fix Issue 8207 - extern(D) symbols should include another underscore

1. Removed ABI name fiddling from the front-end. 2. Removed `Target.prefixName` and C++ tests for matching `__Z`. 3. Prepend prefixes for C++ and D symbols in the backend only for the targets that require it (Win32, OSX). 4. Removed `RTLSYM__DINVARIANT` runtime library symbol, name is now the same on all targets. 5. Correctly set C++ mangling on `LINK.cpp` symbols, before they were all being set as D mangled symbols. 6. Use System mangling as synonym for do not modify symbol. 7. Added workaround for `extern(D) ___tls_get_addr`.
dlang · Feb 10, 2018 · db29765 · db29765
1 parent 2232b6e
commit db29765
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Showing 16 changed files with 60 additions and 75 deletions.
diff --git a/changelog/fix8207.dd b/changelog/fix8207.dd
@@ -0,0 +1,8 @@
+D ABI change on Win32 and OSX targets
+
+The compiler has been updated to prefix all `extern(D)` symbols with an extra
+underscore where the platform expects one on all external symbols. This allows
+compiled code to work better with binutil programs, such as the ability to list
+symbols demangled inside a debugger.
+
+This is an ABI breaking change and requires recompiling libraries.
diff --git a/src/dmd/backend/cgobj.c b/src/dmd/backend/cgobj.c
@@ -49,6 +49,11 @@ struct Loc
 void error(Loc loc, const char *format, ...);
 #endif
 
+#if MARS
+// C++ name mangling is handled by front end
+#define cpp_mangle(s) ((s)->Sident)
+#endif
+
 #if TARGET_WINDOS
 
 static char __file__[] = __FILE__;      // for tassert.h
@@ -2403,14 +2408,14 @@ size_t Obj::mangle(Symbol *s,char *dest)
                 break;
             }
         case mTYman_c:
+        case mTYman_d:
             if (config.flags4 & CFG4underscore)
             {
                 dest[1] = '_';          // leading _ in name
                 memcpy(&dest[2],name,len);      // copy in name
                 len++;
                 break;
             }
-        case mTYman_d:
         case mTYman_sys:
             memcpy(dest + 1, name, len);        // no mangling
             dest[1 + len] = 0;

diff --git a/src/dmd/backend/machobj.c b/src/dmd/backend/machobj.c
@@ -2111,8 +2111,6 @@ char *obj_mangle2(Symbol *s,char *dest)
                 memcpy(dest + 1 + len, pstr, pstrlen + 1);
                 break;
             }
-        case mTYman_cpp:
-        case mTYman_d:
         case mTYman_sys:
         case 0:
             if (len >= DEST_LEN)
@@ -2121,6 +2119,8 @@ char *obj_mangle2(Symbol *s,char *dest)
             break;
 
         case mTYman_c:
+        case mTYman_cpp:
+        case mTYman_d:
             if (len >= DEST_LEN - 1)
                 dest = (char *)mem_malloc(1 + len + 1);
             dest[0] = '_';

diff --git a/src/dmd/backend/mscoffobj.c b/src/dmd/backend/mscoffobj.c
@@ -45,6 +45,11 @@ static char __file__[] = __FILE__;      // for tassert.h
 #define DEST_LEN (IDMAX + IDOHD + 1)
 char *obj_mangle2(Symbol *s,char *dest);
 
+#if MARS
+// C++ name mangling is handled by front end
+#define cpp_mangle(s) ((s)->Sident)
+#endif
+
 /******************************************
  */
 
@@ -1734,7 +1739,6 @@ char *obj_mangle2(Symbol *s,char *dest)
             }
             // fall through
         case mTYman_cpp:
-        case mTYman_d:
         case mTYman_sys:
         case_mTYman_c64:
         case 0:
@@ -1744,6 +1748,7 @@ char *obj_mangle2(Symbol *s,char *dest)
             break;
 
         case mTYman_c:
+        case mTYman_d:
             if(I64)
                 goto case_mTYman_c64;
             // Prepend _ to identifier

diff --git a/src/dmd/backend/rtlsym.d b/src/dmd/backend/rtlsym.d
@@ -34,7 +34,6 @@ enum
     RTLSYM_DARRAY,
     RTLSYM_DARRAYP,
     RTLSYM_DINVARIANT,
-    RTLSYM__DINVARIANT,
     RTLSYM_MEMCPY,
     RTLSYM_MEMSET8,
     RTLSYM_MEMSET16,

diff --git a/src/dmd/backend/rtlsym.h b/src/dmd/backend/rtlsym.h
@@ -56,8 +56,7 @@ SYMBOL_MARS(DUNITTESTP,      FLfunc,FREGSAVED,"_d_unittestp", 0, t) \
 SYMBOL_MARS(DUNITTEST_MSG,   FLfunc,FREGSAVED,"_d_unittest_msg", 0, t) \
 SYMBOL_MARS(DARRAY,          FLfunc,FREGSAVED,"_d_arraybounds", SFLexit, t) \
 SYMBOL_MARS(DARRAYP,         FLfunc,FREGSAVED,"_d_arrayboundsp", SFLexit, t) \
-SYMBOL_MARS(DINVARIANT,      FLfunc,FREGSAVED,"D9invariant12_d_invariantFC6ObjectZv", 0, tsdlib) \
-SYMBOL_MARS(_DINVARIANT,     FLfunc,FREGSAVED,"_D9invariant12_d_invariantFC6ObjectZv", 0, tsdlib) \
+SYMBOL_MARS(DINVARIANT,      FLfunc,FREGSAVED,"_D9invariant12_d_invariantFC6ObjectZv", 0, tsdlib) \
 SYMBOL_MARS(MEMCPY,          FLfunc,FREGSAVED,"memcpy",    0, t) \
 SYMBOL_MARS(MEMSET8,         FLfunc,FREGSAVED,"memset",    0, t) \
 SYMBOL_MARS(MEMSET16,        FLfunc,FREGSAVED,"_memset16", 0, t) \

diff --git a/src/dmd/cppmangle.d b/src/dmd/cppmangle.d
@@ -49,7 +49,6 @@ const(char)* toCppMangleItanium(Dsymbol s)
 {
     //printf("toCppMangleItanium(%s)\n", s.toChars());
     OutBuffer buf;
-    Target.prefixName(&buf, LINK.cpp);
     scope CppMangleVisitor v = new CppMangleVisitor(&buf, s.loc);
     v.mangleOf(s);
     return buf.extractString();

diff --git a/src/dmd/dmsc.d b/src/dmd/dmsc.d
@@ -193,8 +193,8 @@ extern (C) Symbol *symboldata(targ_size_t offset,tym_t ty)
     Symbol *s = symbol_generate(SClocstat, type_fake(ty));
     s.Sfl = FLdata;
     s.Soffset = offset;
-    s.Stype.Tmangle = mTYman_d; // writes symbol unmodified in Obj::mangle
-    symbol_keep(s);             // keep around
+    s.Stype.Tmangle = mTYman_sys; // writes symbol unmodified in Obj::mangle
+    symbol_keep(s);               // keep around
     return s;
 }
 

diff --git a/src/dmd/e2ir.d b/src/dmd/e2ir.d
@@ -1982,13 +1982,7 @@ elem *toElem(Expression e, IRState *irs)
                     !(cast(TypeClass)t1).sym.isCPPclass())
                 {
                     ts = symbol_genauto(Type_toCtype(t1));
-                    int rtl;
-                    if (global.params.isLinux || global.params.isFreeBSD || global.params.isDragonFlyBSD || global.params.isSolaris ||
-                        global.params.is64bit && global.params.isWindows)
-                        rtl = RTLSYM__DINVARIANT;
-                    else
-                        rtl = RTLSYM_DINVARIANT;
-                    einv = el_bin(OPcall, TYvoid, el_var(getRtlsym(rtl)), el_var(ts));
+                    einv = el_bin(OPcall, TYvoid, el_var(getRtlsym(RTLSYM_DINVARIANT)), el_var(ts));
                 }
                 else if (global.params.useInvariants &&
                     t1.ty == Tpointer &&

diff --git a/src/dmd/glue.d b/src/dmd/glue.d
@@ -968,6 +968,11 @@ void FuncDeclaration_toObjFile(FuncDeclaration fd, bool multiobj)
                 objmod.includelib(libname);
             s.Sclass = SCglobal;
         }
+        else if (fd.ident == Id.tls_get_addr && fd.linkage == LINK.d)
+        {
+            // TODO: Change linkage in druntime to extern(C).
+            f.Fredirect = cast(char*)Id.tls_get_addr.toChars();
+        }
     }
 
     symtab_t *symtabsave = cstate.CSpsymtab;

diff --git a/src/dmd/mtype.d b/src/dmd/mtype.d
@@ -2807,13 +2807,7 @@ extern (C++) abstract class Type : RootObject
         //printf("%p %s, deco = %s, name = %s\n", this, toChars(), deco, name);
         assert(0 < length && length < namelen); // don't overflow the buffer
 
-        int off = 0;
-        static if (!IN_GCC)
-        {
-            if (global.params.isOSX || global.params.isWindows && !global.params.is64bit)
-                ++off; // C mangling will add '_' back in
-        }
-        auto id = Identifier.idPool(name + off, length - off);
+        auto id = Identifier.idPool(name, length);
 
         if (name != namebuf.ptr)
             free(name);

diff --git a/src/dmd/target.d b/src/dmd/target.d
@@ -41,18 +41,23 @@ struct Target
 {
     extern (C++) __gshared
     {
+        // D ABI
         int ptrsize;              /// size of a pointer in bytes
         int realsize;             /// size a real consumes in memory
         int realpad;              /// padding added to the CPU real size to bring it up to realsize
         int realalignsize;        /// alignment for reals
+        int classinfosize;        /// size of `ClassInfo`
+        ulong maxStaticDataSize;  /// maximum size of static data
+
+        // C ABI
+        int c_longsize;           /// size of a C `long` or `unsigned long` type
+        int c_long_doublesize;    /// size of a C `long double`
+
+        // C++ ABI
         bool reverseCppOverloads; /// set if overloaded functions are grouped and in reverse order (such as in dmc and cl)
         bool cppExceptions;       /// set if catching C++ exceptions is supported
         char int64Mangle;         /// mangling character for C++ int64_t
         char uint64Mangle;        /// mangling character for C++ uint64_t
-        int c_longsize;           /// size of a C `long` or `unsigned long` type
-        int c_long_doublesize;    /// size of a C `long double`
-        int classinfosize;        /// size of `ClassInfo`
-        ulong maxStaticDataSize;  /// maximum size of static data
     }
 
     /**
@@ -474,32 +479,6 @@ struct Target
     {
     }
 
-    /**
-     * For the given symbol written to the OutBuffer, apply any
-     * target-specific prefixes based on the given linkage.
-     * Params:
-     *      buf     = buffer to write into
-     *      linkage = extern linkage of decl
-     */
-    extern (C++) static void prefixName(OutBuffer* buf, LINK linkage)
-    {
-        final switch (linkage)
-        {
-        case LINK.cpp:
-            if (global.params.isOSX)
-                buf.prependbyte('_');
-            break;
-        case LINK.default_:
-        case LINK.d:
-        case LINK.c:
-        case LINK.windows:
-        case LINK.pascal:
-        case LINK.objc:
-        case LINK.system:
-            break;
-        }
-    }
-
     /**
      * Mangle the given symbol for C++ ABI.
      * Params:

diff --git a/src/dmd/target.h b/src/dmd/target.h
@@ -28,19 +28,24 @@ struct OutBuffer;
 
 struct Target
 {
+    // D ABI
     static int ptrsize;
-    static int realsize;             // size a real consumes in memory
-    static int realpad;              // 'padding' added to the CPU real size to bring it up to realsize
-    static int realalignsize;        // alignment for reals
-    static bool reverseCppOverloads; // with dmc and cl, overloaded functions are grouped and in reverse order
-    static bool cppExceptions;       // set if catching C++ exceptions is supported
-    static char int64Mangle;         // mangling character for C++ int64_t
-    static char uint64Mangle;        // mangling character for C++ uint64_t
-    static int c_longsize;           // size of a C 'long' or 'unsigned long' type
-    static int c_long_doublesize;    // size of a C 'long double'
-    static int classinfosize;        // size of 'ClassInfo'
+    static int realsize;                // size a real consumes in memory
+    static int realpad;                 // 'padding' added to the CPU real size to bring it up to realsize
+    static int realalignsize;           // alignment for reals
+    static int classinfosize;           // size of 'ClassInfo'
     static unsigned long long maxStaticDataSize;  // maximum size of static data
 
+    // C ABI
+    static int c_longsize;              // size of a C 'long' or 'unsigned long' type
+    static int c_long_doublesize;       // size of a C 'long double'
+
+    // C++ ABI
+    static bool reverseCppOverloads;    // with dmc and cl, overloaded functions are grouped and in reverse order
+    static bool cppExceptions;          // set if catching C++ exceptions is supported
+    static char int64Mangle;            // mangling character for C++ int64_t
+    static char uint64Mangle;           // mangling character for C++ uint64_t
+
     template <typename T>
     struct FPTypeProperties
     {
@@ -75,7 +80,6 @@ struct Target
     static Expression *paintAsType(Expression *e, Type *type);
     // ABI and backend.
     static void loadModule(Module *m);
-    static void prefixName(OutBuffer *buf, LINK linkage);
     static const char *toCppMangle(Dsymbol *s);
     static const char *cppTypeInfoMangle(ClassDeclaration *cd);
     static const char *cppTypeMangle(Type *t);

diff --git a/src/dmd/tocsym.d b/src/dmd/tocsym.d
@@ -263,7 +263,7 @@ Symbol *toSymbol(Dsymbol s)
                     break;
                 case LINK.cpp:
                     s.Sflags |= SFLpublic;
-                    m = mTYman_d;
+                    m = mTYman_cpp;
                     break;
                 case LINK.default_:
                 case LINK.system:
@@ -374,7 +374,7 @@ Symbol *toSymbol(Dsymbol s)
                                 t.Tty = TYmfunc;
                             }
                         }
-                        t.Tmangle = mTYman_d;
+                        t.Tmangle = mTYman_cpp;
                         break;
                     case LINK.default_:
                     case LINK.system:

diff --git a/src/dmd/toobj.d b/src/dmd/toobj.d
@@ -1357,7 +1357,7 @@ void toObjFile(Dsymbol ds, bool multiobj)
                     return mTYman_d;
 
                 case LINK.cpp:
-                    return mTYman_d;
+                    return mTYman_cpp;
 
                 case LINK.default_:
                 case LINK.system:

diff --git a/test/compilable/cppmangle.d b/test/compilable/cppmangle.d
@@ -364,13 +364,7 @@ extern(C++)
     }
 }
 
-version (OSX)
-{
-    static assert(T.foo.mangleof == "__ZNK1T3fooEi");
-    static assert(T.bar.mangleof == "__ZN1T3barEi");
-    static assert(T.boo.mangleof == "__ZN1T3booE");
-}
-else version (Posix)
+version (Posix)
 {
     static assert(T.foo.mangleof == "_ZNK1T3fooEi");
     static assert(T.bar.mangleof == "_ZN1T3barEi");