[GHC] #15956: Linker error buidling `runghc`

[GHC]

#15956: Linker error buidling `runghc`
-------------------------------------+-------------------------------------
           Reporter:  harpocrates    |             Owner:  (none)
               Type:  bug            |            Status:  new
           Priority:  normal         |         Milestone:  8.6.3
          Component:  Build System   |           Version:  8.6.2
  (Hadrian)                          |
           Keywords:                 |  Operating System:  Unknown/Multiple
       Architecture:                 |   Type of failure:  None/Unknown
  Unknown/Multiple                   |
          Test Case:                 |        Blocked By:
           Blocking:                 |   Related Tickets:
Differential Rev(s):                 |         Wiki Page:
-------------------------------------+-------------------------------------
 I'm on MacOS trying to build `master`. Hadrian fails where `make`
 succeeds. I'm not doing anything fancy either..

 {{{
 ghc$ git rev-parse HEAD
 df570d920fa66db631f936fa377e598fe92bd2a1
 ghc$ ./boot && ./configure
 ghc$ make -j V=0
 # succeeds
 ghc$ ./hadrian/build.sh -c --build-root="_build2" > out.log 2> err.log
 # fails
 }}}

 Hadrian fails when trying to link `runghc`:

 {{{
 Error when running Shake build system:
   at src/Rules.hs:(34,19)-(47,17):
   at src/Rules.hs:47:5-17:
 * Depends on: _build2/stage1/bin/runghc
 * Raised the exception:
 user error (Development.Shake.cmd, system command failed
 Command: _build2/stage0/bin/ghc -Wall -hisuf hi -osuf o -hcsuf hc -static
 -hide-all-packages -no-user-package-db '-package-db
 _build2/stage1/lib/package.conf.d' '-package-id base-4.12.0.0' '-package-
 id directory-1.3.3.1' '-package-id filepath-1.4.2.1' '-package-id
 process-1.6.3.0' '-package-id unix-2.7.2.2' -i
 -i_build2/stage1/utils/runghc/build
 -i_build2/stage1/utils/runghc/build/runghc/autogen -iutils/runghc/.
 -Iincludes -I_build2/generated -I_build2/stage1/utils/runghc/build
 -I/Users/atheriault/Code/ghc/_build2/stage1/lib/x86_64-osx-
 ghc-8.7.20181126/process-1.6.3.0/include
 -I/Users/atheriault/Code/ghc/_build2/stage1/lib/x86_64-osx-
 ghc-8.7.20181126/unix-2.7.2.2/include
 -I/Users/atheriault/Code/ghc/_build2/stage1/lib/x86_64-osx-
 ghc-8.7.20181126/time-1.9.2/include
 -I/Users/atheriault/Code/ghc/_build2/stage1/lib/x86_64-osx-
 ghc-8.7.20181126/bytestring-0.10.9.0/include
 -I/Users/atheriault/Code/ghc/_build2/stage1/lib/x86_64-osx-
 ghc-8.7.20181126/base-4.12.0.0/include
 -I/Users/atheriault/Code/ghc/_build2/stage1/lib/x86_64-osx-
 ghc-8.7.20181126/integer-gmp-1.0.2.0/include
 -I/Users/atheriault/Code/ghc/_build2/stage1/lib/x86_64-osx-
 ghc-8.7.20181126/rts-1.0/include -I_build2/generated -optc-
 I_build2/generated -optP-include
 -optP_build2/stage1/utils/runghc/build/runghc/autogen/cabal_macros.h
 -optc-fno-stack-protector -odir _build2/stage1/utils/runghc/build -hidir
 _build2/stage1/utils/runghc/build -stubdir
 _build2/stage1/utils/runghc/build -no-auto-link-packages -rtsopts -optl-
 lgmp -Wnoncanonical-monad-instances -optc-Wno-unknown-pragmas
 _build2/stage1/utils/runghc/build/Main.o -o _build2/stage1/bin/runghc -O2
 -H32m -XHaskell2010 -ghcversion-
 file=/Users/atheriault/Code/ghc/_build2/generated/ghcversion.h
 Exit code: 1
 Stderr:
 Undefined symbols for architecture x86_64:
   "_findPtr", referenced from:
      -u command line option
 ld: symbol(s) not found for architecture x86_64
 clang: error: linker command failed with exit code 1 (use -v to see
 invocation)
 `gcc' failed in phase `Linker'. (Exit code: 1)
 )
 }}}


 This must be a recent regression, since I was successfully building with
 Hadrian as recently as last week. I'll try to bisect, although the failure
 occurs so late in the compilation pipeline that I expect progress to be
 quite slow.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/15956>
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