gcc -o mkDerivedConstantsHdr -O
  -I/export/WRKOBJDIR/lang/ghc/work/ghc-6.4.2/ghc/includes
  -I/export/WRKOBJDIR/lang/ghc/work/ghc-6.4.2/libraries/base/include
  -I/export/WRKOBJDIR/lang/ghc/work/ghc-6.4.2/libraries/unix/include
  -I/export/WRKOBJDIR/lang/ghc/work/ghc-6.4.2/libraries/parsec/include
  -I/export/WRKOBJDIR/lang/ghc/work/ghc-6.4.2/libraries/readline/include
  mkDerivedConstants.o
ld: mkDerivedConstants.o: in function `__gmpn_add':
mkDerivedConstants.c:(.text+0xba): undefined reference to `__gmpn_add_n'
ld: mkDerivedConstants.o: in function `__gmpn_sub':
mkDerivedConstants.c:(.text+0x1f7): undefined reference to `__gmpn_sub_n'
ld: mkDerivedConstants.o: in function `deRefStablePtr':
mkDerivedConstants.c:(.text+0x287): undefined reference to `stable_ptr_table'
Makefile:119: recipe for target 'mkDerivedConstantsHdr' failed
gmake[3]: *** [mkDerivedConstantsHdr] Error 1
../mk/target.mk:1193: recipe for target 'boot' failed
gmake[2]: *** [boot] Error 1
gmake[2]: Leaving directory '/export/WRKOBJDIR/lang/ghc/work/ghc-6.4.2/ghc'
*** Error code 2

Stop.
make[1]: stopped in /export/CHROOT/usr/pkgsrc/lang/ghc
*** Error code 1



fat_entry.o:
00000000 T __gmpn_add_n
0000013c T __gmpn_add_n_init


localhost@makoto 10:52:46/191005(..lang/ghc)% grep -r fat_entry /export/WRKOBJDIR/lang/ghc/work/
Binary file /export/WRKOBJDIR/lang/ghc/work/.buildlink/lib/libgmp.a matches
localhost@makoto 10:53:33/191005(..lang/ghc)% 
  find  /export/WRKOBJDIR/lang/ghc/work/ -name  mkDerivedConstants\* 
/export/WRKOBJDIR/lang/ghc/work/ghc-6.8.3/includes/mkDerivedConstants.c
/export/WRKOBJDIR/lang/ghc/work/ghc-6.4.2/ghc/includes/mkDerivedConstants.c
/export/WRKOBJDIR/lang/ghc/work/ghc-6.4.2/ghc/includes/mkDerivedConstants.o

localhost@makoto 11:05:34/191005(..lang/ghc)% 
(cd /export/WRKOBJDIR/lang/ghc/work/; diff -up ghc-6.4.2/ghc/includes/Makefile{.orig,})
--- ghc-6.4.2/ghc/includes/Makefile.orig        2006-03-28 22:47:04.000000000 +0900
+++ ghc-6.4.2/ghc/includes/Makefile     2019-10-05 11:02:16.810677055 +0900
@@ -116,7 +116,7 @@ else
 mkDerivedConstants.c : $(H_CONFIG) $(H_PLATFORM)
 
 mkDerivedConstantsHdr : mkDerivedConstants.o
-       $(CC) -o $@ $(CC_OPTS) $(LD_OPTS) mkDerivedConstants.o
+       $(CC) -o $@ $(CC_OPTS) $(LD_OPTS) -L/usr/pkg/lib -lgmp mkDerivedConstants.o
 
 DerivedConstants.h : mkDerivedConstantsHdr
        ./mkDerivedConstantsHdr >$@

gcc -o mkDerivedConstantsHdr -O
 -I/export/WRKOBJDIR/lang/ghc/work/ghc-6.4.2/ghc/includes
 -I/export/WRKOBJDIR/lang/ghc/work/ghc-6.4.2/librar ies/base/include
 -I/export/WRKOBJDIR/lang/ghc/work/ghc-6.4.2/libraries/unix/include
 -I/export/WRKOBJDIR/lang/ghc/work/ghc-6.4.2/libraries/parsec/include
 -I/export/WRKOBJDIR/lang/ghc/work/ghc-6.4.2/libraries/readline/include
 -L/usr/pkg/lib -lgmp mkDerivedConstants.o
ld: mkDerivedConstants.o: in function `deRefStablePtr':
mkDerivedConstants.c:(.text+0x287): undefined reference to `stable_ptr_table'
Makefile:119: recipe for target 'mkDerivedConstantsHdr' failed
gmake[3]: *** [mkDerivedConstantsHdr] Error 1
../mk/target.mk:1193: recipe for target 'boot' failed
gmake[2]: *** [boot] Error 1
gmake[2]: Leaving directory '/export/WRKOBJDIR/lang/ghc/work/ghc-6.4.2/ghc'
*** Error code 2

url = https://gitlab.haskell.org/ghc/ghc

*   5700479 [2013-02-19 14:46:21 +0000] Merge branch 'master' of darcs.haskell.org:/srv/darcs//ghc @Ian Lynagh
|\  
| * 767663b [2013-02-18 17:48:43 +1100] DPH: free top-level variables don't prevent encapsulation @Manuel M T Chakravarty
| * dca3a28 [2013-02-18 10:22:57 +0000] 
    declare stable_ptr_table (should fix via-C compilation) @Simon Marlow


* 354cefe [2006-03-24 13:26:13 +0000] mkDerivedConstants.c depends on ghcplatform.h 
   I think this missing dep is what broke my parallel build I used make -j2 
   with ghc-6.4.2.20060323 and got: @Duncan Coutts

86 2019-10-06 11:30 git checkout -f 5700479

localhost@makoto 11:30:32/191006(..git-work/ghc)% grep -r stable_ptr_table .
./includes/rts/Stable.h:extern DLL_IMPORT_RTS spEntry *stable_ptr_table;
./includes/rts/Stable.h:    return stable_ptr_table[(StgWord)sp].addr;