || s->isPackage() || s->isModule())
                    {
                        goto L3;
                    }
                }
                if (t)
                {
                    sm = t->toDsymbol(sc);
                    if (sm && id->dyncast() == DYNCAST_IDENTIFIER)
                    {
                        sm = sm->search(loc, (Identifier *)id, 0);
                        if (sm)
                            goto L2;
                    }
                L3:
                    Expression *e = new DsymbolExp(loc, s);
                    e = e->semantic(sc);
                    for (; i < idents.dim; i++)
                    {
                        RootObject *id = idents[i];
                        //printf("e: '%s', id: '%s', type = %s\n", e->toChars(), id->toChars(), e->type->toChars());
                        if (id->dyncast() == DYNCAST_IDENTIFIER)
                        {
                            DotIdExp *die = new DotIdExp(e->loc, e, (Identifier *)id);
                            e = die->semanticY(sc, 0);
                        }
                        else
                        {   assert(id->dyncast() == DYNCAST_DSYMBOL);
                            TemplateInstance *ti = ((Dsymbol *)id)->isTemplateInstance();
                            assert(ti);
                            DotTemplateInstanceExp *dte = new DotTemplateInstanceExp(e->loc, e, ti->name, ti->tiargs);
                            e = dte->semanticY(sc, 0);
                        }
                    }
                    if (e->op == TOKtype)
                        *pt = e->type;
                    else
                        *pe = e;
                }
                else
                {
                  Lerror:
                    if (id->dyncast() == DYNCAST_DSYMBOL)
                    {   // searchX already handles errors for template instances
                        assert(global.errors);
                    }
                    else
                    {
                        assert(id->dyncast() == DYNCAST_IDENTIFIER);
                        sm = s->search_correct((Identifier *)id);
                        if (sm)
                            error(loc, "identifier '%s' of '%s' is not defined, did you mean '%s %s'?",
                                  id->toChars(), toChars(), sm->kind(), sm->toChars());
                        else
                            error(loc, "identifier '%s' of '%s' is not defined", id->toChars(), toChars());
                    }
                    *pe = new ErrorExp();
                }
                return;
            }
        L2:
            s = sm->toAlias();
        }

        if (VarDeclaration *v = s->isVarDeclaration())
        {
            if (v && v->inuse && (!v->type || !v->type->deco))  // Bugzilla 9494
            {   error(loc, "circular reference to '%s'", v->toPrettyChars());
                *pe = new ErrorExp();
                return;
            }
            *pe = new VarExp(loc, v);
            return;
        }
#if 0
        if (FuncDeclaration *fd = s->isFuncDeclaration())
        {
            *pe = new DsymbolExp(loc, fd, 1);
            return;
        }
#endif
        if (EnumMember *em = s->isEnumMember())
        {
            // It's not a type, it's an expression
            *pe = em->getVarExp(loc, sc);
            return;
        }

L1:
        Type *t = s->getType();
        if (!t)
        {
            // If the symbol is an import, try looking inside the import
            if (Import *si = s->isImport())
            {
                s = si->search(loc, s->ident, 0);
                if (s && s != si)
                    goto L1;
                s = si;
            }
            *ps = s;
            return;
        }
        if (t->ty == Tinstance && t != this && !t->deco)
        {   error(loc, "forward reference to '%s'", t->toChars());
            *pt = Type::terror;
            return;
        }

        if (t != this)
        {
            if (t->reliesOnTident())
            {
                if (s->scope)
                    t = t->semantic(loc, s->scope);
                else
                {
                    /* Attempt to find correct scope in which to evaluate t.
                     * Not sure if this is right or not, or if we should just
                     * give forward reference error if s->scope is not set.
                     */
                    for (Scope *scx = sc; 1; scx = scx->enclosing)
                    {
                        if (!scx)
                        {   error(loc, "forward reference to '%s'", t->toChars());
                            *pt = Type::terror;
                            return;
                        }
                        if (scx->scopesym == scopesym)
                        {
                            t = t->semantic(loc, scx);
                            break;
                        }
                    }
                }
            }
        }
        if (t->ty == Ttuple)
            *pt = t;
        else
            *pt = t->merge();
    }
    if (!s)
    {
        const char *p = toChars();
        const char *n = importHint(p);
        if (n)
            error(loc, "'%s' is not defined, perhaps you need to import %s; ?", p, n);
        else
        {
            Identifier *id = new Identifier(p, TOKidentifier);
            s = sc->search_correct(id);
            if (s)
                error(loc, "undefined identifier %s, did you mean %s %s?", p, s->kind(), s->toChars());
            else
                error(loc, "undefined identifier %s", p);
        }
        *pt = Type::terror;
    }
}

/***************************** TypeIdentifier *****************************/

TypeIdentifier::TypeIdentifier(Loc loc, Identifier *ident)
    : TypeQualified(Tident, loc)
{
    this->ident = ident;
}

const char *TypeIdentifier::kind()
{
    return "identifier";
}


Type *TypeIdentifier::syntaxCopy()
{
    TypeIdentifier *t;

    t = new TypeIdentifier(loc, ident);
    t->syntaxCopyHelper(this);
    t->mod = mod;
    return t;
}

void TypeIdentifier::toDecoBuffer(OutBuffer *buf, int flag)
{
    Type::toDecoBuffer(buf, flag);
    const char *name = ident->toChars();
    size_t len = strlen(name);
    buf->printf("%u%s", (unsigned)len, name);
}

void TypeIdentifier::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    buf->writestring(this->ident->toChars());
    toCBuffer2Helper(buf, hgs);
}

/*************************************
 * Takes an array of Identifiers and figures out if
 * it represents a Type or an Expression.
 * Output:
 *      if expression, *pe is set
 *      if type, *pt is set
 */

void TypeIdentifier::resolve(Loc loc, Scope *sc, Expression **pe, Type **pt, Dsymbol **ps)
{
    Dsymbol *scopesym;

    //printf("TypeIdentifier::resolve(sc = %p, idents = '%s')\n", sc, toChars());

    if ((ident->equals(Id::super) || ident->equals(Id::This)) && !hasThis(sc))
    {
        AggregateDeclaration *ad = sc->getStructClassScope();
        if (ad)
        {
            ClassDeclaration *cd = ad->isClassDeclaration();
            if (cd)
            {
                if (ident->equals(Id::This))
                    ident = cd->ident;
                else if (cd->baseClass && ident->equals(Id::super))
                    ident = cd->baseClass->ident;
            }
            else
            {
                StructDeclaration *sd = ad->isStructDeclaration();
                if (sd && ident->equals(Id::This))
                    ident = sd->ident;
            }
        }
    }

    Dsymbol *s = sc->search(loc, ident, &scopesym);
    resolveHelper(loc, sc, s, scopesym, pe, pt, ps);
    if (*pt)
        (*pt) = (*pt)->addMod(mod);
}

/*****************************************
 * See if type resolves to a symbol, if so,
 * return that symbol.
 */

Dsymbol *TypeIdentifier::toDsymbol(Scope *sc)
{
    //printf("TypeIdentifier::toDsymbol('%s')\n", toChars());
    if (!sc)
        return NULL;
    //printf("ident = '%s'\n", ident->toChars());

    Dsymbol *scopesym;
    Dsymbol *s = sc->search(loc, ident, &scopesym);
    if (s)
    {
        for (size_t i = 0; i < idents.dim; i++)
        {
            RootObject *id = idents[i];
            s = s->searchX(loc, sc, id);
            if (!s)                 // failed to find a symbol
            {   //printf("\tdidn't find a symbol\n");
                break;
            }
        }
    }
    return s;
}

Type *TypeIdentifier::semantic(Loc loc, Scope *sc)
{
    Type *t;
    Expression *e;
    Dsymbol *s;

    //printf("TypeIdentifier::semantic(%s)\n", toChars());
    resolve(loc, sc, &e, &t, &s);
    if (t)
    {
        //printf("\tit's a type %d, %s, %s\n", t->ty, t->toChars(), t->deco);

        if (t->ty == Ttypedef)
        {   TypeTypedef *tt = (TypeTypedef *)t;

            if (tt->sym->sem == SemanticIn)
            {   error(loc, "circular reference of typedef %s", tt->toChars());
                return terror;
            }
        }
        t = t->addMod(mod);
    }
    else
    {
        if (s)
        {
            s->error(loc, "is used as a type");
            //halt();
        }
        else
            error(loc, "%s is used as a type", toChars());
        t = terror;
    }
    //t->print();
    return t;
}

Type *TypeIdentifier::reliesOnTident(TemplateParameters *tparams)
{
    if (tparams)
    {
        if (idents.dim == 0)
        {
            for (size_t i = 0; i < tparams->dim; i++)
            {   TemplateParameter *tp = (*tparams)[i];

                if (tp->ident->equals(ident))
                    return this;
            }
        }
        return NULL;
    }
    else
        return this;
}

Expression *TypeIdentifier::toExpression()
{
    Expression *e = new IdentifierExp(loc, ident);
    for (size_t i = 0; i < idents.dim; i++)
    {
        RootObject *id = idents[i];
        if (id->dyncast() == DYNCAST_IDENTIFIER)
        {
            e = new DotIdExp(loc, e, (Identifier *)id);
        }
        else
        {   assert(id->dyncast() == DYNCAST_DSYMBOL);
            TemplateInstance *ti = ((Dsymbol *)id)->isTemplateInstance();
            assert(ti);
            e = new DotTemplateInstanceExp(loc, e, ti->name, ti->tiargs);
        }
    }

    return e;
}

/***************************** TypeInstance *****************************/

TypeInstance::TypeInstance(Loc loc, TemplateInstance *tempinst)
    : TypeQualified(Tinstance, loc)
{
    this->tempinst = tempinst;
}

const char *TypeInstance::kind()
{
    return "instance";
}

Type *TypeInstance::syntaxCopy()
{
    //printf("TypeInstance::syntaxCopy() %s, %d\n", toChars(), idents.dim);
    TypeInstance *t;

    t = new TypeInstance(loc, (TemplateInstance *)tempinst->syntaxCopy(NULL));
    t->syntaxCopyHelper(this);
    t->mod = mod;
    return t;
}


void TypeInstance::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    tempinst->toCBuffer(buf, hgs);
    toCBuffer2Helper(buf, hgs);
}

void TypeInstance::resolve(Loc loc, Scope *sc, Expression **pe, Type **pt, Dsymbol **ps)
{
    // Note close similarity to TypeIdentifier::resolve()

    Dsymbol *s;

    *pe = NULL;
    *pt = NULL;
    *ps = NULL;

#if 0
    if (!idents.dim)
    {
        error(loc, "template instance '%s' has no identifier", toChars());
        return;
    }
#endif
    //id = (Identifier *)idents.data[0];
    //printf("TypeInstance::resolve(sc = %p, idents = '%s')\n", sc, id->toChars());
    s = tempinst;
    if (s)
    {   //printf("s = %s\n", s->toChars());
        s->semantic(sc);
    }
    resolveHelper(loc, sc, s, NULL, pe, pt, ps);
    if (*pt)
        *pt = (*pt)->addMod(mod);
    //printf("pt = '%s'\n", (*pt)->toChars());
}

Type *TypeInstance::semantic(Loc loc, Scope *sc)
{
    Type *t;
    Expression *e;
    Dsymbol *s;

    //printf("TypeInstance::semantic(%p, %s)\n", this, toChars());
    {
        unsigned errors = global.errors;
        resolve(loc, sc, &e, &t, &s);
        // if we had an error evaluating the symbol, suppress further errors
        if (!t && errors != global.errors)
            return terror;
    }

    if (!t)
    {
        if (!e && s && s->errors)
        {   // if there was an error evaluating the symbol, it might actually
            // be a type. Avoid misleading error messages.
            error(loc, "%s had previous errors", toChars());
        }
        else
            error(loc, "%s is used as a type", toChars());
        t = terror;
    }
    return t;
}

Dsymbol *TypeInstance::toDsymbol(Scope *sc)
{
    Type *t;
    Expression *e;
    Dsymbol *s;

    //printf("TypeInstance::semantic(%s)\n", toChars());
    resolve(loc, sc, &e, &t, &s);

    return s;
}

Type *TypeInstance::reliesOnTident(TemplateParameters *tparams)
{
    if (tparams)
    {
        for (size_t i = 0; i < tparams->dim; i++)
        {
            TemplateParameter *tp = (*tparams)[i];
            if (tempinst->name == tp->ident)
                return this;
        }
        if (!tempinst->tiargs)
            return NULL;
        for (size_t i = 0; i < tempinst->tiargs->dim; i++)
        {
            Type *t = isType((*tempinst->tiargs)[i]);
            t = t ? t->reliesOnTident(tparams) : NULL;
            if (t)
                return t;
        }
        return NULL;
    }
    else
    {
        return Type::reliesOnTident(tparams);
    }
}

Expression *TypeInstance::toExpression()
{
    return new ScopeExp(loc, tempinst);
}


/***************************** TypeTypeof *****************************/

TypeTypeof::TypeTypeof(Loc loc, Expression *exp)
        : TypeQualified(Ttypeof, loc)
{
    this->exp = exp;
    inuse = 0;
}

const char *TypeTypeof::kind()
{
    return "typeof";
}

Type *TypeTypeof::syntaxCopy()
{
    //printf("TypeTypeof::syntaxCopy() %s\n", toChars());
    TypeTypeof *t;

    t = new TypeTypeof(loc, exp->syntaxCopy());
    t->syntaxCopyHelper(this);
    t->mod = mod;
    return t;
}

Dsymbol *TypeTypeof::toDsymbol(Scope *sc)
{
    Type *t;

    t = semantic(loc, sc);
    if (t == this)
        return NULL;
    return t->toDsymbol(sc);
}

void TypeTypeof::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    buf->writestring("typeof(");
    exp->toCBuffer(buf, hgs);
    buf->writeByte(')');
    toCBuffer2Helper(buf, hgs);
}

void TypeTypeof::resolve(Loc loc, Scope *sc, Expression **pe, Type **pt, Dsymbol **ps)
{
    *pe = NULL;
    *pt = NULL;
    *ps = NULL;

    //printf("TypeTypeof::resolve(sc = %p, idents = '%s')\n", sc, toChars());
    //static int nest; if (++nest == 50) *(char*)0=0;
    if (inuse)
    {
        inuse = 2;
        error(loc, "circular typeof definition");
        goto Lerr;
    }
    inuse++;

    Type *t;
    {
        Scope *sc2 = sc->push();
        sc2->intypeof = 1;
        sc2->speculative = true;
        sc2->flags |= sc->flags & SCOPEstaticif;
        unsigned oldspecgag = global.speculativeGag;
        if (global.gag)
            global.speculativeGag = global.gag;
        exp = exp->semantic(sc2);
        global.speculativeGag = oldspecgag;

#if DMDV2
        if (exp->type && exp->type->ty == Tfunction &&
            ((TypeFunction *)exp->type)->isproperty)
            exp = resolveProperties(sc2, exp);
#endif
        sc2->pop();
        if (exp->op == TOKtype)
        {
            error(loc, "argument %s to typeof is not an expression", exp->toChars());
            goto Lerr;
        }
        t = exp->type;
        if (!t)
        {
            error(loc, "expression (%s) has no type", exp->toChars());
            goto Lerr;
        }
        if (t->ty == Ttypeof)
        {   error(loc, "forward reference to %s", toChars());
            goto Lerr;
        }
    }
    if (idents.dim == 0)
        *pt = t;
    else
    {
        if (Dsymbol *s = t->toDsymbol(sc))
            resolveHelper(loc, sc, s, NULL, pe, pt, ps);
        else
        {
            Expression *e = new TypeExp(loc, t);
            for (size_t i = 0; i < idents.dim; i++)
            {
                RootObject *id = idents[i];
                switch (id->dyncast())
                {
                    case DYNCAST_IDENTIFIER:
                        e = new DotIdExp(loc, e, (Identifier *)id);
                        break;
                    case DYNCAST_DSYMBOL:
                    {
                        TemplateInstance *ti = ((Dsymbol *)id)->isTemplateInstance();
                        e = new DotExp(loc, e, new ScopeExp(loc, ti));
                        break;
                    }
                    default:
                        assert(0);
                }
            }
            e = e->semantic(sc);
            if ((*ps = getDsymbol(e)) == NULL)
            {
                if (e->op == TOKtype)
                    *pt = e->type;
                else
                    *pe = e;
            }
        }
    }
    if (*pt)
        (*pt) = (*pt)->addMod(mod);
    inuse--;
    return;

Lerr:
    *pt = Type::terror;
    inuse--;
    return;
}

Type *TypeTypeof::semantic(Loc loc, Scope *sc)
{
    //printf("TypeTypeof::semantic() %s\n", toChars());

    Expression *e;
    Type *t;
    Dsymbol *s;
    resolve(loc, sc, &e, &t, &s);
    if (s && (t = s->getType()) != NULL)
        t = t->addMod(mod);
    if (!t)
    {
        error(loc, "%s is used as a type", toChars());
        t = Type::terror;
    }
    return t;
}

d_uns64 TypeTypeof::size(Loc loc)
{
    if (exp->type)
        return exp->type->size(loc);
    else
        return TypeQualified::size(loc);
}



/***************************** TypeReturn *****************************/

TypeReturn::TypeReturn(Loc loc)
        : TypeQualified(Treturn, loc)
{
}

const char *TypeReturn::kind()
{
    return "return";
}

Type *TypeReturn::syntaxCopy()
{
    TypeReturn *t = new TypeReturn(loc);
    t->syntaxCopyHelper(this);
    t->mod = mod;
    return t;
}

Dsymbol *TypeReturn::toDsymbol(Scope *sc)
{
    Type *t = semantic(Loc(), sc);
    if (t == this)
        return NULL;
    return t->toDsymbol(sc);
}

void TypeReturn::resolve(Loc loc, Scope *sc, Expression **pe, Type **pt, Dsymbol **ps)
{
    *pe = NULL;
    *pt = NULL;
    *ps = NULL;

    //printf("TypeReturn::resolve(sc = %p, idents = '%s')\n", sc, toChars());
    Type *t;
    {
        FuncDeclaration *func = sc->func;
        if (!func)
        {   error(loc, "typeof(return) must be inside function");
            goto Lerr;
        }
        if (func->fes)
            func = func->fes->func;

        t = func->type->nextOf();
        if (!t)
        {
            error(loc, "cannot use typeof(return) inside function %s with inferred return type", sc->func->toChars());
            goto Lerr;
        }
    }
    if (idents.dim == 0)
        *pt = t;
    else
    {
        if (Dsymbol *s = t->toDsymbol(sc))
            resolveHelper(loc, sc, s, NULL, pe, pt, ps);
        else
        {
            Expression *e = new TypeExp(loc, t);
            for (size_t i = 0; i < idents.dim; i++)
            {
                RootObject *id = idents[i];
                switch (id->dyncast())
                {
                    case DYNCAST_IDENTIFIER:
                        e = new DotIdExp(loc, e, (Identifier *)id);
                        break;
                    case DYNCAST_DSYMBOL:
                    {
                        TemplateInstance *ti = ((Dsymbol *)id)->isTemplateInstance();
                        e = new DotExp(loc, e, new ScopeExp(loc, ti));
                        break;
                    }
                    default:
                        assert(0);
                }
            }
            e = e->semantic(sc);
            if ((*ps = getDsymbol(e)) == NULL)
            {
                if (e->op == TOKtype)
                    *pt = e->type;
                else
                    *pe = e;
            }
        }
    }
    if (*pt)
        (*pt) = (*pt)->addMod(mod);
    return;

Lerr:
    *pt = Type::terror;
    return;
}

Type *TypeReturn::semantic(Loc loc, Scope *sc)
{
    //printf("TypeReturn::semantic() %s\n", toChars());

    Expression *e;
    Type *t;
    Dsymbol *s;
    resolve(loc, sc, &e, &t, &s);
    if (s && (t = s->getType()) != NULL)
        t = t->addMod(mod);
    if (!t)
    {
        error(loc, "%s is used as a type", toChars());
        t = Type::terror;
    }
    return t;
}

void TypeReturn::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    buf->writestring("typeof(return)");
    toCBuffer2Helper(buf, hgs);
}


/***************************** TypeEnum *****************************/

TypeEnum::TypeEnum(EnumDeclaration *sym)
        : Type(Tenum)
{
    this->sym = sym;
}

const char *TypeEnum::kind()
{
    return "enum";
}

char *TypeEnum::toChars()
{
    if (mod)
        return Type::toChars();
    return sym->toChars();
}

Type *TypeEnum::syntaxCopy()
{
    return this;
}

Type *TypeEnum::semantic(Loc loc, Scope *sc)
{
    //printf("TypeEnum::semantic() %s\n", toChars());
    //sym->semantic(sc);
    return merge();
}

d_uns64 TypeEnum::size(Loc loc)
{
    if (!sym->memtype)
    {
        error(loc, "enum %s is forward referenced", sym->toChars());
        return SIZE_INVALID;
    }
    return sym->memtype->size(loc);
}

unsigned TypeEnum::alignsize()
{
    if (!sym->memtype)
    {
        error(Loc(), "enum %s is forward referenced", sym->toChars());
        return 4;
    }
    return sym->memtype->alignsize();
}

Dsymbol *TypeEnum::toDsymbol(Scope *sc)
{
    return sym;
}

Type *TypeEnum::toBasetype()
{
    if (sym->scope)
    {   // Enum is forward referenced. We don't need to resolve the whole thing,
        // just the base type
        if (sym->memtype)
        {   sym->memtype = sym->memtype->semantic(sym->loc, sym->scope);
        }
        else
        {   if (!sym->isAnonymous())
                sym->memtype = Type::tint32;
        }
    }
    if (!sym->memtype)
    {
        error(sym->loc, "enum %s is forward referenced", sym->toChars());
        return Type::terror;
    }
    return sym->memtype->toBasetype();
}

void TypeEnum::toDecoBuffer(OutBuffer *buf, int flag)
{
    const char *name = sym->mangle();
    Type::toDecoBuffer(buf, flag);
    buf->printf("%s", name);
}

void TypeEnum::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    buf->writestring(sym->toChars());
}

Expression *TypeEnum::dotExp(Scope *sc, Expression *e, Identifier *ident, int flag)
{
#if LOGDOTEXP
    printf("TypeEnum::dotExp(e = '%s', ident = '%s') '%s'\n", e->toChars(), ident->toChars(), toChars());
#endif
    Dsymbol *s = sym->search(e->loc, ident, 0);
    if (!s)
    {
        if (ident == Id::max ||
            ident == Id::min ||
            ident == Id::init ||
            ident == Id::mangleof ||
            !sym->memtype
           )
        {
            return getProperty(e->loc, ident, flag);
        }
        return sym->memtype->dotExp(sc, e, ident, flag);
    }
    EnumMember *m = s->isEnumMember();
    return m->getVarExp(e->loc, sc);
}

Expression *TypeEnum::getProperty(Loc loc, Identifier *ident, int flag)
{   Expression *e;

    if (ident == Id::max)
    {
        if (!sym->maxval)
            goto Lfwd;
        e = sym->maxval;
    }
    else if (ident == Id::min)
    {
        if (!sym->minval)
            goto Lfwd;
        e = sym->minval;
    }
    else if (ident == Id::init)
    {
        e = defaultInitLiteral(loc);
    }
    else if (ident == Id::stringof)
    {   char *s = toChars();
        e = new StringExp(loc, s, strlen(s), 'c');
        Scope sc;
        e = e->semantic(&sc);
    }
    else if (ident == Id::mangleof)
    {
        e = Type::getProperty(loc, ident, flag);
    }
    else
    {
        e = toBasetype()->getProperty(loc, ident, flag);
    }
    return e;

Lfwd:
    error(loc, "forward reference of %s.%s", toChars(), ident->toChars());
    return new ErrorExp();
}

int TypeEnum::isintegral()
{
    return sym->memtype->isintegral();
}

int TypeEnum::isfloating()
{
    return sym->memtype->isfloating();
}

int TypeEnum::isreal()
{
    return sym->memtype->isreal();
}

int TypeEnum::isimaginary()
{
    return sym->memtype->isimaginary();
}

int TypeEnum::iscomplex()
{
    return sym->memtype->iscomplex();
}

int TypeEnum::isunsigned()
{
    return sym->memtype->isunsigned();
}

int TypeEnum::isscalar()
{
    return sym->memtype->isscalar();
}

int TypeEnum::isString()
{
    return sym->memtype->isString();
}

int TypeEnum::isAssignable()
{
    return sym->memtype->isAssignable();
}

int TypeEnum::checkBoolean()
{
    return sym->memtype->checkBoolean();
}

int TypeEnum::needsDestruction()
{
    return sym->memtype->needsDestruction();
}

bool TypeEnum::needsNested()
{
    return sym->memtype ? sym->memtype->needsNested() : false;
}

MATCH TypeEnum::implicitConvTo(Type *to)
{   MATCH m;

    //printf("TypeEnum::implicitConvTo()\n");
    if (ty == to->ty && sym == ((TypeEnum *)to)->sym)
        m = (mod == to->mod) ? MATCHexact : MATCHconst;
    else if (sym->memtype->implicitConvTo(to))
        m = MATCHconvert;       // match with conversions
    else
        m = MATCHnomatch;       // no match
    return m;
}

MATCH TypeEnum::constConv(Type *to)
{
    if (equals(to))
        return MATCHexact;
    if (ty == to->ty && sym == ((TypeEnum *)to)->sym &&
        MODimplicitConv(mod, to->mod))
        return MATCHconst;
    return MATCHnomatch;
}


Expression *TypeEnum::defaultInit(Loc loc)
{
#if LOGDEFAULTINIT
    printf("TypeEnum::defaultInit() '%s'\n", toChars());
#endif
    // Initialize to first member of enum
    //printf("%s\n", sym->defaultval->type->toChars());
    if (!sym->defaultval)
    {
        error(loc, "forward reference of %s.init", toChars());
        return new ErrorExp();
    }
    Expression *e = sym->defaultval;
    e = e->copy();
    e->type = this;
    return e;
}

int TypeEnum::isZeroInit(Loc loc)
{
    if (!sym->defaultval && sym->scope)
    {   // Enum is forward referenced. We need to resolve the whole thing.
        sym->semantic(NULL);
    }
    if (!sym->defaultval)
    {
        error(loc, "enum %s is forward referenced", sym->toChars());
        return 0;
    }
    return sym->defaultval->isBool(FALSE);
}

int TypeEnum::hasPointers()
{
    return toBasetype()->hasPointers();
}

Type *TypeEnum::nextOf()
{
    assert(sym->memtype);
    return sym->memtype->nextOf();
}

/***************************** TypeTypedef *****************************/

TypeTypedef::TypeTypedef(TypedefDeclaration *sym)
        : Type(Ttypedef)
{
    this->sym = sym;
}

const char *TypeTypedef::kind()
{
    return "typedef";
}

Type *TypeTypedef::syntaxCopy()
{
    return this;
}

char *TypeTypedef::toChars()
{
    return Type::toChars();
}

Type *TypeTypedef::semantic(Loc loc, Scope *sc)
{
    //printf("TypeTypedef::semantic(%s), sem = %d\n", toChars(), sym->sem);
    int errors = global.errors;
    sym->semantic(sc);
    if (errors != global.errors || sym->errors || sym->basetype->ty == Terror)
        return terror;
    return merge();
}

d_uns64 TypeTypedef::size(Loc loc)
{
    return sym->basetype->size(loc);
}

unsigned TypeTypedef::alignsize()
{
    return sym->basetype->alignsize();
}

Dsymbol *TypeTypedef::toDsymbol(Scope *sc)
{
    return sym;
}

void TypeTypedef::toDecoBuffer(OutBuffer *buf, int flag)
{
    Type::toDecoBuffer(buf, flag);
    const char *name = sym->mangle();
    buf->printf("%s", name);
}

void TypeTypedef::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    //printf("TypeTypedef::toCBuffer2() '%s'\n", sym->toChars());
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    buf->writestring(sym->toChars());
}

Expression *TypeTypedef::dotExp(Scope *sc, Expression *e, Identifier *ident, int flag)
{
#if LOGDOTEXP
    printf("TypeTypedef::dotExp(e = '%s', ident = '%s') '%s'\n", e->toChars(), ident->toChars(), toChars());
#endif
    if (ident == Id::init)
    {
        return Type::dotExp(sc, e, ident, flag);
    }
    return sym->basetype->dotExp(sc, e, ident, flag);
}

structalign_t TypeTypedef::alignment()
{
    if (sym->inuse)
    {
        sym->error("circular definition");
        sym->basetype = Type::terror;
        return STRUCTALIGN_DEFAULT;
    }
    sym->inuse = 1;
    structalign_t a = sym->basetype->alignment();
    sym->inuse = 0;
    return a;
}

Expression *TypeTypedef::getProperty(Loc loc, Identifier *ident, int flag)
{
#if LOGDOTEXP
    printf("TypeTypedef::getProperty(ident = '%s') '%s'\n", ident->toChars(), toChars());
#endif
    if (ident == Id::init)
    {
        return Type::getProperty(loc, ident, flag);
    }
    return sym->basetype->getProperty(loc, ident, flag);
}

int TypeTypedef::isintegral()
{
    //printf("TypeTypedef::isintegral()\n");
    //printf("sym = '%s'\n", sym->toChars());
    //printf("basetype = '%s'\n", sym->basetype->toChars());
    return sym->basetype->isintegral();
}

int TypeTypedef::isfloating()
{
    return sym->basetype->isfloating();
}

int TypeTypedef::isreal()
{
    return sym->basetype->isreal();
}

int TypeTypedef::isimaginary()
{
    return sym->basetype->isimaginary();
}

int TypeTypedef::iscomplex()
{
    return sym->basetype->iscomplex();
}

int TypeTypedef::isunsigned()
{
    return sym->basetype->isunsigned();
}

int TypeTypedef::isscalar()
{
    return sym->basetype->isscalar();
}

int TypeTypedef::isAssignable()
{
    return sym->basetype->isAssignable();
}

int TypeTypedef::checkBoolean()
{
    return sym->basetype->checkBoolean();
}

int TypeTypedef::needsDestruction()
{
    return sym->basetype->needsDestruction();
}

bool TypeTypedef::needsNested()
{
    return sym->basetype->needsNested();
}

Type *TypeTypedef::toBasetype()
{
    if (sym->inuse)
    {
        sym->error("circular definition");
        sym->basetype = Type::terror;
        return Type::terror;
    }
    sym->inuse = 1;
    Type *t = sym->basetype->toBasetype();
    sym->inuse = 0;
    t = t->addMod(mod);
    return t;
}

MATCH TypeTypedef::implicitConvTo(Type *to)
{   MATCH m;

    //printf("TypeTypedef::implicitConvTo(to = %s) %s\n", to->toChars(), toChars());
    if (equals(to))
        m = MATCHexact;         // exact match
    else if (sym->basetype->implicitConvTo(to))
        m = MATCHconvert;       // match with conversions
    else if (ty == to->ty && sym == ((TypeTypedef *)to)->sym)
    {
        m = constConv(to);
    }
    else
        m = MATCHnomatch;       // no match
    return m;
}

MATCH TypeTypedef::constConv(Type *to)
{
    if (equals(to))
        return MATCHexact;
    if (ty == to->ty && sym == ((TypeTypedef *)to)->sym)
        return sym->basetype->implicitConvTo(((TypeTypedef *)to)->sym->basetype);
    return MATCHnomatch;
}

Type *TypeTypedef::toHeadMutable()
{
    if (!mod)
        return this;

    Type *tb = toBasetype();
    Type *t = tb->toHeadMutable();
    if (t->equals(tb))
        return this;
    else
        return mutableOf();
}

Expression *TypeTypedef::defaultInit(Loc loc)
{
#if LOGDEFAULTINIT
    printf("TypeTypedef::defaultInit() '%s'\n", toChars());
#endif
    if (sym->init)
    {
        //sym->init->toExpression()->print();
        return sym->init->toExpression();
    }
    Type *bt = sym->basetype;
    Expression *e = bt->defaultInit(loc);
    e->type = this;
    while (bt->ty == Tsarray)
    {   TypeSArray *tsa = (TypeSArray *)bt;
        e->type = tsa->next;
        bt = tsa->next->toBasetype();
    }
    return e;
}

Expression *TypeTypedef::defaultInitLiteral(Loc loc)
{
#if LOGDEFAULTINIT
    printf("TypeTypedef::defaultInitLiteral() '%s'\n", toChars());
#endif
    if (sym->init)
    {
        //sym->init->toExpression()->print();
        return sym->init->toExpression();
    }
    Type *bt = sym->basetype;
    Expression *e = bt->defaultInitLiteral(loc);
    e->type = this;
    return e;
}

int TypeTypedef::isZeroInit(Loc loc)
{
    if (sym->init)
    {
        if (sym->init->isVoidInitializer())
            return 1;           // initialize voids to 0
        Expression *e = sym->init->toExpression();
        if (e && e->isBool(FALSE))
            return 1;
        return 0;               // assume not
    }
    if (sym->inuse)
    {
        sym->error("circular definition");
        sym->basetype = Type::terror;
    }
    sym->inuse = 1;
    int result = sym->basetype->isZeroInit(loc);
    sym->inuse = 0;
    return result;
}

int TypeTypedef::hasPointers()
{
    return toBasetype()->hasPointers();
}

int TypeTypedef::hasWild()
{
    assert(toBasetype());
    return mod & MODwild || toBasetype()->hasWild();
}

/***************************** TypeStruct *****************************/

TypeStruct::TypeStruct(StructDeclaration *sym)
        : Type(Tstruct)
{
    this->sym = sym;
    this->att = RECfwdref;
}

const char *TypeStruct::kind()
{
    return "struct";
}

char *TypeStruct::toChars()
{
    //printf("sym.parent: %s, deco = %s\n", sym->parent->toChars(), deco);
    if (mod)
        return Type::toChars();
    TemplateInstance *ti = sym->parent->isTemplateInstance();
    if (ti && ti->toAlias() == sym)
    {
        return ti->toChars();
    }
    return sym->toChars();
}

Type *TypeStruct::syntaxCopy()
{
    return this;
}

Type *TypeStruct::semantic(Loc loc, Scope *sc)
{
    //printf("TypeStruct::semantic('%s')\n", sym->toChars());

    /* Cannot do semantic for sym because scope chain may not
     * be right.
     */
    //sym->semantic(sc);

    return merge();
}

d_uns64 TypeStruct::size(Loc loc)
{
    return sym->size(loc);
}

unsigned TypeStruct::alignsize()
{
    sym->size(Loc());               // give error for forward references
    return sym->alignsize;
}

Dsymbol *TypeStruct::toDsymbol(Scope *sc)
{
    return sym;
}

void TypeStruct::toDecoBuffer(OutBuffer *buf, int flag)
{
    const char *name = sym->mangle();
    //printf("TypeStruct::toDecoBuffer('%s') = '%s'\n", toChars(), name);
    Type::toDecoBuffer(buf, flag);
    buf->printf("%s", name);
}

void TypeStruct::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    TemplateInstance *ti = sym->parent->isTemplateInstance();
    if (ti && ti->toAlias() == sym)
        buf->writestring(ti->toChars());
    else
        buf->writestring(sym->toChars());
}

Expression *TypeStruct::dotExp(Scope *sc, Expression *e, Identifier *ident, int flag)
{
    VarDeclaration *v;
    Dsymbol *s;
    DotVarExp *de;

#if LOGDOTEXP
    printf("TypeStruct::dotExp(e = '%s', ident = '%s')\n", e->toChars(), ident->toChars());
#endif
    if (!sym->members)
    {
        error(e->loc, "struct %s is forward referenced", sym->toChars());
        return new ErrorExp();
    }

    /* If e.tupleof
     */
    if (ident == Id::tupleof)
    {
        /* Create a TupleExp out of the fields of the struct e:
         * (e.field0, e.field1, e.field2, ...)
         */
        e = e->semantic(sc);    // do this before turning on noaccesscheck
        e->type->size();        // do semantic of type
        Expressions *exps = new Expressions;
        exps->reserve(sym->fields.dim);

        Expression *e0 = NULL;
        Expression *ev = e;
        if (sc->func && e->hasSideEffect())
        {
            Identifier *id = Lexer::uniqueId("__tup");
            ExpInitializer *ei = new ExpInitializer(e->loc, e);
            VarDeclaration *vd = new VarDeclaration(e->loc, NULL, id, ei);
            vd->storage_class |= STCctfe | STCref | STCforeach;

            e0 = new DeclarationExp(e->loc, vd);
            ev = new VarExp(e->loc, vd);
        }
        for (size_t i = 0; i < sym->fields.dim; i++)
        {
            VarDeclaration *v = sym->fields[i];
            exps->push(new DotVarExp(ev->loc, ev, v));
        }
        e = new TupleExp(e->loc, e0, exps);
        sc = sc->push();
        sc->noaccesscheck = 1;
        e = e->semantic(sc);
        sc->pop();
        return e;
    }

    if (e->op == TOKdotexp)
    {   DotExp *de = (DotExp *)e;

        if (de->e1->op == TOKimport)
        {
            assert(0);  // cannot find a case where this happens; leave
                        // assert in until we do
            ScopeExp *se = (ScopeExp *)de->e1;

            s = se->sds->search(e->loc, ident, 0);
            e = de->e1;
            goto L1;
        }
    }

    s = sym->search(e->loc, ident, 0);
L1:
    if (!s)
    {
        if (sym->scope)                 // it's a fwd ref, maybe we can resolve it
        {
            sym->semantic(NULL);
            s = sym->search(e->loc, ident, 0);
        }
        if (!s)
            return noMember(sc, e, ident, flag);
    }
    if (!s->isFuncDeclaration())        // because of overloading
        s->checkDeprecated(e->loc, sc);
    s = s->toAlias();

    v = s->isVarDeclaration();
    if (v && v->inuse && (!v->type || !v->type->deco))  // Bugzilla 9494
    {   e->error("circular reference to '%s'", v->toPrettyChars());
        return new ErrorExp();
    }
    if (v && !v->isDataseg() && (v->storage_class & STCmanifest))
    {
        Expression *ve = new VarExp(e->loc, v);
        ve = ve->semantic(sc);
        return ve;
    }

    if (s->getType())
    {
        return new TypeExp(e->loc, s->getType());
    }

    EnumMember *em = s->isEnumMember();
    if (em)
    {
        return em->getVarExp(e->loc, sc);
    }

    TemplateMixin *tm = s->isTemplateMixin();
    if (tm)
    {
        Expression *de = new DotExp(e->loc, e, new ScopeExp(e->loc, tm));
        de->type = e->type;
        return de;
    }

    TemplateDeclaration *td = s->isTemplateDeclaration();
    if (td)
    {
        if (e->op == TOKtype)
            e = new ScopeExp(e->loc, td);
        else
            e = new DotTemplateExp(e->loc, e, td);
        e = e->semantic(sc);
        return e;
    }

    TemplateInstance *ti = s->isTemplateInstance();
    if (ti)
    {   if (!ti->semanticRun)
        {
            if (global.errors)
                return new ErrorExp();  // TemplateInstance::semantic() will fail anyway
            ti->semantic(sc);
        }
        s = ti->inst->toAlias();
        if (!s->isTemplateInstance())
            goto L1;
        Expression *de = new DotExp(e->loc, e, new ScopeExp(e->loc, ti));
        de->type = e->type;
        return de;
    }

    if (s->isImport() || s->isModule() || s->isPackage())
    {
        e = new DsymbolExp(e->loc, s, 0);
        e = e->semantic(sc);
        return e;
    }

    OverloadSet *o = s->isOverloadSet();
    if (o)
    {
        OverExp *oe = new OverExp(e->loc, o);
        if (e->op == TOKtype)
            return oe;
        return new DotExp(e->loc, e, oe);
    }

    Declaration *d = s->isDeclaration();
#ifdef DEBUG
    if (!d)
        printf("d = %s '%s'\n", s->kind(), s->toChars());
#endif
    assert(d);

    if (e->op == TOKtype)
    {
        /* It's:
         *    Struct.d
         */
        if (TupleDeclaration *tup = d->isTupleDeclaration())
        {
            e = new TupleExp(e->loc, tup);
            e = e->semantic(sc);
            return e;
        }
        if (d->needThis() && sc->intypeof != 1)
        {
            /* Rewrite as:
             *  this.d
             */
            if (hasThis(sc))
            {
                e = new DotVarExp(e->loc, new ThisExp(e->loc), d);
                e = e->semantic(sc);
                return e;
            }
        }
        accessCheck(e->loc, sc, e, d);
        VarExp *ve = new VarExp(e->loc, d, 1);
        if (d->isVarDeclaration() && d->needThis())
            ve->type = d->type->addMod(e->type->mod);
        return ve;
    }

    bool unreal = e->op == TOKvar && ((VarExp *)e)->var->isField();
    if (d->isDataseg() || unreal && d->isField())
    {
        // (e, d)
        accessCheck(e->loc, sc, e, d);
        Expression *ve = new VarExp(e->loc, d);
        e = unreal ? ve : new CommaExp(e->loc, e, ve);
        e = e->semantic(sc);
        return e;
    }

    if (v)
    {
        if (v->toParent() != sym)
            sym->error(e->loc, "'%s' is not a member", v->toChars());

        // *(&e + offset)
        accessCheck(e->loc, sc, e, d);
#if 0
        Expression *b = new AddrExp(e->loc, e);
        b->type = e->type->pointerTo();
        b = new AddExp(e->loc, b, new IntegerExp(e->loc, v->offset, Type::tint32));
        b->type = v->type->pointerTo();
        b = new PtrExp(e->loc, b);
        b->type = v->type->addMod(e->type->mod);
        return b;
#endif
    }

    de = new DotVarExp(e->loc, e, d);
    return de->semantic(sc);
}

structalign_t TypeStruct::alignment()
{
    if (sym->alignment == 0)
        sym->size(Loc());
    return sym->alignment;
}

Expression *TypeStruct::defaultInit(Loc loc)
{
#if LOGDEFAULTINIT
    printf("TypeStruct::defaultInit() '%s'\n", toChars());
#endif
    Declaration *d = new SymbolDeclaration(sym->loc, sym);
    assert(d);
    d->type = this;
    return new VarExp(sym->loc, d);
}

/***************************************
 * Use when we prefer the default initializer to be a literal,
 * rather than a global immutable variable.
 */
Expression *TypeStruct::defaultInitLiteral(Loc loc)
{
#if LOGDEFAULTINIT
    printf("TypeStruct::defaultInitLiteral() '%s'\n", toChars());
#endif
    //if (sym->isNested())
    //    return defaultInit(loc);
    Expressions *structelems = new Expressions();
    structelems->setDim(sym->fields.dim - sym->isNested());
    unsigned offset = 0;
    for (size_t j = 0; j < structelems->dim; j++)
    {
        VarDeclaration *vd = sym->fields[j];
        Expression *e;
        if (vd->offset < offset)
            e = NULL;
        else if (vd->init)
        {
            if (vd->init->isVoidInitializer())
                e = NULL;
            else
                e = vd->getConstInitializer(false);
        }
        else
            e = vd->type->defaultInitLiteral(loc);
        if (e && e->op == TOKerror)
            return e;
        offset = vd->offset + vd->type->size();
        (*structelems)[j] = e;
    }
    StructLiteralExp *structinit = new StructLiteralExp(loc, (StructDeclaration *)sym, structelems);

    /* Copy from the initializer symbol for larger symbols,
     * otherwise the literals expressed as code get excessively large.
     */
    if (size(loc) > Target::ptrsize * 4 && !needsNested())
        structinit->sinit = sym->toInitializer();

    structinit->type = this;
    return structinit;
}


int TypeStruct::isZeroInit(Loc loc)
{
    return sym->zeroInit;
}

int TypeStruct::checkBoolean()
{
    return FALSE;
}

int TypeStruct::needsDestruction()
{
    return sym->dtor != NULL;
}

bool TypeStruct::needsNested()
{
    if (sym->isNested())
        return true;

    for (size_t i = 0; i < sym->fields.dim; i++)
    {
        Dsymbol *s = sym->fields[i];
        VarDeclaration *vd = s->isVarDeclaration();
        if (vd && !vd->isDataseg() && vd->type->needsNested())
            return true;
    }
    return false;
}

int TypeStruct::isAssignable()
{
    int assignable = TRUE;
    unsigned offset;

    /* If any of the fields are const or invariant,
     * then one cannot assign this struct.
     */
    for (size_t i = 0; i < sym->fields.dim; i++)
    {   VarDeclaration *v = sym->fields[i];
        //printf("%s [%d] v = (%s) %s, v->offset = %d, v->parent = %s", sym->toChars(), i, v->kind(), v->toChars(), v->offset, v->parent->kind());
        if (i == 0)
            ;
        else if (v->offset == offset)
        {
            /* If any fields of anonymous union are assignable,
             * then regard union as assignable.
             * This is to support unsafe things like Rebindable templates.
             */
            if (assignable)
                continue;
        }
        else
        {
            if (!assignable)
                return FALSE;
        }
        assignable = v->type->isMutable() && v->type->isAssignable();
        offset = v->offset;
        //printf(" -> assignable = %d\n", assignable);
    }

    return assignable;
}

int TypeStruct::hasPointers()
{
    // Probably should cache this information in sym rather than recompute
    StructDeclaration *s = sym;

    sym->size(Loc());               // give error for forward references
    for (size_t i = 0; i < s->fields.dim; i++)
    {
        Dsymbol *sm = s->fields[i];
        Declaration *d = sm->isDeclaration();
        if (d->storage_class & STCref || d->hasPointers())
            return TRUE;
    }
    return FALSE;
}

MATCH TypeStruct::implicitConvTo(Type *to)
{   MATCH m;

    //printf("TypeStruct::implicitConvTo(%s => %s)\n", toChars(), to->toChars());
    if (to->ty == Taarray && sym->ident == Id::AssociativeArray)
    {
        /* If there is an error instantiating AssociativeArray!(), it shouldn't
         * be reported -- it just means implicit conversion is impossible.
         */
        int errs = global.startGagging();
        to = ((TypeAArray*)to)->getImpl()->type;
        if (global.endGagging(errs))
        {
            return MATCHnomatch;
        }
    }

    if (ty == to->ty && sym == ((TypeStruct *)to)->sym)
    {   m = MATCHexact;         // exact match
        if (mod != to->mod)
        {
            m = MATCHconst;
            if (MODimplicitConv(mod, to->mod))
                ;
            else
            {   /* Check all the fields. If they can all be converted,
                 * allow the conversion.
                 */
                for (size_t i = 0; i < sym->fields.dim; i++)
                {   Dsymbol *s = sym->fields[i];
                    VarDeclaration *v = s->isVarDeclaration();
                    assert(v && v->isField());

                    // 'from' type
                    Type *tvf = v->type->addMod(mod);

                    // 'to' type
                    Type *tv = v->type->castMod(to->mod);

                    // field match
                    MATCH mf = tvf->implicitConvTo(tv);
                    //printf("\t%s => %s, match = %d\n", v->type->toChars(), tv->toChars(), mf);

                    if (mf == MATCHnomatch)
                        return mf;
                    if (mf < m)         // if field match is worse
                        m = mf;
                }
            }
        }
    }
    else if (sym->aliasthis && !(att & RECtracing))
    {
        att = (AliasThisRec)(att | RECtracing);
        m = aliasthisOf()->implicitConvTo(to);
        att = (AliasThisRec)(att & ~RECtracing);
    }
    else
        m = MATCHnomatch;       // no match
    return m;
}

MATCH TypeStruct::constConv(Type *to)
{
    if (equals(to))
        return MATCHexact;
    if (ty == to->ty && sym == ((TypeStruct *)to)->sym &&
        MODimplicitConv(mod, to->mod))
        return MATCHconst;
    return MATCHnomatch;
}

unsigned TypeStruct::wildConvTo(Type *tprm)
{
    if (ty == tprm->ty && sym == ((TypeStruct *)tprm)->sym)
        return Type::wildConvTo(tprm);

    unsigned mod = 0;

    if (sym->aliasthis && !(att & RECtracing))
    {
        att = (AliasThisRec)(att | RECtracing);
        mod = aliasthisOf()->wildConvTo(tprm);
        att = (AliasThisRec)(att & ~RECtracing);
    }

    return mod;
}

Type *TypeStruct::toHeadMutable()
{
    return this;
}


/***************************** TypeClass *****************************/

TypeClass::TypeClass(ClassDeclaration *sym)
        : Type(Tclass)
{
    this->sym = sym;
    this->att = RECfwdref;
}

const char *TypeClass::kind()
{
    return "class";
}

char *TypeClass::toChars()
{
    if (mod)
        return Type::toChars();
    return (char *)sym->toPrettyChars();
}

Type *TypeClass::syntaxCopy()
{
    return this;
}

Type *TypeClass::semantic(Loc loc, Scope *sc)
{
    //printf("TypeClass::semantic(%s)\n", sym->toChars());
    if (deco)
        return this;
    //printf("\t%s\n", merge()->deco);
    return merge();
}

d_uns64 TypeClass::size(Loc loc)
{
    return Target::ptrsize;
}

Dsymbol *TypeClass::toDsymbol(Scope *sc)
{
    return sym;
}

void TypeClass::toDecoBuffer(OutBuffer *buf, int flag)
{
    const char *name = sym->mangle();
    //printf("TypeClass::toDecoBuffer('%s' flag=%d mod=%x) = '%s'\n", toChars(), flag, mod, name);
    Type::toDecoBuffer(buf, flag);
    buf->printf("%s", name);
}

void TypeClass::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    buf->writestring(sym->toChars());
}

Expression *TypeClass::dotExp(Scope *sc, Expression *e, Identifier *ident, int flag)
{
    VarDeclaration *v;
    Dsymbol *s;

#if LOGDOTEXP
    printf("TypeClass::dotExp(e='%s', ident='%s')\n", e->toChars(), ident->toChars());
#endif

    if (e->op == TOKdotexp)
    {   DotExp *de = (DotExp *)e;

        if (de->e1->op == TOKimport)
        {
            ScopeExp *se = (ScopeExp *)de->e1;

            s = se->sds->search(e->loc, ident, 0);
            e = de->e1;
            goto L1;
        }
    }

    if (ident == Id::tupleof)
    {
        /* Create a TupleExp
         */
        e = e->semantic(sc);    // do this before turning on noaccesscheck

        /* If this is called in the middle of a class declaration,
         *  class Inner {
         *    int x;
         *    alias typeof(Inner.tupleof) T;
         *    int y;
         *  }
         * then Inner.y will be omitted from the tuple.
         */
        // Detect that error, and at least try to run semantic() on it if we can
        sym->size(e->loc);

        Expressions *exps = new Expressions;
        exps->reserve(sym->fields.dim);

        Expression *e0 = NULL;
        Expression *ev = e;
        if (sc->func && e->hasSideEffect())
        {
            Identifier *id = Lexer::uniqueId("__tup");
            ExpInitializer *ei = new ExpInitializer(e->loc, e);
            VarDeclaration *vd = new VarDeclaration(e->loc, NULL, id, ei);
            vd->storage_class |= STCctfe | STCref | STCforeach;

            e0 = new DeclarationExp(e->loc, vd);
            ev = new VarExp(e->loc, vd);
        }
        for (size_t i = 0; i < sym->fields.dim; i++)
        {   VarDeclaration *v = sym->fields[i];
            // Don't include hidden 'this' pointer
            if (v->isThisDeclaration())
                continue;
            exps->push(new DotVarExp(ev->loc, ev, v));
        }
        e = new TupleExp(e->loc, e0, exps);
        sc = sc->push();
        sc->noaccesscheck = 1;
        e = e->semantic(sc);
        sc->pop();
        return e;
    }

    s = sym->search(e->loc, ident, 0);
L1:
    if (!s)
    {
        // See if it's 'this' class or a base class
        if (sym->ident == ident)
        {
            if (e->op == TOKtype)
                return Type::getProperty(e->loc, ident, 0);
            return new DotTypeExp(e->loc, e, sym);
        }
        if (ClassDeclaration *cbase = sym->searchBase(e->loc, ident))
        {
            if (e->op == TOKtype)
                return Type::getProperty(e->loc, ident, 0);
            if (InterfaceDeclaration *ifbase = cbase->isInterfaceDeclaration())
                e = new CastExp(e->loc, e, ifbase->type);
            else
                e = new DotTypeExp(e->loc, e, cbase);
            return e;
        }

        if (ident == Id::classinfo)
        {
            assert(Type::typeinfoclass);
            Type *t = Type::typeinfoclass->type;
            if (e->op == TOKtype || e->op == TOKdottype)
            {
                /* For type.classinfo, we know the classinfo
                 * at compile time.
                 */
                if (!sym->vclassinfo)
                    sym->vclassinfo = new TypeInfoClassDeclaration(sym->type);
                e = new VarExp(e->loc, sym->vclassinfo);
                e = e->addressOf(sc);
                e->type = t;    // do this so we don't get redundant dereference
            }
            else
            {   /* For class objects, the classinfo reference is the first
                 * entry in the vtbl[]
                 */
                e = new PtrExp(e->loc, e);
                e->type = t->pointerTo();
                if (sym->isInterfaceDeclaration())
                {
                    if (sym->isCPPinterface())
                    {   /* C++ interface vtbl[]s are different in that the
                         * first entry is always pointer to the first virtual
                         * function, not classinfo.
                         * We can't get a .classinfo for it.
                         */
                        error(e->loc, "no .classinfo for C++ interface objects");
                    }
                    /* For an interface, the first entry in the vtbl[]
                     * is actually a pointer to an instance of struct Interface.
                     * The first member of Interface is the .classinfo,
                     * so add an extra pointer indirection.
                     */
                    e->type = e->type->pointerTo();
                    e = new PtrExp(e->loc, e);
                    e->type = t->pointerTo();
                }
                e = new PtrExp(e->loc, e, t);
            }
            return e;
        }

        if (ident == Id::__vptr)
        {   /* The pointer to the vtbl[]
             * *cast(invariant(void*)**)e
             */
            e = e->castTo(sc, tvoidptr->immutableOf()->pointerTo()->pointerTo());
            e = new PtrExp(e->loc, e);
            e = e->semantic(sc);
            return e;
        }

        if (ident == Id::__monitor)
        {   /* The handle to the monitor (call it a void*)
             * *(cast(void**)e + 1)
             */
            e = e->castTo(sc, tvoidptr->pointerTo());
            e = new AddExp(e->loc, e, new IntegerExp(1));
            e = new PtrExp(e->loc, e);
            e = e->semantic(sc);
            return e;
        }

        if (ident == Id::typeinfo)
        {
            error(e->loc, ".typeinfo deprecated, use typeid(type)");
            return getTypeInfo(sc);
        }
        if (ident == Id::outer && sym->vthis)
        {
            s = sym->vthis;
        }
        else
        {
            return noMember(sc, e, ident, flag);
        }
    }
    if (!s->isFuncDeclaration())        // because of overloading
        s->checkDeprecated(e->loc, sc);
    s = s->toAlias();

    v = s->isVarDeclaration();
    if (v && v->inuse && (!v->type || !v->type->deco))  // Bugzilla 9494
    {   e->error("circular reference to '%s'", v->toPrettyChars());
        return new ErrorExp();
    }
    if (v && !v->isDataseg() && (v->storage_class & STCmanifest))
    {
        Expression *ve = new VarExp(e->loc, v);
        ve = ve->semantic(sc);
        return ve;
    }

    if (s->getType())
    {
        return new TypeExp(e->loc, s->getType());
    }

    EnumMember *em = s->isEnumMember();
    if (em)
    {
        return em->getVarExp(e->loc, sc);
    }

    TemplateMixin *tm = s->isTemplateMixin();
    if (tm)
    {
        Expression *de = new DotExp(e->loc, e, new ScopeExp(e->loc, tm));
        de->type = e->type;
        return de;
    }

    TemplateDeclaration *td = s->isTemplateDeclaration();
    if (td)
    {
        if (e->op == TOKtype)
            e = new ScopeExp(e->loc, td);
        else
            e = new DotTemplateExp(e->loc, e, td);
        e = e->semantic(sc);
        return e;
    }

    TemplateInstance *ti = s->isTemplateInstance();
    if (ti)
    {   if (!ti->semanticRun)
        {
            if (global.errors)
                return new ErrorExp();  // TemplateInstance::semantic() will fail anyway
            ti->semantic(sc);
        }
        s = ti->inst->toAlias();
        if (!s->isTemplateInstance())
            goto L1;
        Expression *de = new DotExp(e->loc, e, new ScopeExp(e->loc, ti));
        de->type = e->type;
        return de;
    }

    if (s->isImport() || s->isModule() || s->isPackage())
    {
        e = new DsymbolExp(e->loc, s, 0);
        e = e->semantic(sc);
        return e;
    }

    OverloadSet *o = s->isOverloadSet();
    if (o)
    {
        OverExp *oe = new OverExp(e->loc, o);
        if (e->op == TOKtype)
            return oe;
        return new DotExp(e->loc, e, oe);
    }

    Declaration *d = s->isDeclaration();
    if (!d)
    {
        e->error("%s.%s is not a declaration", e->toChars(), ident->toChars());
        return new ErrorExp();
    }

    if (e->op == TOKtype)
    {
        /* It's:
         *    Class.d
         */
        if (TupleDeclaration *tup = d->isTupleDeclaration())
        {
            e = new TupleExp(e->loc, tup);
            e = e->semantic(sc);
            return e;
        }
        if (d->needThis() && sc->intypeof != 1)
        {
            /* Rewrite as:
             *  this.d
             */
            if (hasThis(sc))
            {
                // This is almost same as getRightThis() in expression.c
                Expression *e1 = new ThisExp(e->loc);
                e1 = e1->semantic(sc);
            L2:
                Type *t = e1->type->toBasetype();
                ClassDeclaration *cd = e->type->isClassHandle();
                ClassDeclaration *tcd = t->isClassHandle();
                if (cd && tcd && (tcd == cd || cd->isBaseOf(tcd, NULL)))
                {
                    e = new DotTypeExp(e1->loc, e1, cd);
                    e = new DotVarExp(e->loc, e, d);
                    e = e->semantic(sc);
                    return e;
                }
                if (tcd && tcd->isNested())
                {   /* e1 is the 'this' pointer for an inner class: tcd.
                     * Rewrite it as the 'this' pointer for the outer class.
                     */

                    e1 = new DotVarExp(e->loc, e1, tcd->vthis);
                    e1->type = tcd->vthis->type;
                    e1->type = e1->type->addMod(t->mod);
                    // Do not call checkNestedRef()
                    //e1 = e1->semantic(sc);

                    // Skip up over nested functions, and get the enclosing
                    // class type.
                    int n = 0;
                    Dsymbol *s;
                    for (s = tcd->toParent();
                         s && s->isFuncDeclaration();
                         s = s->toParent())
                    {   FuncDeclaration *f = s->isFuncDeclaration();
                        if (f->vthis)
                        {
                            //printf("rewriting e1 to %s's this\n", f->toChars());
                            n++;
                            e1 = new VarExp(e->loc, f->vthis);
                        }
                        else
                        {
                            e = new VarExp(e->loc, d, 1);
                            return e;
                        }
                    }
                    if (s && s->isClassDeclaration())
                    {   e1->type = s->isClassDeclaration()->type;
                        e1->type = e1->type->addMod(t->mod);
                        if (n > 1)
                            e1 = e1->semantic(sc);
                    }
                    else
                        e1 = e1->semantic(sc);
                    goto L2;
                }
            }
        }
        //printf("e = %s, d = %s\n", e->toChars(), d->toChars());
        accessCheck(e->loc, sc, e, d);
        VarExp *ve = new VarExp(e->loc, d, 1);
        if (d->isVarDeclaration() && d->needThis())
            ve->type = d->type->addMod(e->type->mod);
        return ve;
    }

    bool unreal = e->op == TOKvar && ((VarExp *)e)->var->isField();
    if (d->isDataseg() || unreal && d->isField())
    {
        // (e, d)
        accessCheck(e->loc, sc, e, d);
        Expression *ve = new VarExp(e->loc, d);
        e = unreal ? ve : new CommaExp(e->loc, e, ve);
        e = e->semantic(sc);
        return e;
    }

    if (d->parent && d->toParent()->isModule())
    {
        // (e, d)
        VarExp *ve = new VarExp(e->loc, d, 1);
        e = new CommaExp(e->loc, e, ve);
        e->type = d->type;
        return e;
    }

    DotVarExp *de = new DotVarExp(e->loc, e, d, d->hasOverloads());
    return de->semantic(sc);
}

ClassDeclaration *TypeClass::isClassHandle()
{
    return sym;
}

int TypeClass::isscope()
{
    return sym->isscope;
}

int TypeClass::isBaseOf(Type *t, int *poffset)
{
    if (t && t->ty == Tclass)
    {   ClassDeclaration *cd;

        cd   = ((TypeClass *)t)->sym;
        if (sym->isBaseOf(cd, poffset))
            return 1;
    }
    return 0;
}

MATCH TypeClass::implicitConvTo(Type *to)
{
    //printf("TypeClass::implicitConvTo(to = '%s') %s\n", to->toChars(), toChars());
    MATCH m = constConv(to);
    if (m != MATCHnomatch)
        return m;

    ClassDeclaration *cdto = to->isClassHandle();
    if (cdto)
    {
        if (cdto->scope)
            cdto->semantic(NULL);
        if (cdto->isBaseOf(sym, NULL) && MODimplicitConv(mod, to->mod))
        {   //printf("'to' is base\n");
            return MATCHconvert;
        }
    }

    m = MATCHnomatch;
    if (sym->aliasthis && !(att & RECtracing))
    {
        att = (AliasThisRec)(att | RECtracing);
        m = aliasthisOf()->implicitConvTo(to);
        att = (AliasThisRec)(att & ~RECtracing);
    }

    return m;
}

MATCH TypeClass::constConv(Type *to)
{
    if (equals(to))
        return MATCHexact;
    if (ty == to->ty && sym == ((TypeClass *)to)->sym &&
        MODimplicitConv(mod, to->mod))
        return MATCHconst;

    /* Conversion derived to const(base)
     */
    int offset = 0;
    if (to->isBaseOf(this, &offset) && offset == 0 && !to->isMutable() && !to->isWild())
        return MATCHconvert;

    return MATCHnomatch;
}

unsigned TypeClass::wildConvTo(Type *tprm)
{
    Type *tcprm = tprm->substWildTo(MODconst);

    if (constConv(tcprm))
        return Type::wildConvTo(tprm);

    ClassDeclaration *cdprm = tcprm->isClassHandle();
    if (cdprm && cdprm->isBaseOf(sym, NULL))
        return Type::wildConvTo(tprm);

    unsigned mod = 0;

    if (sym->aliasthis && !(att & RECtracing))
    {
        att = (AliasThisRec)(att | RECtracing);
        mod = aliasthisOf()->wildConvTo(tprm);
        att = (AliasThisRec)(att & ~RECtracing);
    }

    return mod;
}

Type *TypeClass::toHeadMutable()
{
    return this;
}

Expression *TypeClass::defaultInit(Loc loc)
{
#if LOGDEFAULTINIT
    printf("TypeClass::defaultInit() '%s'\n", toChars());
#endif
    return new NullExp(loc, this);
}

int TypeClass::isZeroInit(Loc loc)
{
    return 1;
}

int TypeClass::checkBoolean()
{
    return TRUE;
}

int TypeClass::hasPointers()
{
    return TRUE;
}

/***************************** TypeTuple *****************************/

TypeTuple::TypeTuple(Parameters *arguments)
    : Type(Ttuple)
{
    //printf("TypeTuple(this = %p)\n", this);
    this->arguments = arguments;
    //printf("TypeTuple() %p, %s\n", this, toChars());
#ifdef DEBUG
    if (arguments)
    {
        for (size_t i = 0; i < arguments->dim; i++)
        {
            Parameter *arg = (*arguments)[i];
            assert(arg && arg->type);
        }
    }
#endif
}

/****************
 * Form TypeTuple from the types of the expressions.
 * Assume exps[] is already tuple expanded.
 */

TypeTuple::TypeTuple(Expressions *exps)
    : Type(Ttuple)
{
    Parameters *arguments = new Parameters;
    if (exps)
    {
        arguments->setDim(exps->dim);
        for (size_t i = 0; i < exps->dim; i++)
        {   Expression *e = (*exps)[i];
            if (e->type->ty == Ttuple)
                e->error("cannot form tuple of tuples");
            Parameter *arg = new Parameter(STCundefined, e->type, NULL, NULL);
            (*arguments)[i] = arg;
        }
    }
    this->arguments = arguments;
    //printf("TypeTuple() %p, %s\n", this, toChars());
}

/*******************************************
 * Type tuple with 0, 1 or 2 types in it.
 */
TypeTuple::TypeTuple()
    : Type(Ttuple)
{
    arguments = new Parameters();
}

TypeTuple::TypeTuple(Type *t1)
    : Type(Ttuple)
{
    arguments = new Parameters();
    arguments->push(new Parameter(0, t1, NULL, NULL));
}

TypeTuple::TypeTuple(Type *t1, Type *t2)
    : Type(Ttuple)
{
    arguments = new Parameters();
    arguments->push(new Parameter(0, t1, NULL, NULL));
    arguments->push(new Parameter(0, t2, NULL, NULL));
}

const char *TypeTuple::kind()
{
    return "tuple";
}

Type *TypeTuple::syntaxCopy()
{
    Parameters *args = Parameter::arraySyntaxCopy(arguments);
    Type *t = new TypeTuple(args);
    t->mod = mod;
    return t;
}

Type *TypeTuple::semantic(Loc loc, Scope *sc)
{
    //printf("TypeTuple::semantic(this = %p)\n", this);
    //printf("TypeTuple::semantic() %p, %s\n", this, toChars());
    if (!deco)
        deco = merge()->deco;

    /* Don't return merge(), because a tuple with one type has the
     * same deco as that type.
     */
    return this;
}

bool TypeTuple::equals(RootObject *o)
{
    Type *t = (Type *)o;
    //printf("TypeTuple::equals(%s, %s)\n", toChars(), t->toChars());
    if (this == t)
        return true;
    if (t->ty == Ttuple)
    {
        TypeTuple *tt = (TypeTuple *)t;
        if (arguments->dim == tt->arguments->dim)
        {
            for (size_t i = 0; i < tt->arguments->dim; i++)
            {
                Parameter *arg1 = (*arguments)[i];
                Parameter *arg2 = (*tt->arguments)[i];
                if (!arg1->type->equals(arg2->type))
                    return false;
            }
            return true;
        }
    }
    return false;
}

Type *TypeTuple::reliesOnTident(TemplateParameters *tparams)
{
    if (arguments)
    {
        for (size_t i = 0; i < arguments->dim; i++)
        {
            Parameter *arg = (*arguments)[i];
            Type *t = arg->type->reliesOnTident(tparams);
            if (t)
                return t;
        }
    }
    return NULL;
}

#if 0
Type *TypeTuple::makeConst()
{
    //printf("TypeTuple::makeConst() %s\n", toChars());
    if (cto)
        return cto;
    TypeTuple *t = (TypeTuple *)Type::makeConst();
    t->arguments = new Parameters();
    t->arguments->setDim(arguments->dim);
    for (size_t i = 0; i < arguments->dim; i++)
    {   Parameter *arg = (*arguments)[i];
        Parameter *narg = new Parameter(arg->storageClass, arg->type->constOf(), arg->ident, arg->defaultArg);
        (*t->arguments)[i] = (Parameter *)narg;
    }
    return t;
}
#endif

void TypeTuple::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    Parameter::argsToCBuffer(buf, hgs, arguments, 0);
}

void TypeTuple::toDecoBuffer(OutBuffer *buf, int flag)
{
    //printf("TypeTuple::toDecoBuffer() this = %p, %s\n", this, toChars());
    Type::toDecoBuffer(buf, flag);
    OutBuffer buf2;
    buf2.reserve(32);
    Parameter::argsToDecoBuffer(&buf2, arguments);
    int len = (int)buf2.offset;
    buf->printf("%d%.*s", len, len, (char *)buf2.extractData());
}

Expression *TypeTuple::getProperty(Loc loc, Identifier *ident, int flag)
{   Expression *e;

#if LOGDOTEXP
    printf("TypeTuple::getProperty(type = '%s', ident = '%s')\n", toChars(), ident->toChars());
#endif
    if (ident == Id::length)
    {
        e = new IntegerExp(loc, arguments->dim, Type::tsize_t);
    }
    else if (ident == Id::init)
    {
        e = defaultInitLiteral(loc);
    }
    else if (flag)
    {
        e = NULL;
    }
    else
    {
        error(loc, "no property '%s' for tuple '%s'", ident->toChars(), toChars());
        e = new ErrorExp();
    }
    return e;
}

Expression *TypeTuple::defaultInit(Loc loc)
{
    Expressions *exps = new Expressions();
    exps->setDim(arguments->dim);
    for (size_t i = 0; i < arguments->dim; i++)
    {
        Parameter *p = (*arguments)[i];
        assert(p->type);
        Expression *e = p->type->defaultInitLiteral(loc);
        if (e->op == TOKerror)
            return e;
        (*exps)[i] = e;
    }
    return new TupleExp(loc, exps);
}

/***************************** TypeSlice *****************************/

/* This is so we can slice a TypeTuple */

TypeSlice::TypeSlice(Type *next, Expression *lwr, Expression *upr)
    : TypeNext(Tslice, next)
{
    //printf("TypeSlice[%s .. %s]\n", lwr->toChars(), upr->toChars());
    this->lwr = lwr;
    this->upr = upr;
}

const char *TypeSlice::kind()
{
    return "slice";
}

Type *TypeSlice::syntaxCopy()
{
    Type *t = new TypeSlice(next->syntaxCopy(), lwr->syntaxCopy(), upr->syntaxCopy());
    t->mod = mod;
    return t;
}

Type *TypeSlice::semantic(Loc loc, Scope *sc)
{
    //printf("TypeSlice::semantic() %s\n", toChars());
    next = next->semantic(loc, sc);
    transitive();
    //printf("next: %s\n", next->toChars());

    Type *tbn = next->toBasetype();
    if (tbn->ty != Ttuple)
    {   error(loc, "can only slice tuple types, not %s", tbn->toChars());
        return Type::terror;
    }
    TypeTuple *tt = (TypeTuple *)tbn;

    lwr = semanticLength(sc, tbn, lwr);
    lwr = lwr->ctfeInterpret();
    uinteger_t i1 = lwr->toUInteger();

    upr = semanticLength(sc, tbn, upr);
    upr = upr->ctfeInterpret();
    uinteger_t i2 = upr->toUInteger();

    if (!(i1 <= i2 && i2 <= tt->arguments->dim))
    {   error(loc, "slice [%llu..%llu] is out of range of [0..%u]", i1, i2, tt->arguments->dim);
        return Type::terror;
    }

    Parameters *args = new Parameters;
    args->reserve(i2 - i1);
    for (size_t i = i1; i < i2; i++)
    {   Parameter *arg = (*tt->arguments)[i];
        args->push(arg);
    }

    Type *t = (new TypeTuple(args))->semantic(loc, sc);
    return t;
}

void TypeSlice::resolve(Loc loc, Scope *sc, Expression **pe, Type **pt, Dsymbol **ps)
{
    next->resolve(loc, sc, pe, pt, ps);
    if (*pe)
    {   // It's really a slice expression
        if (Dsymbol *s = getDsymbol(*pe))
            *pe = new DsymbolExp(loc, s, 1);
        *pe = new SliceExp(loc, *pe, lwr, upr);
    }
    else if (*ps)
    {   Dsymbol *s = *ps;
        TupleDeclaration *td = s->isTupleDeclaration();
        if (td)
        {
            /* It's a slice of a TupleDeclaration
             */
            ScopeDsymbol *sym = new ArrayScopeSymbol(sc, td);
            sym->parent = sc->scopesym;
            sc = sc->push(sym);

            lwr = lwr->ctfeSemantic(sc);
            lwr = lwr->ctfeInterpret();
            uinteger_t i1 = lwr->toUInteger();

            upr = upr->ctfeSemantic(sc);
            upr = upr->ctfeInterpret();
            uinteger_t i2 = upr->toUInteger();

            sc = sc->pop();

            if (!(i1 <= i2 && i2 <= td->objects->dim))
            {   error(loc, "slice [%llu..%llu] is out of range of [0..%u]", i1, i2, td->objects->dim);
                goto Ldefault;
            }

            if (i1 == 0 && i2 == td->objects->dim)
            {
                *ps = td;
                return;
            }

            /* Create a new TupleDeclaration which
             * is a slice [i1..i2] out of the old one.
             */
            Objects *objects = new Objects;
            objects->setDim(i2 - i1);
            for (size_t i = 0; i < objects->dim; i++)
            {
                (*objects)[i] = (*td->objects)[(size_t)i1 + i];
            }

            TupleDeclaration *tds = new TupleDeclaration(loc, td->ident, objects);
            *ps = tds;
        }
        else
            goto Ldefault;
    }
    else
    {
     Ldefault:
        Type::resolve(loc, sc, pe, pt, ps);
    }
}

void TypeSlice::toCBuffer2(OutBuffer *buf, HdrGenState *hgs, int mod)
{
    if (mod != this->mod)
    {   toCBuffer3(buf, hgs, mod);
        return;
    }
    next->toCBuffer2(buf, hgs, this->mod);

    buf->printf("[%s .. ", lwr->toChars());
    buf->printf("%s]", upr->toChars());
}

/***************************** TypeNull *****************************/

TypeNull::TypeNull()
        : Type(Tnull)
{
}

const char *TypeNull::kind()
{
    return "null";
}

Type *TypeNull::syntaxCopy()
{
    // No semantic analysis done, no need to copy
    return this;
}

MATCH TypeNull::implicitConvTo(Type *to)
{
    //printf("TypeNull::implicitConvTo(this=%p, to=%p)\n", this, to);
    //printf("from: %s\n", toChars());
    //printf("to  : %s\n", to->toChars());
    MATCH m = Type::implicitConvTo(to);
    if (m)
        return m;

    // NULL implicitly converts to any pointer type or dynamic array
    //if (type->ty == Tpointer && type->nextOf()->ty == Tvoid)
    {
        Type *tb= to->toBasetype();
        if (tb->ty == Tpointer || tb->ty == Tarray ||
            tb->ty == Taarray  || tb->ty == Tclass ||
            tb->ty == Tdelegate)
            return MATCHconst;
    }

    return MATCHnomatch;
}

int TypeNull::checkBoolean()
{
    return TRUE;
}

void TypeNull::toDecoBuffer(OutBuffer *buf, int flag)
{
    //tvoidptr->toDecoBuffer(buf, flag);
    Type::toDecoBuffer(buf, flag);
}

void TypeNull::toCBuffer(OutBuffer *buf, Identifier *ident, HdrGenState *hgs)
{
    buf->writestring("typeof(null)");
}

d_uns64 TypeNull::size(Loc loc) { return tvoidptr->size(loc); }
Expression *TypeNull::defaultInit(Loc loc) { return new NullExp(Loc(), Type::tnull); }

/***************************** Parameter *****************************/

Parameter::Parameter(StorageClass storageClass, Type *type, Identifier *ident, Expression *defaultArg)
{
    this->type = type;
    this->ident = ident;
    this->storageClass = storageClass;
    this->defaultArg = defaultArg;
}

Parameter *Parameter::syntaxCopy()
{
    Parameter *a = new Parameter(storageClass,
                type ? type->syntaxCopy() : NULL,
                ident,
                defaultArg ? defaultArg->syntaxCopy() : NULL);
    return a;
}

Parameters *Parameter::arraySyntaxCopy(Parameters *args)
{   Parameters *a = NULL;

    if (args)
    {
        a = new Parameters();
        a->setDim(args->dim);
        for (size_t i = 0; i < a->dim; i++)
        {   Parameter *arg = (*args)[i];

            arg = arg->syntaxCopy();
            (*a)[i] = arg;
        }
    }
    return a;
}

char *Parameter::argsTypesToChars(Parameters *args, int varargs)
{
    OutBuffer buf;
    buf.reserve(16);

    HdrGenState hgs;
    argsToCBuffer(&buf, &hgs, args, varargs);

    buf.writebyte(0);
    return buf.extractData();
}

void Parameter::argsToCBuffer(OutBuffer *buf, HdrGenState *hgs, Parameters *arguments, int varargs)
{
    buf->writeByte('(');
    if (arguments)
    {
        OutBuffer argbuf;
        argbuf.reserve(32);

        size_t dim = Parameter::dim(arguments);
        for (size_t i = 0; i < dim; i++)
        {
            if (i)
                buf->writestring(", ");
            Parameter *arg = Parameter::getNth(arguments, i);

            if (arg->storageClass & STCauto)
                buf->writestring("auto ");

            if (arg->storageClass & STCout)
                buf->writestring("out ");
            else if (arg->storageClass & STCref)
                buf->writestring("ref ");
            else if (arg->storageClass & STCin)
                buf->writestring("in ");
            else if (arg->storageClass & STClazy)
                buf->writestring("lazy ");
            else if (arg->storageClass & STCalias)
                buf->writestring("alias ");

            StorageClass stc = arg->storageClass;
            if (arg->type && arg->type->mod & MODshared)
                stc &= ~STCshared;

            StorageClassDeclaration::stcToCBuffer(buf,
                stc & (STCconst | STCimmutable | STCshared | STCscope));

            argbuf.reset();
            if (arg->storageClass & STCalias)
            {   if (arg->ident)
                    argbuf.writestring(arg->ident->toChars());
            }
            else if (arg->type->ty == Tident &&
                     ((TypeIdentifier *)arg->type)->ident->len > 3 &&
                     strncmp(((TypeIdentifier *)arg->type)->ident->string, "__T", 3) == 0)
            {
                // print parameter name, instead of undetermined type parameter
                argbuf.writestring(arg->ident->toChars());
            }
            else
                arg->type->toCBuffer(&argbuf, arg->ident, hgs);
            if (arg->defaultArg)
            {
                argbuf.writestring(" = ");
                arg->defaultArg->toCBuffer(&argbuf, hgs);
            }
            buf->write(&argbuf);
        }
        if (varargs)
        {
            if (arguments->dim && varargs == 1)
                buf->writestring(", ");
            buf->writestring("...");
        }
    }
    buf->writeByte(')');
}

static int argsToDecoBufferDg(void *ctx, size_t n, Parameter *arg)
{
    arg->toDecoBuffer((OutBuffer *)ctx);
    return 0;
}

void Parameter::argsToDecoBuffer(OutBuffer *buf, Parameters *arguments)
{
    //printf("Parameter::argsToDecoBuffer()\n");
    // Write argument types
    foreach(arguments, &argsToDecoBufferDg, buf);
}

/****************************************
 * Determine if parameter list is really a template parameter list
 * (i.e. it has auto or alias parameters)
 */

static int isTPLDg(void *ctx, size_t n, Parameter *arg)
{
    if (arg->storageClass & (STCalias | STCauto | STCstatic))
        return 1;
    return 0;
}

int Parameter::isTPL(Parameters *arguments)
{
    //printf("Parameter::isTPL()\n");
    return foreach(arguments, &isTPLDg, NULL);
}

/****************************************************
 * Determine if parameter is a lazy array of delegates.
 * If so, return the return type of those delegates.
 * If not, return NULL.
 */

Type *Parameter::isLazyArray()
{
//    if (inout == Lazy)
    {
        Type *tb = type->toBasetype();
        if (tb->ty == Tsarray || tb->ty == Tarray)
        {
            Type *tel = ((TypeArray *)tb)->next->toBasetype();
            if (tel->ty == Tdelegate)
            {
                TypeDelegate *td = (TypeDelegate *)tel;
                TypeFunction *tf = (TypeFunction *)td->next;

                if (!tf->varargs && Parameter::dim(tf->parameters) == 0)
                {
                    return tf->next;    // return type of delegate
                }
            }
        }
    }
    return NULL;
}

void Parameter::toDecoBuffer(OutBuffer *buf)
{
    if (storageClass & STCscope)
        buf->writeByte('M');
    switch (storageClass & (STCin | STCout | STCref | STClazy))
    {   case 0:
        case STCin:
            break;
        case STCout:
            buf->writeByte('J');
            break;
        case STCref:
            buf->writeByte('K');
            break;
        case STClazy:
            buf->writeByte('L');
            break;
        default:
#ifdef DEBUG
            printf("storageClass = x%llx\n", storageClass & (STCin | STCout | STCref | STClazy));
            halt();
#endif
            assert(0);
    }
#if 0
    int mod = 0x100;
    if (type->toBasetype()->ty == Tclass)
        mod = 0;
    type->toDecoBuffer(buf, mod);
#else
    //type->toHeadMutable()->toDecoBuffer(buf, 0);
    type->toDecoBuffer(buf, 0);
#endif
}

/***************************************
 * Determine number of arguments, folding in tuples.
 */

static int dimDg(void *ctx, size_t n, Parameter *)
{
    ++*(size_t *)ctx;
    return 0;
}

size_t Parameter::dim(Parameters *args)
{
    size_t n = 0;
    foreach(args, &dimDg, &n);
    return n;
}

/***************************************
 * Get nth Parameter, folding in tuples.
 * Returns:
 *      Parameter*      nth Parameter
 *      NULL            not found, *pn gets incremented by the number
 *                      of Parameters
 */

struct GetNthParamCtx
{
    size_t nth;
    Parameter *arg;
};

static int getNthParamDg(void *ctx, size_t n, Parameter *arg)
{
    GetNthParamCtx *p = (GetNthParamCtx *)ctx;
    if (n == p->nth)
    {   p->arg = arg;
        return 1;
    }
    return 0;
}

Parameter *Parameter::getNth(Parameters *args, size_t nth, size_t *pn)
{
    GetNthParamCtx ctx = { nth, NULL };
    int res = foreach(args, &getNthParamDg, &ctx);
    return res ? ctx.arg : NULL;
}

/***************************************
 * Expands tuples in args in depth first order. Calls
 * dg(void *ctx, size_t argidx, Parameter *arg) for each Parameter.
 * If dg returns !=0, stops and returns that value else returns 0.
 * Use this function to avoid the O(N + N^2/2) complexity of
 * calculating dim and calling N times getNth.
 */

int Parameter::foreach(Parameters *args, Parameter::ForeachDg dg, void *ctx, size_t *pn)
{
    assert(dg);
    if (!args)
        return 0;

    size_t n = pn ? *pn : 0; // take over index
    int result = 0;
    for (size_t i = 0; i < args->dim; i++)
    {   Parameter *arg = (*args)[i];
        Type *t = arg->type->toBasetype();

        if (t->ty == Ttuple)
        {   TypeTuple *tu = (TypeTuple *)t;
            result = foreach(tu->arguments, dg, ctx, &n);
        }
        else
            result = dg(ctx, n++, arg);

        if (result)
            break;
    }

    if (pn)
        *pn = n; // update index
    return result;
}