diff --git a/src/backend/aa.c b/src/backend/aa.c
index dd57b677abdc..86f54373f7f3 100644
--- a/src/backend/aa.c
+++ b/src/backend/aa.c
@@ -42,6 +42,15 @@ size_t aligntsize(size_t tsize)
     return (tsize + sizeof(size_t) - 1) & ~(sizeof(size_t) - 1);
 }
 
+static int hashCmp(hash_t lhs, hash_t rhs)
+{
+    if (lhs == rhs)
+        return 0;
+    else if (lhs < rhs)
+        return -1;
+    return 1;
+}
+
 /**********************************
  * Constructor.
  */
@@ -122,7 +131,7 @@ void* AArray::get(void *pkey)
     while ((e = *pe) != NULL)
     {   int c;
 
-        c = key_hash - e->hash;
+        c = hashCmp(key_hash, e->hash);
         if (c == 0)
         {
             c = keyti->compare(pkey, e + 1);
@@ -180,7 +189,7 @@ void* AArray::in(void *pkey)
         while (e != NULL)
         {   int c;
 
-            c = key_hash - e->hash;
+            c = hashCmp(key_hash, e->hash);
             if (c == 0)
             {
                 c = keyti->compare(pkey, e + 1);
@@ -218,7 +227,7 @@ void AArray::del(void *pkey)
         while ((e = *pe) != NULL)       // NULL means not found
         {   int c;
 
-            c = key_hash - e->hash;
+            c = hashCmp(key_hash, e->hash);
             if (c == 0)
             {
                 c = keyti->compare(pkey, e + 1);
@@ -412,7 +421,7 @@ void AArray::rehash_x(aaA* olde, aaA** newbuckets, size_t newbuckets_length)
             //printf("\te = %p, e->left = %p, e->right = %p\n", e, e->left, e->right);
             assert(e->left != e);
             assert(e->right != e);
-            c = key_hash - e->hash;
+            c = hashCmp(key_hash, e->hash);
             if (c == 0)
                 c = keyti->compare(olde + 1, e + 1);
             if (c < 0)
diff --git a/src/backend/backconfig.c b/src/backend/backconfig.c
index 9c55916985da..a3b3c19bc5f2 100644
--- a/src/backend/backconfig.c
+++ b/src/backend/backconfig.c
@@ -38,6 +38,7 @@ extern void ph_init();
 void out_config_init(
         int model,      // 32: 32 bit code
                         // 64: 64 bit code
+                        // Windows: set bit 0 to generate MS-COFF instead of OMF
         bool exe,       // true: exe file
                         // false: dll or shared library (generate PIC code)
         bool trace,     // add profiling code
@@ -64,6 +65,8 @@ void out_config_init(
     config.memmodel = 0;
     config.flags |= CFGuchar;   // make sure TYchar is unsigned
     tytab[TYchar] |= TYFLuns;
+    bool mscoff = model & 1;
+    model &= 32 | 64;
 #if TARGET_WINDOS
     if (model == 64)
     {   config.exe = EX_WIN64;
@@ -73,10 +76,12 @@ void out_config_init(
         config.flags |= CFGnoebp;
         config.flags |= CFGalwaysframe;
         config.flags |= CFGromable; // put switch tables in code segment
+        config.objfmt = OBJ_MSCOFF;
     }
     else
     {   config.exe = EX_NT;
         config.flags2 |= CFG2seh;       // Win32 eh
+        config.objfmt = mscoff ? OBJ_MSCOFF : OBJ_OMF;
     }
 
     if (exe)
@@ -98,6 +103,7 @@ void out_config_init(
     config.flags |= CFGalwaysframe;
     if (!exe)
         config.flags3 |= CFG3pic;
+    config.objfmt = OBJ_ELF;
 #endif
 #if TARGET_OSX
     config.fpxmmregs = TRUE;
@@ -112,6 +118,7 @@ void out_config_init(
     if (!exe)
         config.flags3 |= CFG3pic;
     config.flags |= CFGromable; // put switch tables in code segment
+    config.objfmt = OBJ_MACH;
 #endif
 #if TARGET_FREEBSD
     if (model == 64)
@@ -128,6 +135,7 @@ void out_config_init(
     config.flags |= CFGalwaysframe;
     if (!exe)
         config.flags3 |= CFG3pic;
+    config.objfmt = OBJ_ELF;
 #endif
 #if TARGET_OPENBSD
     if (model == 64)
@@ -144,6 +152,7 @@ void out_config_init(
     config.flags |= CFGalwaysframe;
     if (!exe)
         config.flags3 |= CFG3pic;
+    config.objfmt = OBJ_ELF;
 #endif
 #if TARGET_SOLARIS
     if (model == 64)
@@ -160,6 +169,7 @@ void out_config_init(
     config.flags |= CFGalwaysframe;
     if (!exe)
         config.flags3 |= CFG3pic;
+    config.objfmt = OBJ_ELF;
 #endif
     config.flags2 |= CFG2nodeflib;      // no default library
     config.flags3 |= CFG3eseqds;
@@ -189,7 +199,7 @@ void out_config_init(
         config.fulltypes = (symdebug == 1) ? CVDWARF_D : CVDWARF_C;
 #endif
 #if SYMDEB_CODEVIEW
-        if (model == 64)
+        if (config.objfmt == OBJ_MSCOFF)
         {
             configv.addlinenumbers = 1;
             config.fulltypes = CV8;
diff --git a/src/backend/cdef.h b/src/backend/cdef.h
index 53cfc62584d0..2dc46573a62d 100644
--- a/src/backend/cdef.h
+++ b/src/backend/cdef.h
@@ -703,6 +703,11 @@ struct Config
                                    2:   fast inline 8087 code
                                  */
     short memmodel;             // 0:S,X,N,F, 1:M, 2:C, 3:L, 4:V
+    unsigned objfmt;            // target object format
+#define OBJ_OMF         1
+#define OBJ_MSCOFF      2
+#define OBJ_ELF         3
+#define OBJ_MACH        4
     unsigned exe;               // target operating system
 #define EX_DOSX         1       // DOSX 386 program
 #define EX_ZPM          2       // ZPM 286 program
diff --git a/src/backend/cgen.c b/src/backend/cgen.c
index 754653e0bee5..ac2e13926f4d 100644
--- a/src/backend/cgen.c
+++ b/src/backend/cgen.c
@@ -525,7 +525,7 @@ size_t addtofixlist(symbol *s,targ_size_t soffset,int seg,targ_size_t val,int fl
         static char zeros[8];
 
         //printf("addtofixlist(%p '%s')\n",s,s->Sident);
-        assert(flags);
+        assert(I32 || flags);
         fixlist *ln = (fixlist *) mem_calloc(sizeof(fixlist));
         //ln->Lsymbol = s;
         ln->Loffset = soffset;
diff --git a/src/backend/cod1.c b/src/backend/cod1.c
index 978158f34e2e..0bdb6d10f8d6 100644
--- a/src/backend/cod1.c
+++ b/src/backend/cod1.c
@@ -2213,6 +2213,13 @@ code *callclib(elem *e,unsigned clib,regm_t *pretregs,regm_t keepmask)
                 info[CLIBullngdbl].retregs32 = mAX;
                 info[CLIBdblullng].retregs32 = mAX;
             }
+            else if (config.objfmt == OBJ_MSCOFF)
+            {
+                strcpy(lib[CLIBldiv].Sident, "_ms_alldiv");
+                strcpy(lib[CLIBlmod].Sident, "_ms_allrem");   info[CLIBlmod].retregs32 = mAX|mDX;
+                strcpy(lib[CLIBuldiv].Sident, "_ms_aulldiv");
+                strcpy(lib[CLIBulmod].Sident, "_ms_aullrem"); info[CLIBulmod].retregs32 = mAX|mDX;
+            }
         }
         clib_inited++;
   }
diff --git a/src/backend/cod3.c b/src/backend/cod3.c
index 0a9b3cbd8a2c..426d5c5b5df6 100644
--- a/src/backend/cod3.c
+++ b/src/backend/cod3.c
@@ -4152,7 +4152,7 @@ void cod3_thunk(symbol *sthunk,symbol *sfunc,unsigned p,tym_t thisty,
     objmod->pubdef(cseg,sthunk,sthunk->Soffset);
 #endif
 #if TARGET_WINDOS
-    if (config.exe == EX_WIN64)
+    if (config.objfmt == OBJ_MSCOFF)
         objmod->pubdef(cseg,sthunk,sthunk->Soffset);
 #endif
     searchfixlist(sthunk);              /* resolve forward refs */
diff --git a/src/backend/cv8.c b/src/backend/cv8.c
index 980a0764d20f..5c5949861d22 100644
--- a/src/backend/cv8.c
+++ b/src/backend/cv8.c
@@ -277,7 +277,7 @@ void cv8_initmodule(const char *filename, const char *modulename)
 void cv8_termmodule()
 {
     //printf("cv8_termmodule()\n");
-    assert(config.exe == EX_WIN64);
+    assert(config.objfmt == OBJ_MSCOFF);
 }
 
 /******************************************
@@ -614,14 +614,14 @@ void cv8_outsym(Symbol *s)
             buf->writeWordn(0x1111);
             buf->write32(s->Soffset + base + BPoff);
             buf->write32(typidx);
-            buf->writeWordn(334);       // relative to RBP
+            buf->writeWordn(I64 ? 334 : 22);       // relative to RBP/EBP
             cv8_writename(buf, id, len);
             buf->writeByte(0);
 #else
             // This is supposed to work, implicit BP relative addressing, but it does not
             buf->reserve(2 + 2 + 4 + 4 + len + 1);
             buf->writeWordn( 2 + 4 + 4 + len + 1);
-            buf->writeWordn(0x1006);
+            buf->writeWordn(S_BPREL_V3);
             buf->write32(s->Soffset + base + BPoff);
             buf->write32(typidx);
             cv8_writename(buf, id, len);
@@ -864,7 +864,9 @@ idx_t cv8_darray(type *t, idx_t etypidx)
 
     debtyp_t *f = debtyp_alloc(sizeof(fl));
     memcpy(f->data,fl,sizeof(fl));
+    TOLONG(f->data + 6, I64 ? 0x23 : 0x22); // size_t
     TOLONG(f->data + 26, ptridx);
+    TOWORD(f->data + 30, NPTRSIZE);
     idx_t fieldlist = cv_debtyp(f);
 
     const char *id;
@@ -899,7 +901,7 @@ idx_t cv8_darray(type *t, idx_t etypidx)
     TOLONG(d->data + 6, fieldlist);
     TOLONG(d->data + 10, 0);    // dList
     TOLONG(d->data + 14, 0);    // vtshape
-    TOWORD(d->data + 18, 16);   // size
+    TOWORD(d->data + 18, 2 * NPTRSIZE);   // size
     cv_namestring(d->data + 20, id, idlen);
     d->data[20 + idlen] = 0;
 
@@ -966,6 +968,7 @@ idx_t cv8_ddelegate(type *t, idx_t functypidx)
     memcpy(f->data,fl,sizeof(fl));
     TOLONG(f->data + 6, pvidx);
     TOLONG(f->data + 22, ptridx);
+    TOWORD(f->data + 26, NPTRSIZE);
     idx_t fieldlist = cv_debtyp(f);
 
     const char *id = "dDelegate";
@@ -980,7 +983,7 @@ idx_t cv8_ddelegate(type *t, idx_t functypidx)
     TOLONG(d->data + 6, fieldlist);
     TOLONG(d->data + 10, 0);    // dList
     TOLONG(d->data + 14, 0);    // vtshape
-    TOWORD(d->data + 18, 16);   // size
+    TOWORD(d->data + 18, 2 * NPTRSIZE);   // size
     memcpy(d->data + 20, id, idlen);
     d->data[20 + idlen] = 0;
 #endif
diff --git a/src/backend/el.c b/src/backend/el.c
index d36084f321a4..965ab936f3c0 100644
--- a/src/backend/el.c
+++ b/src/backend/el.c
@@ -588,10 +588,18 @@ elem *exp2_copytotemp(elem *e)
 {
     //printf("exp2_copytotemp()\n");
     elem_debug(e);
-    Symbol *stmp = symbol_genauto(e);
+    tym_t ty = tybasic(e->Ety);
+    type *t;
+#if MARS
+    if ((ty == TYstruct || ty == TYarray) && e->ET)
+        t = e->ET;
+    else
+#endif
+        t = type_fake(ty);
+    Symbol *stmp = symbol_genauto(t);
     elem *eeq = el_bin(OPeq,e->Ety,el_var(stmp),e);
     elem *er = el_bin(OPcomma,e->Ety,eeq,el_var(stmp));
-    if (tybasic(e->Ety) == TYstruct || tybasic(e->Ety) == TYarray)
+    if (ty == TYstruct || ty == TYarray)
     {
         eeq->Eoper = OPstreq;
         eeq->ET = e->ET;
diff --git a/src/backend/mscoffobj.c b/src/backend/mscoffobj.c
index badaf20162cc..f588a03ae66e 100644
--- a/src/backend/mscoffobj.c
+++ b/src/backend/mscoffobj.c
@@ -326,7 +326,7 @@ symbol * MsCoffObj::sym_cdata(tym_t ty,char *p,int len)
 int MsCoffObj::data_readonly(char *p, int len, segidx_t *pseg)
 {
     int oldoff;
-    if (I64)
+    if (I64 || I32)
     {
         oldoff = Doffset;
         SegData[DATA]->SDbuf->reserve(len);
@@ -930,19 +930,61 @@ void MsCoffObj::term(const char *objfilename)
                             }
 #endif
                         }
+                        else if (I32)
+                        {
+                            rel.r_type = (r->rtype == RELrel)
+                                    ? IMAGE_REL_I386_REL32
+                                    : IMAGE_REL_I386_DIR32;
+
+                            if (s->Stype->Tty & mTYthread)
+                                rel.r_type = IMAGE_REL_I386_SECREL;
+
+                            if (s->Sclass == SCextern ||
+                                s->Sclass == SCcomdef ||
+                                s->Sclass == SCcomdat ||
+                                s->Sclass == SCglobal)
+                            {
+                                rel.r_vaddr = r->offset;
+                                rel.r_symndx = s->Sxtrnnum;
+                            }
+                            else
+                            {
+                                rel.r_vaddr = r->offset;
+                                rel.r_symndx = s->Sxtrnnum;
+                            }
+                        }
+                        else
+                            assert(false); // not implemented for I16
                     }
                     else
                     {
 //printf("test2\n");
-                        if (pdata)
-                            rel.r_type = IMAGE_REL_AMD64_ADDR32NB;
-                        else
-                            rel.r_type = IMAGE_REL_AMD64_ADDR64;
+                        if (I64)
+                        {
+                            if (pdata)
+                                rel.r_type = IMAGE_REL_AMD64_ADDR32NB;
+                            else
+                                rel.r_type = IMAGE_REL_AMD64_ADDR64;
+
+                            if (r->rtype == RELseg)
+                                rel.r_type = IMAGE_REL_AMD64_SECTION;
+                            else if (r->rtype == RELaddr32)
+                                rel.r_type = IMAGE_REL_AMD64_SECREL;
+                        }
+                        else if (I32)
+                        {
+                            if (pdata)
+                                rel.r_type = IMAGE_REL_I386_DIR32NB;
+                            else
+                                rel.r_type = IMAGE_REL_I386_DIR32;
 
-                        if (r->rtype == RELseg)
-                            rel.r_type = IMAGE_REL_AMD64_SECTION;
-                        else if (r->rtype == RELaddr32)
-                            rel.r_type = IMAGE_REL_AMD64_SECREL;
+                            if (r->rtype == RELseg)
+                                rel.r_type = IMAGE_REL_I386_SECTION;
+                            else if (r->rtype == RELaddr32)
+                                rel.r_type = IMAGE_REL_I386_SECREL;
+                        }
+                        else
+                            assert(false); // not implemented for I16
 
                         rel.r_vaddr = r->offset;
                         rel.r_symndx = s->Sxtrnnum;
@@ -1075,7 +1117,7 @@ printf("test4\n");
                  */
                 //assert(rel.r_symndx <= 20000);
 
-                assert(rel.r_type <= 0x10);
+                assert(rel.r_type <= 0x14);
                 fobjbuf->write(&rel, sizeof(rel));
                 foffset += sizeof(rel);
             }
@@ -1780,34 +1822,36 @@ char *obj_mangle2(Symbol *s,char *dest)
             {
                 char *pstr = unsstr(type_paramsize(s->Stype));
                 size_t pstrlen = strlen(pstr);
-                size_t destlen = len + 1 + pstrlen + 1;
+                size_t prelen = I32 ? 1 : 0;
+                size_t destlen = prelen + len + 1 + pstrlen + 1;
 
                 if (destlen > DEST_LEN)
                     dest = (char *)mem_malloc(destlen);
-                memcpy(dest,name,len);
-                dest[len] = '@';
-                memcpy(dest + 1 + len, pstr, pstrlen + 1);
+                dest[0] = '_';
+                memcpy(dest + prelen,name,len);
+                dest[prelen + len] = '@';
+                memcpy(dest + prelen + 1 + len, pstr, pstrlen + 1);
                 break;
             }
         case mTYman_cpp:
         case mTYman_d:
         case mTYman_sys:
-        case mTYman_c:
+        case_mTYman_c64:
         case 0:
             if (len >= DEST_LEN)
                 dest = (char *)mem_malloc(len + 1);
             memcpy(dest,name,len+1);// copy in name and trailing 0
             break;
 
-#if 0
         case mTYman_c:
+            if(I64)
+                goto case_mTYman_c64;
             // Prepend _ to identifier
             if (len >= DEST_LEN - 1)
                 dest = (char *)mem_malloc(1 + len + 1);
             dest[0] = '_';
             memcpy(dest + 1,name,len+1);// copy in name and trailing 0
             break;
-#endif
 
         default:
 #ifdef DEBUG
@@ -1827,9 +1871,12 @@ char *obj_mangle2(Symbol *s,char *dest)
 
 void MsCoffObj::export_symbol(Symbol *s,unsigned argsize)
 {
+    char dest[DEST_LEN+1];
+    char *destr = obj_mangle2(s, dest);
+
     //printf("MsCoffObj::export_symbol(%s,%d)\n",s->Sident,argsize);
     SegData[segidx_drectve]->SDbuf->write(" /EXPORT:", 9);
-    SegData[segidx_drectve]->SDbuf->write(s->Sident, strlen(s->Sident));
+    SegData[segidx_drectve]->SDbuf->write(dest, strlen(dest));
 }
 
 /*******************************
@@ -2285,6 +2332,8 @@ void MsCoffObj::reftocodeseg(segidx_t seg,targ_size_t offset,targ_size_t val)
     int save = buf->size();
     buf->setsize(offset);
     val -= funcsym_p->Soffset;
+    if (I32)
+        MsCoffObj::addrel(seg, offset, funcsym_p, 0, RELaddr, 0);
 //    MsCoffObj::addrel(seg, offset, funcsym_p, 0, RELaddr);
 //    if (I64)
 //        buf->write64(val);
@@ -2331,7 +2380,7 @@ int MsCoffObj::reftoident(segidx_t seg, targ_size_t offset, Symbol *s, targ_size
     }
     else
     {
-        if (I64)
+        if (I64 || I32)
         {
             //if (s->Sclass != SCcomdat)
                 //val += s->Soffset;
diff --git a/src/backend/out.c b/src/backend/out.c
index d23362b1a5c1..fc730904b5c1 100644
--- a/src/backend/out.c
+++ b/src/backend/out.c
@@ -192,7 +192,7 @@ void outdata(symbol *s)
                             objmod->lidata(pseg->SDseg, pseg->SDoffset, datasize);
 #endif
 #if OMFOBJ
-                            if (config.exe == EX_WIN64)
+                            if (config.objfmt == OBJ_MSCOFF)
                                 objmod->lidata(pseg->SDseg, pseg->SDoffset, datasize);
                             else
                                 pseg->SDoffset += datasize;
@@ -212,7 +212,7 @@ void outdata(symbol *s)
                     if (s->Sclass == SCglobal || s->Sclass == SCstatic) // if a pubdef to be done
 #endif
 #if OMFOBJ
-                    if (s->Sclass == SCglobal || (s->Sclass == SCstatic && I64)) // if a pubdef to be done
+                    if (s->Sclass == SCglobal || (s->Sclass == SCstatic && config.objfmt == OBJ_MSCOFF)) // if a pubdef to be done
 #endif
                         objmod->pubdefsize(s->Sseg,s,s->Soffset,datasize);   // do the definition
                     searchfixlist(s);
@@ -334,7 +334,7 @@ void outdata(symbol *s)
         || s->Sclass == SCstatic
 #endif
 #if OMFOBJ
-        || (s->Sclass == SCstatic && I64)
+        || (s->Sclass == SCstatic && config.objfmt == OBJ_MSCOFF)
 #endif
         )
     {
@@ -480,7 +480,7 @@ void outcommon(symbol *s,targ_size_t n)
             objmod->common_block(s, 0, n, 1);
 #endif
 #if OMFOBJ
-            if (I64)
+            if (config.objfmt == OBJ_MSCOFF)
                 objmod->common_block(s, 0, n, 1);
             else
             {
diff --git a/src/backend/rtlsym.h b/src/backend/rtlsym.h
index 6d16fe31d121..adf65ba4a3d0 100644
--- a/src/backend/rtlsym.h
+++ b/src/backend/rtlsym.h
@@ -95,6 +95,7 @@ SYMBOL_MARS(CALLFINALIZER, FLfunc,FREGSAVED,"_d_callfinalizer", 0, t) \
 SYMBOL_MARS(CALLINTERFACEFINALIZER, FLfunc,FREGSAVED,"_d_callinterfacefinalizer", 0, t) \
 SYMBOL_MARS(DELCLASS,      FLfunc,FREGSAVED,"_d_delclass", 0, t) \
 SYMBOL_MARS(DELINTERFACE,  FLfunc,FREGSAVED,"_d_delinterface", 0, t) \
+SYMBOL_MARS(DELSTRUCT,     FLfunc,FREGSAVED,"_d_delstruct", 0, t) \
 SYMBOL_MARS(ALLOCMEMORY,   FLfunc,FREGSAVED,"_d_allocmemory", 0, t) \
 SYMBOL_MARS(DELARRAY,      FLfunc,FREGSAVED,"_d_delarray", 0, t) \
 SYMBOL_MARS(DELARRAYT,     FLfunc,FREGSAVED,"_d_delarray_t", 0, t) \