[GHC] #709: "Fixup too large" error with -fasm on PowerPC

[GHC]

#709: "Fixup too large" error with -fasm on PowerPC
----------------------------------+-----------------------------------------
  Reporter:  simonmar             |          Owner:                            
      Type:  bug                  |         Status:  new                       
  Priority:  low                  |      Milestone:  6.8.1                     
 Component:  Compiler (NCG)       |        Version:  7.7                       
Resolution:                       |       Keywords:                            
        Os:  Unknown/Multiple     |   Architecture:  powerpc                   
   Failure:  Building GHC failed  |     Difficulty:  Moderate (less than a day)
  Testcase:                       |      Blockedby:                            
  Blocking:                       |        Related:                            
----------------------------------+-----------------------------------------
Changes (by PHO):

 * cc: pho@… (added)
  * failure:  => Building GHC failed
  * status:  closed => new
  * resolution:  fixed =>
  * version:  6.4.1 => 7.7


Comment:

 The problem has recurred in HEAD:
 {{{
 "inplace/bin/ghc-stage1" -static -prof  -H32m -O    -package-name
 time-1.4.0.2 -hide-all-packages -i -ilibraries/time/. -ilibraries/time
 /dist-install/build -ilibraries/time/dist-install/build/autogen
 -Ilibraries/time/dist-install/build -Ilibraries/time/dist-
 install/build/autogen -Ilibraries/time/include   -optP-
 DLANGUAGE_Rank2Types -optP-DLANGUAGE_DeriveDataTypeable -optP-
 DLANGUAGE_StandaloneDeriving -optP-include -optPlibraries/time/dist-
 install/build/autogen/cabal_macros.h -package base-4.7.0.0 -package
 deepseq-1.3.0.2 -package old-locale-1.0.0.5  -Wall -XHaskell2010
 -XRank2Types -XDeriveDataTypeable -XStandaloneDeriving -XCPP -O2  -no-
 user-package-db -rtsopts      -odir libraries/time/dist-install/build
 -hidir libraries/time/dist-install/build -stubdir libraries/time/dist-
 install/build -hisuf p_hi -osuf  p_o -hcsuf p_hc -c
 libraries/time/./Data/Time/Format.hs -o libraries/time/dist-
 install/build/Data/Time/Format.p_o

 /var/folders/rN/rNbpGijHEzGPi-
 Ux2JwMgU+++TI/-Tmp-/ghc78514_0/ghc78514_0.s:104514:0:
     Fixup of -33272 too large for field width of 16 bits

 /var/folders/rN/rNbpGijHEzGPi-
 Ux2JwMgU+++TI/-Tmp-/ghc78514_0/ghc78514_0.s:104498:0:
     Fixup of -33636 too large for field width of 16 bits

 /var/folders/rN/rNbpGijHEzGPi-
 Ux2JwMgU+++TI/-Tmp-/ghc78514_0/ghc78514_0.s:94635:0:
     Fixup of 33240 too large for field width of 16 bits

 /var/folders/rN/rNbpGijHEzGPi-
 Ux2JwMgU+++TI/-Tmp-/ghc78514_0/ghc78514_0.s:94632:0:
     Fixup of 33316 too large for field width of 16 bits

 /var/folders/rN/rNbpGijHEzGPi-
 Ux2JwMgU+++TI/-Tmp-/ghc78514_0/ghc78514_0.s:94629:0:
     Fixup of 33392 too large for field width of 16 bits

 /var/folders/rN/rNbpGijHEzGPi-
 Ux2JwMgU+++TI/-Tmp-/ghc78514_0/ghc78514_0.s:94547:0:
     Fixup of 33504 too large for field width of 16 bits

 /var/folders/rN/rNbpGijHEzGPi-
 Ux2JwMgU+++TI/-Tmp-/ghc78514_0/ghc78514_0.s:94486:0:
     Fixup of 33640 too large for field width of 16 bits
 }}}

 I found it was triggered by an extremely large function with lots of info
 tables. While {{{AsmCodeGen.makeFarBranches}}} tries to transform
 problematic {{{PPC.Instr.BCC}}} to {{{PPC.Instr.BCCFAR}}}, it
 underestimates the maximum number of instructions to jump over as it
 doesn't take account of the presence of info tables.

 Here is my
 [https://github.com/phonohawk/ghc/commit/df7b8799b1f008dbcebff0a8566331f298e1bbe1
 patch] to work around:
 {{{
 % git fetch http://github.com/phonohawk/ghc.git ticket-709
 }}}

-- 
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/709#comment:7>
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