On FreeBSD, try MAP_FIXED if ordinary mmap() fails to give us suitable memory

[ghc-hetmet.git] / rts / Linker.c

diff --git a/rts/Linker.c b/rts/Linker.c
index 3b2dd1e..ac06cda 100644 (file)
--- a/rts/Linker.c
+++ b/rts/Linker.c
@@ -1302,6 +1302,7 @@ mmapForLinker (size_t bytes, nat flags, int fd)
    void *map_addr = NULL;
    void *result;
    int pagesize, size;
+   static nat fixed = 0;
 
    pagesize = getpagesize();
    size = ROUND_UP(bytes, pagesize);
@@ -1315,10 +1316,11 @@ mmap_again:
 #endif
 
    result = mmap(map_addr, size, PROT_EXEC|PROT_READ|PROT_WRITE,
-                   MAP_PRIVATE|TRY_MAP_32BIT|flags, fd, 0);
+                   MAP_PRIVATE|TRY_MAP_32BIT|fixed|flags, fd, 0);
 
    if (result == MAP_FAILED) {
-       sysErrorBelch("mmap");
+       sysErrorBelch("mmap %lu bytes at %p",(lnat)size,map_addr);
+       errorBelch("Try specifying an address with +RTS -xm<addr> -RTS");
        stg_exit(EXIT_FAILURE);
    }
    
@@ -1329,8 +1331,16 @@ mmap_again:
        } else {
            if ((W_)result > 0x80000000) {
                // oops, we were given memory over 2Gb
-               // ... try allocating memory somewhere else?;
-               barf("loadObj: failed to mmap() memory below 2Gb; asked for %lu bytes at %p, got %p.  Try specifying an address with +RTS -xm<addr> -RTS", size, map_addr, result);
+#if defined(freebsd_HOST_OS)
+               // Some platforms require MAP_FIXED.  This is normally
+               // a bad idea, because MAP_FIXED will overwrite
+               // existing mappings.
+               munmap(result,size);
+               fixed = MAP_FIXED;
+               goto mmap_again;
+#else
+               barf("loadObj: failed to mmap() memory below 2Gb; asked for %lu bytes at %p.  Try specifying an address with +RTS -xm<addr> -RTS", size, map_addr, result);
+#endif
            } else {
                // hmm, we were given memory somewhere else, but it's
                // still under 2Gb so we can use it.  Next time, ask
@@ -1464,7 +1474,6 @@ loadObj( char *path )
    close(fd);
 
 #else /* !USE_MMAP */
-
    /* load the image into memory */
    f = fopen(path, "rb");
    if (!f)
@@ -1492,10 +1501,12 @@ loadObj( char *path )
    oc->image = stgMallocBytes(oc->fileSize, "loadObj(image)");
 #  endif
 
-   n = fread ( oc->image, 1, oc->fileSize, f );
-   if (n != oc->fileSize)
-      barf("loadObj: error whilst reading `%s'", path);
-
+   {
+       int n;
+       n = fread ( oc->image, 1, oc->fileSize, f );
+       if (n != oc->fileSize)
+           barf("loadObj: error whilst reading `%s'", path);
+   }
    fclose(f);
 #endif /* USE_MMAP */
 
@@ -4673,7 +4684,7 @@ static void machoInitSymbolsWithoutUnderscore()
     void **p = symbolsWithoutUnderscore;
     __asm__ volatile(".globl _symbolsWithoutUnderscore\n.data\n_symbolsWithoutUnderscore:");
 
-#undef Sym
+#undef SymI_NeedsProto
 #define SymI_NeedsProto(x)  \
     __asm__ volatile(".long " # x);
 
@@ -4681,13 +4692,13 @@ static void machoInitSymbolsWithoutUnderscore()
 
     __asm__ volatile(".text");
     
-#undef Sym
+#undef SymI_NeedsProto
 #define SymI_NeedsProto(x)  \
     ghciInsertStrHashTable("(GHCi built-in symbols)", symhash, #x, *p++);
     
     RTS_MACHO_NOUNDERLINE_SYMBOLS
     
-#undef Sym
+#undef SymI_NeedsProto
 }
 #endif