Merge pull request #6918 from WalterBright/link-betterC

fix Issue 17521 - -betterC programs should not link in Phobos by default
merged-on-behalf-of: Martin Nowak <code@dawg.eu>

src/ddmd/backend/backconfig.c

@@ -51,7 +51,8 @@ void out_config_init(
                         // 2: fake it with C symbolic debug info
         bool alwaysframe,       // always create standard function frame
         bool stackstomp,        // add stack stomping code
-        bool avx                // use AVX instruction set
+        bool avx,               // use AVX instruction set
+        bool betterC            // implement "Better C"
         )
 {
 #if MARS
@@ -253,6 +254,8 @@ void out_config_init(
     if (stackstomp)
         config.flags2 |= CFG2stomp;
 
+    config.betterC = betterC;
+
     ph_init();
     block_init();
 

src/ddmd/backend/cdef.d

@@ -692,6 +692,7 @@ struct Config
                                 // to near
     linkage_t linkage;          // default function call linkage
     EHmethod ehmethod;          // exception handling method
+    bool betterC;               // implement "Better C"
 
     static uint sizeCheck();
     unittest { assert(sizeCheck() == Config.sizeof); }

src/ddmd/backend/cdef.h

@@ -931,6 +931,7 @@ struct Config
                                 // to near
     linkage_t linkage;          // default function call linkage
     EHmethod ehmethod;          // exception handling method
+    bool betterC;               // implement "Better C"
 
     static unsigned sizeCheck();
 };

src/ddmd/backend/dwarf.c

@@ -98,7 +98,8 @@ bool doUnwindEhFrame()
      * g++ on FreeBSD does not generate mixed frames, while g++ on OSX and Linux does.
      */
     assert(!(usednteh & ~(EHtry | EHcleanup)));
-    return (usednteh & (EHtry | EHcleanup)) || (config.exe & (EX_FREEBSD | EX_FREEBSD64));
+    return (usednteh & (EHtry | EHcleanup)) ||
+           (config.exe & (EX_FREEBSD | EX_FREEBSD64)) && !config.betterC;
 }
 
 #if ELFOBJ

src/ddmd/backend/elfobj.c

@@ -1127,7 +1127,8 @@ void Obj::term(const char *objfilename)
     }
 
 #if MARS
-    obj_rtinit();
+    if (!config.betterC)
+        obj_rtinit();
 #endif
 
 #if SCPP

src/ddmd/dmsc.d

@@ -55,7 +55,8 @@ void out_config_init(
                         // 2: fake it with C symbolic debug info
         bool alwaysframe,       // always create standard function frame
         bool stackstomp,        // add stack stomping code
-        bool avx                // use AVX instruction set
+        bool avx,               // use AVX instruction set
+        bool betterC            // implement "Better C"
         );
 
 void out_config_debug(
@@ -113,7 +114,8 @@ void backend_init()
         params.symdebug,
         params.alwaysframe,
         params.stackstomp,
-        params.cpu >= CPU.avx
+        params.cpu >= CPU.avx,
+        params.betterC
     );
 
     debug

src/ddmd/link.d

@@ -660,12 +660,12 @@ public int runLINK()
             const(char)* p = (*global.params.dllfiles)[i];
             argv.push(p);
         }
-        /* Standard libraries must go after user specified libraries
+        /* D runtime libraries must go after user specified libraries
          * passed with -l.
          */
         const(char)* libname = global.params.symdebug ? global.params.debuglibname : global.params.defaultlibname;
         size_t slen = strlen(libname);
-        if (slen)
+        if (!global.params.betterC && slen)
         {
             char* buf = cast(char*)malloc(3 + slen + 1);
             strcpy(buf, "-l");

test/runnable/cassert.d

@@ -10,7 +10,7 @@ void test(int ij)
     assert(ij,"it is not zero");
 }
 
-int main()
+extern (C) int main()
 {
     test(1);
     return 0;