linker: Introduce linker_verbose debug output

This splits the -Dl RTS debug output into two distinct flags:

 * `+RTS -Dl` shows errors and debug output which scales with at most
   O(# objects)
 * `+RTS -DL` shows debug output which scales with O(# symbols)t

6 files changed, 132 insertions, 115 deletions

diff --git a/rts/Linker.c b/rts/Linker.c
index 1b3caa0a47..57835acc91 100644
--- a/rts/Linker.c
+++ b/rts/Linker.c
@@ -727,7 +727,7 @@ addDLL( pathchar *dll_name )
                                  MAXLINE-1);
       strncpy(line, (errmsg+(match[1].rm_so)),match_length);
       line[match_length] = '\0'; // make sure string is null-terminated
-      IF_DEBUG(linker, debugBelch ("file name = '%s'\n", line));
+      IF_DEBUG(linker, debugBelch("file name = '%s'\n", line));
       if ((fp = __rts_fopen(line, "r")) == NULL) {
          return errmsg; // return original error if open fails
       }
@@ -859,7 +859,7 @@ SymbolAddr* lookupDependentSymbol (SymbolName* lbl, ObjectCode *dependent)
 SymbolAddr* lookupDependentSymbol (SymbolName* lbl, ObjectCode *dependent)
 {
     ASSERT_LOCK_HELD(&linker_mutex);
-    IF_DEBUG(linker, debugBelch("lookupSymbol: looking up '%s'\n", lbl));
+    IF_DEBUG(linker_verbose, debugBelch("lookupSymbol: looking up '%s'\n", lbl));
 
     ASSERT(symhash != NULL);
     RtsSymbolInfo *pinfo;
@@ -876,7 +876,7 @@ SymbolAddr* lookupDependentSymbol (SymbolName* lbl, ObjectCode *dependent)
     }
 
     if (!ghciLookupSymbolInfo(symhash, lbl, &pinfo)) {
-        IF_DEBUG(linker, debugBelch("lookupSymbol: symbol '%s' not found, trying dlsym\n", lbl));
+        IF_DEBUG(linker_verbose, debugBelch("lookupSymbol: symbol '%s' not found, trying dlsym\n", lbl));
 
 #       if defined(OBJFORMAT_ELF)
         SymbolAddr *ret = internal_dlsym(lbl);
@@ -947,9 +947,10 @@ SymbolAddr* lookupDependentSymbol (SymbolName* lbl, ObjectCode *dependent)
  * Symbol name only used for diagnostics output.
  */
 SymbolAddr* loadSymbol(SymbolName *lbl, RtsSymbolInfo *pinfo) {
-    IF_DEBUG(linker, debugBelch("lookupSymbol: value of %s is %p, owned by %" PATH_FMT "\n", lbl,
-                                pinfo->value,
-                                pinfo->owner ? OC_INFORMATIVE_FILENAME(pinfo->owner) : WSTR("No owner, probably built-in.")));
+    IF_DEBUG(linker_verbose,
+             debugBelch("lookupSymbol: value of %s is %p, owned by %" PATH_FMT "\n", lbl,
+                        pinfo->value,
+                        pinfo->owner ? OC_INFORMATIVE_FILENAME(pinfo->owner) : WSTR("No owner, probably built-in.")));
     ObjectCode* oc = pinfo->owner;
 
     /* Symbol can be found during linking, but hasn't been relocated. Do so now.
@@ -1111,7 +1112,7 @@ mmapForLinker (size_t bytes, uint32_t prot, uint32_t flags, int fd, int offset)
      : TRY_MAP_32BIT;
    static uint32_t fixed = 0;
 
-   IF_DEBUG(linker, debugBelch("mmapForLinker: start\n"));
+   IF_DEBUG(linker_verbose, debugBelch("mmapForLinker: start\n"));
    size = roundUpToPage(bytes);
 
 #if defined(MAP_LOW_MEM)
@@ -1122,9 +1123,9 @@ mmap_again:
        map_addr = mmap_32bit_base;
    }
 
-   IF_DEBUG(linker,
+   IF_DEBUG(linker_verbose,
             debugBelch("mmapForLinker: \tprotection %#0x\n", prot));
-   IF_DEBUG(linker,
+   IF_DEBUG(linker_verbose,
             debugBelch("mmapForLinker: \tflags      %#0x\n",
                        MAP_PRIVATE | tryMap32Bit | fixed | flags));
 
@@ -1206,10 +1207,10 @@ mmap_again:
 //   }
 #endif
 
-   IF_DEBUG(linker,
+   IF_DEBUG(linker_verbose,
             debugBelch("mmapForLinker: mapped %" FMT_Word
                        " bytes starting at %p\n", (W_)size, result));
-   IF_DEBUG(linker,
+   IF_DEBUG(linker_verbose,
             debugBelch("mmapForLinker: done\n"));
 
    return result;
@@ -1263,7 +1264,7 @@ void mmapForLinkerMarkExecutable(void *start, size_t len)
     if (len == 0) {
       return;
     }
-    IF_DEBUG(linker,
+    IF_DEBUG(linker_verbose,
              debugBelch("mmapForLinkerMarkExecutable: protecting %" FMT_Word
                         " bytes starting at %p\n", (W_)len, start));
     if (mprotect(start, len, PROT_READ|PROT_EXEC) == -1) {
@@ -1341,6 +1342,8 @@ freePreloadObjectFile (ObjectCode *oc)
  */
 void freeObjectCode (ObjectCode *oc)
 {
+    IF_DEBUG(linker, debugBelch("freeObjectCode: %s", oc->fileName));
+
     if (oc->type == DYNAMIC_OBJECT) {
 #if defined(OBJFORMAT_ELF)
         ACQUIRE_LOCK(&dl_mutex);
@@ -1439,7 +1442,8 @@ mkOc( ObjectType type, pathchar *path, char *image, int imageSize,
       bool mapped, pathchar *archiveMemberName, int misalignment ) {
    ObjectCode* oc;
 
-   IF_DEBUG(linker, debugBelch("mkOc: start\n"));
+
+   IF_DEBUG(linker, debugBelch("mkOc: %s\n", path));
    oc = stgMallocBytes(sizeof(ObjectCode), "mkOc(oc)");
 
    oc->info = NULL;
@@ -1507,7 +1511,6 @@ mkOc( ObjectType type, pathchar *path, char *image, int imageSize,
    oc->nc_ranges = NULL;
    oc->dlopen_handle = NULL;
 
-   IF_DEBUG(linker, debugBelch("mkOc: done\n"));
    return oc;
 }
 
@@ -1694,7 +1697,7 @@ HsInt loadOc (ObjectCode* oc)
 {
    int r;
 
-   IF_DEBUG(linker, debugBelch("loadOc: start\n"));
+   IF_DEBUG(linker, debugBelch("loadOc: start (%s)\n", oc->fileName));
 
    /* verify the in-memory image */
 #  if defined(OBJFORMAT_ELF)
@@ -1778,7 +1781,7 @@ HsInt loadOc (ObjectCode* oc)
            oc->status = OBJECT_LOADED;
        }
    }
-   IF_DEBUG(linker, debugBelch("loadOc: done.\n"));
+   IF_DEBUG(linker, debugBelch("loadOc: done (%s).\n", oc->fileName));
 
    return 1;
 }
diff --git a/rts/RtsFlags.c b/rts/RtsFlags.c
index 0d41108822..426f04a70c 100644
--- a/rts/RtsFlags.c
+++ b/rts/RtsFlags.c
@@ -199,6 +199,7 @@ void initRtsFlagsDefaults(void)
     RtsFlags.DebugFlags.prof            = false;
     RtsFlags.DebugFlags.apply           = false;
     RtsFlags.DebugFlags.linker          = false;
+    RtsFlags.DebugFlags.linker_verbose  = false;
     RtsFlags.DebugFlags.squeeze         = false;
     RtsFlags.DebugFlags.hpc             = false;
     RtsFlags.DebugFlags.sparks          = false;
@@ -2142,6 +2143,9 @@ static void read_debug_flags(const char* arg)
         case 'l':
             RtsFlags.DebugFlags.linker = true;
             break;
+        case 'L':
+            RtsFlags.DebugFlags.linker_verbose = true;
+            break;
         case 'a':
             RtsFlags.DebugFlags.apply = true;
             break;
diff --git a/rts/include/rts/Flags.h b/rts/include/rts/Flags.h
index 9291f492cf..2936876b7a 100644
--- a/rts/include/rts/Flags.h
+++ b/rts/include/rts/Flags.h
@@ -104,7 +104,8 @@ typedef struct _DEBUG_FLAGS {
     bool zero_on_gc;     /* 'Z' */
     bool stable;         /* 't' */
     bool prof;           /* 'p' */
-    bool linker;         /* 'l'   the object linker */
+    bool linker;         /* 'l'   the object linker, output which scales with O(# objects) or errors */
+    bool linker_verbose; /* 'L'   the object linker, output which scales with O(# symbols) */
     bool apply;          /* 'a' */
     bool stm;            /* 'm' */
     bool squeeze;        /* 'z'  stack squeezing & lazy blackholing */
diff --git a/rts/linker/Elf.c b/rts/linker/Elf.c
index f6a1754257..06afae631d 100644
--- a/rts/linker/Elf.c
+++ b/rts/linker/Elf.c
@@ -378,7 +378,7 @@ ocVerifyImage_ELF ( ObjectCode* oc )
       errorBelch("%s: not a relocatable object (.o) file", oc->fileName);
       return 0;
    }
-   IF_DEBUG(linker, debugBelch( "Is a relocatable object (.o) file\n" ));
+   IF_DEBUG(linker,debugBelch( "Is a relocatable object (.o) file\n" ));
 
    IF_DEBUG(linker,debugBelch( "Architecture is " ));
    switch (ehdr->e_machine) {
@@ -446,11 +446,11 @@ ocVerifyImage_ELF ( ObjectCode* oc )
    }
 
    for (i = 0; i < shnum; i++) {
-      IF_DEBUG(linker,debugBelch("%2d:  ", i ));
-      IF_DEBUG(linker,debugBelch("type=%2d  ", (int)shdr[i].sh_type ));
-      IF_DEBUG(linker,debugBelch("size=%4d  ", (int)shdr[i].sh_size ));
-      IF_DEBUG(linker,debugBelch("offs=%4d  ", (int)shdr[i].sh_offset ));
-      IF_DEBUG(linker,debugBelch("  (%p .. %p)  ",
+      IF_DEBUG(linker_verbose,debugBelch("%2d:  ", i ));
+      IF_DEBUG(linker_verbose,debugBelch("type=%2d  ", (int)shdr[i].sh_type ));
+      IF_DEBUG(linker_verbose,debugBelch("size=%4d  ", (int)shdr[i].sh_size ));
+      IF_DEBUG(linker_verbose,debugBelch("offs=%4d  ", (int)shdr[i].sh_offset ));
+      IF_DEBUG(linker_verbose,debugBelch("  (%p .. %p)  ",
                ehdrC + shdr[i].sh_offset,
                       ehdrC + shdr[i].sh_offset + shdr[i].sh_size - 1));
 
@@ -460,7 +460,7 @@ ocVerifyImage_ELF ( ObjectCode* oc )
 
         case SHT_REL:
         case SHT_RELA:
-          IF_DEBUG(linker,debugBelch( shdr[i].sh_type == SHT_REL ? "Rel  " : "RelA "));
+          IF_DEBUG(linker_verbose,debugBelch( shdr[i].sh_type == SHT_REL ? "Rel  " : "RelA "));
 
           if (!SECTION_INDEX_VALID(shdr[i].sh_link)) {
             if (shdr[i].sh_link == SHN_UNDEF)
@@ -488,7 +488,7 @@ ocVerifyImage_ELF ( ObjectCode* oc )
 
           break;
         case SHT_SYMTAB:
-          IF_DEBUG(linker,debugBelch("Sym  "));
+          IF_DEBUG(linker_verbose,debugBelch("Sym  "));
 
           if (!SECTION_INDEX_VALID(shdr[i].sh_link)) {
             errorBelch("\n%s: symbol table section #%d has an invalid link field (%d)\n",
@@ -503,15 +503,15 @@ ocVerifyImage_ELF ( ObjectCode* oc )
             return 0;
           }
           break;
-        case SHT_STRTAB: IF_DEBUG(linker,debugBelch("Str  ")); break;
-        default:         IF_DEBUG(linker,debugBelch("     ")); break;
+        case SHT_STRTAB: IF_DEBUG(linker_verbose,debugBelch("Str  ")); break;
+        default:         IF_DEBUG(linker_verbose,debugBelch("     ")); break;
       }
       if (sh_strtab) {
-          IF_DEBUG(linker,debugBelch("sname=%s\n", sh_strtab + shdr[i].sh_name ));
+          IF_DEBUG(linker_verbose,debugBelch("sname=%s\n", sh_strtab + shdr[i].sh_name ));
       }
    }
 
-   IF_DEBUG(linker,debugBelch( "\nString tables\n" ));
+   IF_DEBUG(linker_verbose,debugBelch( "\nString tables\n" ));
    nstrtab = 0;
    for (i = 0; i < shnum; i++) {
       if (shdr[i].sh_type == SHT_STRTAB
@@ -521,25 +521,25 @@ ocVerifyImage_ELF ( ObjectCode* oc )
              debugging info. */
           && 0 != memcmp(".stabstr", sh_strtab + shdr[i].sh_name, 8)
          ) {
-         IF_DEBUG(linker,debugBelch("   section %d is a normal string table\n", i ));
+         IF_DEBUG(linker_verbose,debugBelch("   section %d is a normal string table\n", i ));
          nstrtab++;
       }
    }
    if (nstrtab == 0) {
-      IF_DEBUG(linker,debugBelch("   no normal string tables (potentially, but not necessarily a problem)\n"));
+      IF_DEBUG(linker_verbose,debugBelch("   no normal string tables (potentially, but not necessarily a problem)\n"));
    }
 #if defined(SHN_XINDEX)
    Elf_Word* shndxTable = get_shndx_table(ehdr);
 #endif
    nsymtabs = 0;
-   IF_DEBUG(linker,debugBelch( "Symbol tables\n" ));
+   IF_DEBUG(linker_verbose,debugBelch( "Symbol tables\n" ));
    for (i = 0; i < shnum; i++) {
       if (shdr[i].sh_type != SHT_SYMTAB) continue;
-      IF_DEBUG(linker,debugBelch( "section %d is a symbol table\n", i ));
+      IF_DEBUG(linker_verbose,debugBelch( "section %d is a symbol table\n", i ));
       nsymtabs++;
       stab = (Elf_Sym*) (ehdrC + shdr[i].sh_offset);
       nent = shdr[i].sh_size / sizeof(Elf_Sym);
-      IF_DEBUG(linker,debugBelch( "   number of entries is apparently %d (%ld rem)\n",
+      IF_DEBUG(linker_verbose,debugBelch( "   number of entries is apparently %d (%ld rem)\n",
                nent,
                (long)shdr[i].sh_size % sizeof(Elf_Sym)
              ));
@@ -556,34 +556,34 @@ ocVerifyImage_ELF ( ObjectCode* oc )
             secno = shndxTable[j];
          }
 #endif
-         IF_DEBUG(linker,debugBelch("   %2d  ", j ));
-         IF_DEBUG(linker,debugBelch("  sec=%-5d  size=%-3d  val=%5p  ",
+         IF_DEBUG(linker_verbose,debugBelch("   %2d  ", j ));
+         IF_DEBUG(linker_verbose,debugBelch("  sec=%-5d  size=%-3d  val=%5p  ",
                              (int)secno,
                              (int)stab[j].st_size,
                              (char*)stab[j].st_value ));
 
-         IF_DEBUG(linker,debugBelch("type=" ));
+         IF_DEBUG(linker_verbose,debugBelch("type=" ));
          switch (ELF_ST_TYPE(stab[j].st_info)) {
-            case STT_NOTYPE:  IF_DEBUG(linker,debugBelch("notype " )); break;
-            case STT_OBJECT:  IF_DEBUG(linker,debugBelch("object " )); break;
-            case STT_FUNC  :  IF_DEBUG(linker,debugBelch("func   " )); break;
-            case STT_SECTION: IF_DEBUG(linker,debugBelch("section" )); break;
-            case STT_FILE:    IF_DEBUG(linker,debugBelch("file   " )); break;
-            default:          IF_DEBUG(linker,debugBelch("?      " )); break;
+            case STT_NOTYPE:  IF_DEBUG(linker_verbose,debugBelch("notype " )); break;
+            case STT_OBJECT:  IF_DEBUG(linker_verbose,debugBelch("object " )); break;
+            case STT_FUNC  :  IF_DEBUG(linker_verbose,debugBelch("func   " )); break;
+            case STT_SECTION: IF_DEBUG(linker_verbose,debugBelch("section" )); break;
+            case STT_FILE:    IF_DEBUG(linker_verbose,debugBelch("file   " )); break;
+            default:          IF_DEBUG(linker_verbose,debugBelch("?      " )); break;
          }
-         IF_DEBUG(linker,debugBelch("  " ));
+         IF_DEBUG(linker_verbose,debugBelch("  " ));
 
-         IF_DEBUG(linker,debugBelch("bind=" ));
+         IF_DEBUG(linker_verbose,debugBelch("bind=" ));
          switch (ELF_ST_BIND(stab[j].st_info)) {
-            case STB_LOCAL :  IF_DEBUG(linker,debugBelch("local " )); break;
-            case STB_GLOBAL:  IF_DEBUG(linker,debugBelch("global" )); break;
-            case STB_WEAK  :  IF_DEBUG(linker,debugBelch("weak  " )); break;
-            default:          IF_DEBUG(linker,debugBelch("?     " )); break;
+            case STB_LOCAL :  IF_DEBUG(linker_verbose,debugBelch("local " )); break;
+            case STB_GLOBAL:  IF_DEBUG(linker_verbose,debugBelch("global" )); break;
+            case STB_WEAK  :  IF_DEBUG(linker_verbose,debugBelch("weak  " )); break;
+            default:          IF_DEBUG(linker_verbose,debugBelch("?     " )); break;
          }
-         IF_DEBUG(linker,debugBelch("  " ));
+         IF_DEBUG(linker_verbose,debugBelch("  " ));
 
-         IF_DEBUG(linker,debugBelch("other=%2x ", stab[j].st_other ));
-         IF_DEBUG(linker,debugBelch("name=%s [%x]\n",
+         IF_DEBUG(linker_verbose,debugBelch("other=%2x ", stab[j].st_other ));
+         IF_DEBUG(linker_verbose,debugBelch("name=%s [%x]\n",
                         ehdrC + shdr[shdr[i].sh_link].sh_offset
                               + stab[j].st_name, stab[j].st_name ));
       }
@@ -593,7 +593,7 @@ ocVerifyImage_ELF ( ObjectCode* oc )
      // Not having a symbol table is not in principle a problem.
      // When an object file has no symbols then the 'strip' program
      // typically will remove the symbol table entirely.
-     IF_DEBUG(linker,debugBelch("   no symbol tables (potentially, but not necessarily a problem)\n"));
+     IF_DEBUG(linker_verbose,debugBelch("   no symbol tables (potentially, but not necessarily a problem)\n"));
    }
 
    return 1;
@@ -928,7 +928,7 @@ ocGetNames_ELF ( ObjectCode* oc )
                    common_used += symbol->elf_sym->st_size;
                    CHECK(common_used <= common_size);
 
-                   IF_DEBUG(linker,
+                   IF_DEBUG(linker_verbose,
                             debugBelch("COMMON symbol, size %llu name %s allocated at %p\n",
                                        (long long unsigned int) symbol->elf_sym->st_size, nm, symbol->addr));
 
@@ -970,7 +970,7 @@ ocGetNames_ELF ( ObjectCode* oc )
                        isLocal = true;
                        isWeak = false;
                    } else { /* STB_GLOBAL or STB_WEAK */
-                       IF_DEBUG(linker,
+                       IF_DEBUG(linker_verbose,
                                 debugBelch("addOTabName(GLOB): %10p  %s %s\n",
                                            symbol->addr, oc->fileName, nm));
                        isLocal = false;
@@ -1000,7 +1000,7 @@ ocGetNames_ELF ( ObjectCode* oc )
                    }
                } else {
                    /* Skip. */
-                   IF_DEBUG(linker,
+                   IF_DEBUG(linker_verbose,
                             debugBelch("skipping `%s'\n",
                                                nm)
                    );
@@ -1068,13 +1068,13 @@ do_Elf_Rel_relocations ( ObjectCode* oc, char* ehdrC,
    CHECK(stab != NULL);
 
    targ  = (Elf_Word*)oc->sections[target_shndx].start;
-   IF_DEBUG(linker,debugBelch(
+   IF_DEBUG(linker_verbose,debugBelch(
                 "relocations for section %d using symtab %d\n",
                 target_shndx, symtab_shndx));
 
    /* Skip sections that we're not interested in. */
    if (oc->sections[target_shndx].kind == SECTIONKIND_OTHER) {
-       IF_DEBUG(linker,debugBelch( "skipping (target section not loaded)"));
+       IF_DEBUG(linker_verbose,debugBelch( "skipping (target section not loaded)"));
        return 1;
    }
 
@@ -1114,10 +1114,10 @@ do_Elf_Rel_relocations ( ObjectCode* oc, char* ehdrC,
 
        ElfSymbol * symbol = NULL;
 
-       IF_DEBUG(linker,debugBelch( "Rel entry %3d is raw(%6p %6p): ",
+       IF_DEBUG(linker_verbose,debugBelch( "Rel entry %3d is raw(%6p %6p): ",
                                    j, (void*)offset, (void*)info ));
        if (!info) {
-           IF_DEBUG(linker,debugBelch( " ZERO" ));
+           IF_DEBUG(linker_verbose,debugBelch( " ZERO" ));
            S = 0;
        } else {
            symbol = &stab->symbols[ELF_R_SYM(info)];
@@ -1133,7 +1133,7 @@ do_Elf_Rel_relocations ( ObjectCode* oc, char* ehdrC,
                           oc->fileName, symbol->name);
                return 0;
            }
-           IF_DEBUG(linker,debugBelch( "`%s' resolves to %p\n", symbol->name,
+           IF_DEBUG(linker_verbose,debugBelch( "`%s' resolves to %p\n", symbol->name,
                                        (void*)S ));
 
 #if defined(arm_HOST_ARCH)
@@ -1172,8 +1172,9 @@ do_Elf_Rel_relocations ( ObjectCode* oc, char* ehdrC,
        }
 
        int reloc_type = ELF_R_TYPE(info);
-       IF_DEBUG(linker,debugBelch("Reloc: P = %p   S = %p   A = %p   type=%d\n",
-                                  (void*)P, (void*)S, (void*)A, reloc_type ));
+       IF_DEBUG(linker_verbose,
+                debugBelch("Reloc: P = %p   S = %p   A = %p   type=%d\n",
+                           (void*)P, (void*)S, (void*)A, reloc_type ));
        checkProddableBlock ( oc, pP, sizeof(Elf_Word) );
 
 #if defined(i386_HOST_ARCH)
@@ -1286,7 +1287,7 @@ do_Elf_Rel_relocations ( ObjectCode* oc, char* ehdrC,
                const StgWord32 hBit = (result & 0x2) >> 1;
                // Change instruction to BLX
                *word = (*word & ~0xFF000000) | ((0xfa | hBit) << 24);
-               IF_DEBUG(linker, debugBelch("Changed BL to BLX at %p\n", word));
+               IF_DEBUG(linker_verbose, debugBelch("Changed BL to BLX at %p\n", word));
            }
            break;
        }
@@ -1489,12 +1490,12 @@ do_Elf_Rela_relocations ( ObjectCode* oc, char* ehdrC,
    stab  = (Elf_Sym*) (ehdrC + shdr[ symtab_shndx ].sh_offset);
    strtab= (char*)    (ehdrC + shdr[ strtab_shndx ].sh_offset);
 
-   IF_DEBUG(linker,debugBelch( "relocations for section %d using symtab %d\n",
+   IF_DEBUG(linker_verbose,debugBelch( "relocations for section %d using symtab %d\n",
                           target_shndx, symtab_shndx ));
 
    /* Skip sections that we're not interested in. */
    if (oc->sections[target_shndx].kind == SECTIONKIND_OTHER) {
-           IF_DEBUG(linker,debugBelch( "skipping (target section not loaded)"));
+           IF_DEBUG(linker_verbose,debugBelch( "skipping (target section not loaded)"));
            return 1;
    }
 
@@ -1520,11 +1521,11 @@ do_Elf_Rela_relocations ( ObjectCode* oc, char* ehdrC,
       Elf_Sword delta;
 #     endif
 
-      IF_DEBUG(linker,debugBelch( "Rel entry %3d is raw(%6p %6p %6p)   ",
+      IF_DEBUG(linker_verbose,debugBelch( "Rel entry %3d is raw(%6p %6p %6p)   ",
                              j, (void*)offset, (void*)info,
                                 (void*)A ));
       if (!info) {
-         IF_DEBUG(linker,debugBelch( " ZERO" ));
+         IF_DEBUG(linker_verbose,debugBelch( " ZERO" ));
          S = 0;
       } else {
          Elf_Sym sym = stab[ELF_R_SYM(info)];
@@ -1583,13 +1584,13 @@ do_Elf_Rela_relocations ( ObjectCode* oc, char* ehdrC,
            errorBelch("%s: unknown symbol `%s'", oc->fileName, symbol);
            return 0;
          }
-         IF_DEBUG(linker,debugBelch("`%s' resolves to %p\n", symbol, (void*)S));
+         IF_DEBUG(linker_verbose,debugBelch("`%s' resolves to %p\n", symbol, (void*)S));
       }
 
 #if defined(DEBUG) || defined(sparc_HOST_ARCH) || defined(powerpc_HOST_ARCH) \
     || defined(x86_64_HOST_ARCH)
-      IF_DEBUG(linker,debugBelch("Reloc: P = %p   S = %p   A = %p\n",
-                                        (void*)P, (void*)S, (void*)A ));
+      IF_DEBUG(linker_verbose,debugBelch("Reloc: P = %p   S = %p   A = %p\n",
+                                         (void*)P, (void*)S, (void*)A ));
       checkProddableBlock(oc, (void*)P, sizeof(Elf_Word));
 #endif
 
diff --git a/rts/linker/MachO.c b/rts/linker/MachO.c
index 1a18ee6a74..02f2a30605 100644
--- a/rts/linker/MachO.c
+++ b/rts/linker/MachO.c
@@ -663,14 +663,14 @@ relocateSection(ObjectCode* oc, int curSection)
         int relocLenBytes;
         int nextInstrAdj = 0;
 
-        IF_DEBUG(linker, debugBelch("relocateSection: relocation %d\n", i));
-        IF_DEBUG(linker, debugBelch("               : type      = %d\n", reloc->r_type));
-        IF_DEBUG(linker, debugBelch("               : address   = %d\n", reloc->r_address));
-        IF_DEBUG(linker, debugBelch("               : symbolnum = %u\n", reloc->r_symbolnum));
-        IF_DEBUG(linker, debugBelch("               : pcrel     = %d\n", reloc->r_pcrel));
-        IF_DEBUG(linker, debugBelch("               : length    = %d\n", reloc->r_length));
-        IF_DEBUG(linker, debugBelch("               : extern    = %d\n", reloc->r_extern));
-        IF_DEBUG(linker, debugBelch("               : type      = %d\n", reloc->r_type));
+        IF_DEBUG(linker_verbose, debugBelch("relocateSection: relocation %d\n", i));
+        IF_DEBUG(linker_verbose, debugBelch("               : type      = %d\n", reloc->r_type));
+        IF_DEBUG(linker_verbose, debugBelch("               : address   = %d\n", reloc->r_address));
+        IF_DEBUG(linker_verbose, debugBelch("               : symbolnum = %u\n", reloc->r_symbolnum));
+        IF_DEBUG(linker_verbose, debugBelch("               : pcrel     = %d\n", reloc->r_pcrel));
+        IF_DEBUG(linker_verbose, debugBelch("               : length    = %d\n", reloc->r_length));
+        IF_DEBUG(linker_verbose, debugBelch("               : extern    = %d\n", reloc->r_extern));
+        IF_DEBUG(linker_verbose, debugBelch("               : type      = %d\n", reloc->r_type));
 
         switch(reloc->r_length)
         {
@@ -714,7 +714,7 @@ relocateSection(ObjectCode* oc, int curSection)
 
 
 
-        IF_DEBUG(linker,
+        IF_DEBUG(linker_verbose,
                  debugBelch("relocateSection: length = %d, thing = %" PRId64 ", baseValue = %p\n",
                             reloc->r_length, thing, (char *)baseValue));
 
@@ -725,7 +725,7 @@ relocateSection(ObjectCode* oc, int curSection)
             SymbolName* nm = symbol->name;
             SymbolAddr* addr = NULL;
 
-            IF_DEBUG(linker, debugBelch("relocateSection: making jump island for %s, extern = %d, X86_64_RELOC_GOT\n",
+            IF_DEBUG(linker_verbose, debugBelch("relocateSection: making jump island for %s, extern = %d, X86_64_RELOC_GOT\n",
                                         nm, reloc->r_extern));
 
             if (reloc->r_extern == 0) {
@@ -739,9 +739,10 @@ relocateSection(ObjectCode* oc, int curSection)
                     // to resolve it.
 
                     addr = lookupDependentSymbol(nm, oc);
-                    IF_DEBUG(linker, debugBelch("relocateSection: looked up %s, "
-                                                "external X86_64_RELOC_GOT or X86_64_RELOC_GOT_LOAD\n"
-                                                "               : addr = %p\n", nm, addr));
+                    IF_DEBUG(linker_verbose,
+                             debugBelch("relocateSection: looked up %s, "
+                                        "external X86_64_RELOC_GOT or X86_64_RELOC_GOT_LOAD\n"
+                                        "               : addr = %p\n", nm, addr));
 
                     if (addr == NULL) {
                             errorBelch("\nlookupSymbol failed in relocateSection (RELOC_GOT)\n"
@@ -749,7 +750,7 @@ relocateSection(ObjectCode* oc, int curSection)
                             return 0;
                     }
             } else {
-                    IF_DEBUG(linker, debugBelch("relocateSection: %s is not an exported symbol\n", nm));
+                    IF_DEBUG(linker_verbose, debugBelch("relocateSection: %s is not an exported symbol\n", nm));
 
                     // The symbol is not exported, or defined in another
                     // module, so it must be in the current object module,
@@ -764,9 +765,11 @@ relocateSection(ObjectCode* oc, int curSection)
 
                         addr = symbol->addr;
 
-                        IF_DEBUG(linker, debugBelch("relocateSection: calculated relocation of "
-                                                    "non-external X86_64_RELOC_GOT or X86_64_RELOC_GOT_LOAD\n"));
-                        IF_DEBUG(linker, debugBelch("               : addr = %p\n", addr));
+                        IF_DEBUG(linker_verbose,
+                                 debugBelch("relocateSection: calculated relocation of "
+                                            "non-external X86_64_RELOC_GOT or X86_64_RELOC_GOT_LOAD\n"));
+                        IF_DEBUG(linker_verbose,
+                                 debugBelch("               : addr = %p\n", addr));
                     } else {
                         errorBelch("\nrelocateSection: %s is not exported,"
                                    " and should be defined in a section, but isn't!\n", nm);
@@ -786,17 +789,18 @@ relocateSection(ObjectCode* oc, int curSection)
             SymbolName* nm = symbol->name;
             SymbolAddr* addr = NULL;
 
-            IF_DEBUG(linker, debugBelch("relocateSection: looking up external symbol %s\n", nm));
-            IF_DEBUG(linker, debugBelch("               : type  = %d\n", symbol->nlist->n_type));
-            IF_DEBUG(linker, debugBelch("               : sect  = %d\n", symbol->nlist->n_sect));
-            IF_DEBUG(linker, debugBelch("               : desc  = %d\n", symbol->nlist->n_desc));
-            IF_DEBUG(linker, debugBelch("               : value = %p\n", (void *)symbol->nlist->n_value));
+            IF_DEBUG(linker_verbose, debugBelch("relocateSection: looking up external symbol %s\n", nm));
+            IF_DEBUG(linker_verbose, debugBelch("               : type  = %d\n", symbol->nlist->n_type));
+            IF_DEBUG(linker_verbose, debugBelch("               : sect  = %d\n", symbol->nlist->n_sect));
+            IF_DEBUG(linker_verbose, debugBelch("               : desc  = %d\n", symbol->nlist->n_desc));
+            IF_DEBUG(linker_verbose, debugBelch("               : value = %p\n", (void *)symbol->nlist->n_value));
 
             if ((symbol->nlist->n_type & N_TYPE) == N_SECT) {
                 CHECK(symbol->addr != NULL);
                 value = (uint64_t) symbol->addr;
-                IF_DEBUG(linker, debugBelch("relocateSection, defined external symbol %s, relocated address %p\n",
-                                            nm, (void *)value));
+                IF_DEBUG(linker_verbose,
+                         debugBelch("relocateSection, defined external symbol %s, relocated address %p\n",
+                                    nm, (void *)value));
             }
             else {
                 addr = lookupDependentSymbol(nm, oc);
@@ -808,7 +812,9 @@ relocateSection(ObjectCode* oc, int curSection)
                 }
 
                 value = (uint64_t) addr;
-                IF_DEBUG(linker, debugBelch("relocateSection: external symbol %s, address %p\n", nm, (void *)value));
+                IF_DEBUG(linker_verbose,
+                         debugBelch("relocateSection: external symbol %s, address %p\n",
+                                    nm, (void *)value));
             }
         }
         else
@@ -832,7 +838,7 @@ relocateSection(ObjectCode* oc, int curSection)
             Section * targetSec = &oc->sections[targetSecNum];
             MachOSection * targetMacho = targetSec->info->macho_section;
 
-            IF_DEBUG(linker,
+            IF_DEBUG(linker_verbose,
                      debugBelch("relocateSection: internal relocation relative to section %d (%s, %s)\n",
                                 targetSecNum, targetMacho->segname, targetMacho->sectname));
 
@@ -843,13 +849,15 @@ relocateSection(ObjectCode* oc, int curSection)
                        thing, (uint64_t) targetMacho->addr);
 
                 uint64_t thingRelativeOffset = thing - targetMacho->addr;
-                IF_DEBUG(linker, debugBelch("                 "
-                                            "unsigned displacement %" PRIx64 " with section relative offset %" PRIx64 "\n",
+                IF_DEBUG(linker_verbose,
+                         debugBelch("                 "
+                                    "unsigned displacement %" PRIx64 " with section relative offset %" PRIx64 "\n",
                                             thing, thingRelativeOffset));
 
                 thing = (uint64_t) targetSec->start + thingRelativeOffset;
-                IF_DEBUG(linker, debugBelch("                 "
-                                            "relocated address is %p\n", (void *) thing));
+                IF_DEBUG(linker_verbose,
+                         debugBelch("                 "
+                                    "relocated address is %p\n", (void *) thing));
 
                 /* Compared to external relocation we don't need to adjust value
                  * any further since thing already has absolute address.
@@ -869,7 +877,7 @@ relocateSection(ObjectCode* oc, int curSection)
                        (void *) imThingLoc, (void *) targetMacho->addr);
 
                 int64_t thingRelativeOffset = imThingLoc - targetMacho->addr;
-                IF_DEBUG(linker,
+                IF_DEBUG(linker_verbose,
                      debugBelch("                 "
                                 "original displacement %" PRId64 " to %p with section relative offset %" PRIu64 "\n",
                                 thing, (void *) imThingLoc, thingRelativeOffset));
@@ -877,7 +885,7 @@ relocateSection(ObjectCode* oc, int curSection)
                 thing = (int64_t) ((uint64_t) targetSec->start + thingRelativeOffset)
                                 - ((uint64_t) sect->start + baseValueOffset);
                 value = baseValue; // so that it further cancels out with baseValue
-                IF_DEBUG(linker,
+                IF_DEBUG(linker_verbose,
                          debugBelch("                 "
                                     "relocated displacement %" PRId64 " to %p\n",
                                     (int64_t) thing, (void *) (baseValue + thing)));
@@ -889,7 +897,7 @@ relocateSection(ObjectCode* oc, int curSection)
             }
         }
 
-        IF_DEBUG(linker, debugBelch("relocateSection: value = %p\n", (void *) value));
+        IF_DEBUG(linker_verbose, debugBelch("relocateSection: value = %p\n", (void *) value));
 
         if (type == X86_64_RELOC_BRANCH)
         {
@@ -924,7 +932,7 @@ relocateSection(ObjectCode* oc, int curSection)
                 barf("unknown relocation");
         }
 
-        IF_DEBUG(linker, debugBelch("relocateSection: thing = %p\n", (void *) thing));
+        IF_DEBUG(linker_verbose, debugBelch("relocateSection: thing = %p\n", (void *) thing));
 
         /* Thing points to memory within one of the relocated sections. We can
          * probe the first byte to sanity check internal relocations.
@@ -1326,7 +1334,7 @@ ocGetNames_MachO(ObjectCode* oc)
             SymbolName* nm = oc->info->macho_symbols[i].name;
             if (oc->info->nlist[i].n_type & N_STAB)
             {
-                IF_DEBUG(linker, debugBelch("ocGetNames_MachO: Skip STAB: %s\n", nm));
+                IF_DEBUG(linker_verbose, debugBelch("ocGetNames_MachO: Skip STAB: %s\n", nm));
             }
             else if ((oc->info->nlist[i].n_type & N_TYPE) == N_SECT)
             {
@@ -1335,11 +1343,11 @@ ocGetNames_MachO(ObjectCode* oc)
                     if (   (oc->info->nlist[i].n_desc & N_WEAK_DEF)
                         && lookupDependentSymbol(nm, oc)) {
                         // weak definition, and we already have a definition
-                        IF_DEBUG(linker, debugBelch("    weak: %s\n", nm));
+                        IF_DEBUG(linker_verbose, debugBelch("    weak: %s\n", nm));
                     }
                     else
                     {
-                            IF_DEBUG(linker, debugBelch("ocGetNames_MachO: inserting %s\n", nm));
+                            IF_DEBUG(linker_verbose, debugBelch("ocGetNames_MachO: inserting %s\n", nm));
                             SymbolAddr* addr = oc->info->macho_symbols[i].addr;
 
                             ghciInsertSymbolTable( oc->fileName
@@ -1356,12 +1364,12 @@ ocGetNames_MachO(ObjectCode* oc)
                 }
                 else
                 {
-                    IF_DEBUG(linker, debugBelch("ocGetNames_MachO: \t...not external, skipping %s\n", nm));
+                    IF_DEBUG(linker_verbose, debugBelch("ocGetNames_MachO: \t...not external, skipping %s\n", nm));
                 }
             }
             else
             {
-                IF_DEBUG(linker, debugBelch("ocGetNames_MachO: \t...not defined in this section, skipping %s\n", nm));
+                IF_DEBUG(linker_verbose, debugBelch("ocGetNames_MachO: \t...not defined in this section, skipping %s\n", nm));
             }
         }
     }
@@ -1384,7 +1392,7 @@ ocGetNames_MachO(ObjectCode* oc)
                 /* also set the final address to the macho_symbol */
                 oc->info->macho_symbols[i].addr = (void*)commonCounter;
 
-                IF_DEBUG(linker, debugBelch("ocGetNames_MachO: inserting common symbol: %s\n", nm));
+                IF_DEBUG(linker_verbose, debugBelch("ocGetNames_MachO: inserting common symbol: %s\n", nm));
                 ghciInsertSymbolTable(oc->fileName, symhash, nm,
                                        (void*)commonCounter, HS_BOOL_FALSE, oc);
                 oc->symbols[curSymbol].name = nm;
diff --git a/rts/linker/PEi386.c b/rts/linker/PEi386.c
index f39930c8c5..9f955e1cf8 100644
--- a/rts/linker/PEi386.c
+++ b/rts/linker/PEi386.c
@@ -1689,7 +1689,7 @@ ocGetNames_PEi386 ( ObjectCode* oc )
             Allocate zeroed space for it from the BSS section */
           addr = bss;
           bss = (SymbolAddr*)((StgWord)bss + (StgWord)symValue);
-          IF_DEBUG(linker, debugBelch("bss symbol @ %p %u\n", addr, symValue));
+          IF_DEBUG(linker_verbose, debugBelch("bss symbol @ %p %u\n", addr, symValue));
       }
       else if (secNumber > 0
                && section
@@ -1708,7 +1708,7 @@ ocGetNames_PEi386 ( ObjectCode* oc )
           sym   = &oc->info->symbols[oc->n_symbols-1];
           sname = get_sym_name (getSymShortName (info, sym), oc);
 
-          IF_DEBUG(linker,
+          IF_DEBUG(linker_verbose,
                    debugBelch("loading symbol `%s' from dll: '%ls' => `%s'\n",
                               sname, oc->fileName, dllName));
 
@@ -1761,7 +1761,7 @@ ocGetNames_PEi386 ( ObjectCode* oc )
          && (!section || (section && section->kind != SECTIONKIND_IMPORT))) {
          /* debugBelch("addSymbol %p `%s' Weak:%lld \n", addr, sname, isWeak); */
          sname = strdup (sname);
-         IF_DEBUG(linker, debugBelch("addSymbol %p `%s'\n", addr, sname));
+         IF_DEBUG(linker_verbose, debugBelch("addSymbol %p `%s'\n", addr, sname));
          ASSERT(i < (uint32_t)oc->n_symbols);
          oc->symbols[i].name = sname;
          oc->symbols[i].addr = addr;
@@ -1869,7 +1869,7 @@ ocResolve_PEi386 ( ObjectCode* oc )
          uint64_t symIndex = reloc->SymbolTableIndex;
          sym = &oc->info->symbols[symIndex];
 
-         IF_DEBUG(linker,
+         IF_DEBUG(linker_verbose,
                   debugBelch(
                             "reloc sec %2d num %3d:  type 0x%-4x   "
                             "vaddr 0x%-8lx   name `",