I see.  Hmm, I might need to do some debugging on this but it doesn't look so good.

Seems it is not a Fedora specific issue:

http://ghc.haskell.org/trac/ghc/ticket/8134

I did a scratch build to verify the build command where it hangs:

http://ppc.koji.fedoraproject.org/koji/taskinfo?taskID=1396379

"/usr/bin/ghc" -M -dep-makefile compiler/stage1/build/.depend-v.haskell.tmp  -include-pkg-deps -H32m -O -package-db libraries/bootstrapping.conf -package-name ghc-7.6.3 -hide-all-packages -i -icompiler/basicTypes -icompiler/cmm -icompiler/codeGen -icompiler/coreSyn -icompiler/deSugar -icompiler/ghci -icompiler/hsSyn -icompiler/iface -icompiler/llvmGen -icompiler/main -icompiler/nativeGen -icompiler/parser -icompiler/prelude -icompiler/profiling -icompiler/rename -icompiler/simplCore -icompiler/simplStg -icompiler/specialise -icompiler/stgSyn -icompiler/stranal -icompiler/typecheck -icompiler/types -icompiler/utils -icompiler/vectorise -icompiler/stage1/build -icompiler/stage1/build/autogen -Icompiler/stage1/build -Icompiler/stage1/build/autogen -Icompiler/stage1 -Icompiler/. -Icompiler/parser -Icompiler/utils -optP-include -optPcompiler/stage1/build/autogen/cabal_macros.h -package Cabal-1.16.0 -package array-0.4.0.1 -package base-4.6.0.1 -package bin-package-db-0.0.0.0 -package bytestring-0.10.0.2 -package containers-0.5.0.0 -package directory-1.2.0.1 -package filepath-1.3.0.1 -package hoopl-3.9.0.0 -package hpc-0.6.0.0 -package process-1.1.0.2 -package time-1.4.0.1 -package unix-2.6.0.1 -Wall -fno-warn-name-shadowing -fno-warn-orphans -XHaskell98 -XNondecreasingIndentation -XCPP -XMagicHash -XUnboxedTuples -XPatternGuards -XForeignFunctionInterface -XEmptyDataDecls -XTypeSynonymInstances -XMultiParamTypeClasses -XFlexibleInstances -XRankNTypes -XScopedTypeVariables -XDeriveDataTypeable -XBangPatterns -DNO_REGS -DSTAGE=1 -no-user-package-db -rtsopts -odir compiler/stage1/build -hidir compiler/stage1/build -stubdir compiler/stage1/build -hisuf hi -osuf o -hcsuf hc  compiler/basicTypes/Avail.hs  compiler/basicTypes/BasicTypes.lhs  compiler/basicTypes/DataCon.lhs  compiler/basicTypes/Demand.lhs  compiler/utils/Exception.hs  compiler/main/GhcMonad.hs  compiler/basicTypes/Id.lhs  compiler/basicTypes/IdInfo.lhs  compiler/basicTypes/Literal.lhs  compiler/llvmGen/Llvm.hs  compiler/llvmGen/Llvm/AbsSyn.hs  compiler/llvmGen/Llvm/PpLlvm.hs  compiler/llvmGen/Llvm/Types.hs  compiler/llvmGen/LlvmCodeGen.hs  compiler/llvmGen/LlvmCodeGen/Base.hs  compiler/llvmGen/LlvmCodeGen/CodeGen.hs  compiler/llvmGen/LlvmCodeGen/Data.hs  compiler/llvmGen/LlvmCodeGen/Ppr.hs  compiler/llvmGen/LlvmCodeGen/Regs.hs  compiler/llvmGen/LlvmMangler.hs  compiler/basicTypes/MkId.lhs  compiler/basicTypes/Module.lhs  compiler/basicTypes/Name.lhs  compiler/basicTypes/NameEnv.lhs  compiler/basicTypes/NameSet.lhs  compiler/basicTypes/OccName.lhs  compiler/basicTypes/RdrName.lhs  compiler/basicTypes/SrcLoc.lhs  compiler/basicTypes/UniqSupply.lhs  compiler/basicTypes/Unique.lhs  compiler/basicTypes/Var.lhs  compiler/basicTypes/VarEnv.lhs  compiler/basicTypes/VarSet.lhs  compiler/cmm/BlockId.hs  compiler/cmm/CLabel.hs  compiler/cmm/Cmm.hs  compiler/cmm/CmmBuildInfoTables.hs  compiler/cmm/CmmPipeline.hs  compiler/cmm/CmmCallConv.hs  compiler/cmm/CmmCommonBlockElim.hs  compiler/cmm/CmmContFlowOpt.hs  compiler/cmm/CmmCvt.hs  compiler/cmm/CmmExpr.hs  compiler/cmm/CmmInfo.hs  compiler/cmm/CmmLex.hs  compiler/cmm/CmmLint.hs  compiler/cmm/CmmLive.hs  compiler/cmm/CmmMachOp.hs  compiler/cmm/CmmNode.hs  compiler/cmm/CmmOpt.hs  compiler/cmm/CmmParse.hs  compiler/cmm/CmmProcPoint.hs  compiler/cmm/CmmRewriteAssignments.hs  compiler/cmm/CmmSink.hs  compiler/cmm/CmmType.hs  compiler/cmm/CmmUtils.hs  compiler/cmm/CmmLayoutStack.hs  compiler/cmm/MkGraph.hs  compiler/cmm/OldCmm.hs  compiler/cmm/OldCmmLint.hs  compiler/cmm/OldCmmUtils.hs  compiler/cmm/OldPprCmm.hs  compiler/nativeGen/PprBase.hs  compiler/cmm/PprC.hs  compiler/cmm/PprCmm.hs  compiler/cmm/PprCmmDecl.hs  compiler/cmm/PprCmmExpr.hs  compiler/cmm/Bitmap.hs  compiler/codeGen/CgBindery.lhs  compiler/codeGen/CgCallConv.hs  compiler/codeGen/CgCase.lhs  compiler/codeGen/CgClosure.lhs  compiler/codeGen/CgCon.lhs  compiler/codeGen/CgExpr.lhs  compiler/codeGen/CgExtCode.hs  compiler/codeGen/CgForeignCall.hs  compiler/codeGen/CgHeapery.lhs  compiler/codeGen/CgHpc.hs  compiler/codeGen/CgInfoTbls.hs  compiler/codeGen/CgLetNoEscape.lhs  compiler/codeGen/CgMonad.lhs  compiler/codeGen/CgParallel.hs  compiler/codeGen/CgPrimOp.hs  compiler/codeGen/CgProf.hs  compiler/codeGen/CgStackery.lhs  compiler/codeGen/CgTailCall.lhs  compiler/codeGen/CgTicky.hs  compiler/codeGen/CgUtils.hs  compiler/codeGen/StgCmm.hs  compiler/codeGen/StgCmmBind.hs  compiler/codeGen/StgCmmClosure.hs  compiler/codeGen/StgCmmCon.hs  compiler/codeGen/StgCmmEnv.hs  compiler/codeGen/StgCmmExpr.hs  compiler/codeGen/StgCmmForeign.hs  compiler/codeGen/StgCmmGran.hs  compiler/codeGen/StgCmmHeap.hs  compiler/codeGen/StgCmmHpc.hs  compiler/codeGen/StgCmmLayout.hs  compiler/codeGen/StgCmmMonad.hs  compiler/codeGen/StgCmmPrim.hs  compiler/codeGen/StgCmmProf.hs  compiler/codeGen/StgCmmTicky.hs  compiler/codeGen/StgCmmUtils.hs  compiler/codeGen/ClosureInfo.lhs  compiler/codeGen/CodeGen.lhs  compiler/cmm/SMRep.lhs  compiler/coreSyn/CoreArity.lhs  compiler/coreSyn/CoreFVs.lhs  compiler/coreSyn/CoreLint.lhs  compiler/coreSyn/CorePrep.lhs  compiler/coreSyn/CoreSubst.lhs  compiler/coreSyn/CoreSyn.lhs  compiler/coreSyn/TrieMap.lhs  compiler/coreSyn/CoreTidy.lhs  compiler/coreSyn/CoreUnfold.lhs  compiler/coreSyn/CoreUtils.lhs  compiler/coreSyn/ExternalCore.lhs  compiler/coreSyn/MkCore.lhs  compiler/coreSyn/MkExternalCore.lhs  compiler/coreSyn/PprCore.lhs  compiler/coreSyn/PprExternalCore.lhs  compiler/deSugar/Check.lhs  compiler/deSugar/Coverage.lhs  compiler/deSugar/Desugar.lhs  compiler/deSugar/DsArrows.lhs  compiler/deSugar/DsBinds.lhs  compiler/deSugar/DsCCall.lhs  compiler/deSugar/DsExpr.lhs  compiler/deSugar/DsForeign.lhs  compiler/deSugar/DsGRHSs.lhs  compiler/deSugar/DsListComp.lhs  compiler/deSugar/DsMonad.lhs  compiler/deSugar/DsUtils.lhs  compiler/deSugar/Match.lhs  compiler/deSugar/MatchCon.lhs  compiler/deSugar/MatchLit.lhs  compiler/hsSyn/HsBinds.lhs  compiler/hsSyn/HsDecls.lhs  compiler/hsSyn/HsDoc.hs  compiler/hsSyn/HsExpr.lhs  compiler/hsSyn/HsImpExp.lhs  compiler/hsSyn/HsLit.lhs  compiler/hsSyn/HsPat.lhs  compiler/hsSyn/HsSyn.lhs  compiler/hsSyn/HsTypes.lhs  compiler/hsSyn/HsUtils.lhs  compiler/iface/BinIface.hs  compiler/iface/BuildTyCl.lhs  compiler/iface/IfaceEnv.lhs  compiler/iface/IfaceSyn.lhs  compiler/iface/IfaceType.lhs  compiler/iface/LoadIface.lhs  compiler/iface/MkIface.lhs  compiler/iface/TcIface.lhs  compiler/iface/FlagChecker.hs  compiler/main/Annotations.hs  compiler/main/BreakArray.hs  compiler/main/CmdLineParser.hs  compiler/main/CodeOutput.lhs  compiler/stage1/build/Config.hs  compiler/main/Constants.lhs  compiler/main/DriverMkDepend.hs  compiler/main/DriverPhases.hs  compiler/main/DriverPipeline.hs  compiler/main/DynFlags.hs  compiler/main/ErrUtils.lhs  compiler/main/Finder.lhs  compiler/main/GHC.hs  compiler/main/GhcMake.hs  compiler/main/GhcPlugins.hs  compiler/main/DynamicLoading.hs  compiler/main/HeaderInfo.hs  compiler/main/HscMain.hs  compiler/main/HscStats.hs  compiler/main/HscTypes.lhs  compiler/main/InteractiveEval.hs  compiler/main/PackageConfig.hs  compiler/main/Packages.lhs  compiler/main/PprTyThing.hs  compiler/main/StaticFlags.hs  compiler/main/StaticFlagParser.hs  compiler/main/SysTools.lhs  compiler/main/TidyPgm.lhs  compiler/parser/Ctype.lhs  compiler/parser/HaddockUtils.hs  compiler/parser/LexCore.hs  compiler/parser/Lexer.hs  compiler/types/OptCoercion.lhs  compiler/parser/Parser.hs  compiler/parser/ParserCore.hs  compiler/parser/ParserCoreUtils.hs  compiler/parser/RdrHsSyn.lhs  compiler/prelude/ForeignCall.lhs  compiler/prelude/PrelInfo.lhs  compiler/prelude/PrelNames.lhs  compiler/prelude/PrelRules.lhs  compiler/prelude/PrimOp.lhs  compiler/prelude/TysPrim.lhs  compiler/prelude/TysWiredIn.lhs  compiler/profiling/CostCentre.lhs  compiler/profiling/ProfInit.hs  compiler/profiling/SCCfinal.lhs  compiler/rename/RnBinds.lhs  compiler/rename/RnEnv.lhs  compiler/rename/RnExpr.lhs  compiler/rename/RnHsDoc.hs  compiler/rename/RnNames.lhs  compiler/rename/RnPat.lhs  compiler/rename/RnSource.lhs  compiler/rename/RnTypes.lhs  compiler/simplCore/CoreMonad.lhs  compiler/simplCore/CSE.lhs  compiler/simplCore/FloatIn.lhs  compiler/simplCore/FloatOut.lhs  compiler/simplCore/LiberateCase.lhs  compiler/simplCore/OccurAnal.lhs  compiler/simplCore/SAT.lhs  compiler/simplCore/SetLevels.lhs  compiler/simplCore/SimplCore.lhs  compiler/simplCore/SimplEnv.lhs  compiler/simplCore/SimplMonad.lhs  compiler/simplCore/SimplUtils.lhs  compiler/simplCore/Simplify.lhs  compiler/simplStg/SRT.lhs  compiler/simplStg/SimplStg.lhs  compiler/simplStg/StgStats.lhs  compiler/simplStg/UnariseStg.lhs  compiler/specialise/Rules.lhs  compiler/specialise/SpecConstr.lhs  compiler/specialise/Specialise.lhs  compiler/stgSyn/CoreToStg.lhs  compiler/stgSyn/StgLint.lhs  compiler/stgSyn/StgSyn.lhs  compiler/stranal/DmdAnal.lhs  compiler/stranal/WorkWrap.lhs  compiler/stranal/WwLib.lhs  compiler/typecheck/FamInst.lhs  compiler/typecheck/Inst.lhs  compiler/typecheck/TcAnnotations.lhs  compiler/typecheck/TcArrows.lhs  compiler/typecheck/TcBinds.lhs  compiler/typecheck/TcClassDcl.lhs  compiler/typecheck/TcDefaults.lhs  compiler/typecheck/TcDeriv.lhs  compiler/typecheck/TcEnv.lhs  compiler/typecheck/TcExpr.lhs  compiler/typecheck/TcForeign.lhs  compiler/typecheck/TcGenDeriv.lhs  compiler/typecheck/TcGenGenerics.lhs  compiler/typecheck/TcHsSyn.lhs  compiler/typecheck/TcHsType.lhs  compiler/typecheck/TcInstDcls.lhs  compiler/typecheck/TcMType.lhs  compiler/typecheck/TcMatches.lhs  compiler/typecheck/TcPat.lhs  compiler/typecheck/TcRnDriver.lhs  compiler/typecheck/TcRnMonad.lhs  compiler/typecheck/TcRnTypes.lhs  compiler/typecheck/TcRules.lhs  compiler/typecheck/TcSimplify.lhs  compiler/typecheck/TcErrors.lhs  compiler/typecheck/TcTyClsDecls.lhs  compiler/typecheck/TcTyDecls.lhs  compiler/typecheck/TcType.lhs  compiler/typecheck/TcEvidence.lhs  compiler/typecheck/TcUnify.lhs  compiler/typecheck/TcInteract.lhs  compiler/typecheck/TcCanonical.lhs  compiler/typecheck/TcSMonad.lhs  compiler/types/Class.lhs  compiler/types/Coercion.lhs  compiler/types/FamInstEnv.lhs  compiler/types/FunDeps.lhs  compiler/types/InstEnv.lhs  compiler/types/TyCon.lhs  compiler/types/Kind.lhs  compiler/types/Type.lhs  compiler/types/TypeRep.lhs  compiler/types/Unify.lhs  compiler/utils/Bag.lhs  compiler/utils/Binary.hs  compiler/utils/BufWrite.hs  compiler/utils/Digraph.lhs  compiler/utils/Encoding.hs  compiler/utils/FastBool.lhs  compiler/utils/FastFunctions.lhs  compiler/utils/FastMutInt.lhs  compiler/utils/FastString.lhs  compiler/utils/FastTypes.lhs  compiler/stage1/build/Fingerprint.hs  compiler/utils/FiniteMap.lhs  compiler/utils/GraphBase.hs  compiler/utils/GraphColor.hs  compiler/utils/GraphOps.hs  compiler/utils/GraphPpr.hs  compiler/utils/IOEnv.hs  compiler/utils/ListSetOps.lhs  compiler/utils/Maybes.lhs  compiler/utils/MonadUtils.hs  compiler/utils/OrdList.lhs  compiler/utils/Outputable.lhs  compiler/utils/Pair.lhs  compiler/utils/Panic.lhs  compiler/utils/Pretty.lhs  compiler/utils/Serialized.hs  compiler/utils/State.hs  compiler/utils/Stream.hs  compiler/utils/StringBuffer.lhs  compiler/utils/UniqFM.lhs  compiler/utils/UniqSet.lhs  compiler/utils/Util.lhs  compiler/vectorise/Vectorise/Builtins/Base.hs  compiler/vectorise/Vectorise/Builtins/Initialise.hs  compiler/vectorise/Vectorise/Builtins.hs  compiler/vectorise/Vectorise/Monad/Base.hs  compiler/vectorise/Vectorise/Monad/Naming.hs  compiler/vectorise/Vectorise/Monad/Local.hs  compiler/vectorise/Vectorise/Monad/Global.hs  compiler/vectorise/Vectorise/Monad/InstEnv.hs  compiler/vectorise/Vectorise/Monad.hs  compiler/vectorise/Vectorise/Utils/Base.hs  compiler/vectorise/Vectorise/Utils/Closure.hs  compiler/vectorise/Vectorise/Utils/Hoisting.hs  compiler/vectorise/Vectorise/Utils/PADict.hs  compiler/vectorise/Vectorise/Utils/Poly.hs  compiler/vectorise/Vectorise/Utils.hs  compiler/vectorise/Vectorise/Generic/Description.hs  compiler/vectorise/Vectorise/Generic/PAMethods.hs  compiler/vectorise/Vectorise/Generic/PADict.hs  compiler/vectorise/Vectorise/Generic/PData.hs  compiler/vectorise/Vectorise/Type/Env.hs  compiler/vectorise/Vectorise/Type/Type.hs  compiler/vectorise/Vectorise/Type/TyConDecl.hs  compiler/vectorise/Vectorise/Type/Classify.hs  compiler/vectorise/Vectorise/Convert.hs  compiler/vectorise/Vectorise/Vect.hs  compiler/vectorise/Vectorise/Var.hs  compiler/vectorise/Vectorise/Env.hs  compiler/vectorise/Vectorise/Exp.hs  compiler/vectorise/Vectorise.hs  compiler/cmm/Hoopl/Dataflow.hs  compiler/cmm/Hoopl.hs  compiler/nativeGen/AsmCodeGen.lhs  compiler/nativeGen/TargetReg.hs  compiler/nativeGen/NCGMonad.hs  compiler/nativeGen/Instruction.hs  compiler/nativeGen/Size.hs  compiler/nativeGen/Reg.hs  compiler/nativeGen/RegClass.hs  compiler/nativeGen/PIC.hs  compiler/utils/Platform.hs  compiler/nativeGen/CPrim.hs  compiler/nativeGen/X86/Regs.hs  compiler/nativeGen/X86/RegInfo.hs  compiler/nativeGen/X86/Instr.hs  compiler/nativeGen/X86/Cond.hs  compiler/nativeGen/X86/Ppr.hs  compiler/nativeGen/X86/CodeGen.hs  compiler/nativeGen/PPC/Regs.hs  compiler/nativeGen/PPC/RegInfo.hs  compiler/nativeGen/PPC/Instr.hs  compiler/nativeGen/PPC/Cond.hs  compiler/nativeGen/PPC/Ppr.hs  compiler/nativeGen/PPC/CodeGen.hs  compiler/nativeGen/SPARC/Base.hs  compiler/nativeGen/SPARC/Regs.hs  compiler/nativeGen/SPARC/RegPlate.hs  compiler/nativeGen/SPARC/Imm.hs  compiler/nativeGen/SPARC/AddrMode.hs  compiler/nativeGen/SPARC/Cond.hs  compiler/nativeGen/SPARC/Instr.hs  compiler/nativeGen/SPARC/Stack.hs  compiler/nativeGen/SPARC/ShortcutJump.hs  compiler/nativeGen/SPARC/Ppr.hs  compiler/nativeGen/SPARC/CodeGen.hs  compiler/nativeGen/SPARC/CodeGen/Amode.hs  compiler/nativeGen/SPARC/CodeGen/Base.hs  compiler/nativeGen/SPARC/CodeGen/CondCode.hs  compiler/nativeGen/SPARC/CodeGen/Gen32.hs  compiler/nativeGen/SPARC/CodeGen/Gen64.hs  compiler/nativeGen/SPARC/CodeGen/Sanity.hs  compiler/nativeGen/SPARC/CodeGen/Expand.hs  compiler/nativeGen/RegAlloc/Liveness.hs  compiler/nativeGen/RegAlloc/Graph/Main.hs  compiler/nativeGen/RegAlloc/Graph/Stats.hs  compiler/nativeGen/RegAlloc/Graph/ArchBase.hs  compiler/nativeGen/RegAlloc/Graph/ArchX86.hs  compiler/nativeGen/RegAlloc/Graph/Coalesce.hs  compiler/nativeGen/RegAlloc/Graph/Spill.hs  compiler/nativeGen/RegAlloc/Graph/SpillClean.hs  compiler/nativeGen/RegAlloc/Graph/SpillCost.hs  compiler/nativeGen/RegAlloc/Graph/TrivColorable.hs  compiler/nativeGen/RegAlloc/Linear/Main.hs  compiler/nativeGen/RegAlloc/Linear/JoinToTargets.hs  compiler/nativeGen/RegAlloc/Linear/State.hs  compiler/nativeGen/RegAlloc/Linear/Stats.hs  compiler/nativeGen/RegAlloc/Linear/FreeRegs.hs  compiler/nativeGen/RegAlloc/Linear/StackMap.hs  compiler/nativeGen/RegAlloc/Linear/Base.hs  compiler/nativeGen/RegAlloc/Linear/X86/FreeRegs.hs  compiler/nativeGen/RegAlloc/Linear/PPC/FreeRegs.hs  compiler/nativeGen/RegAlloc/Linear/SPARC/FreeRegs.hs

Strace shows a lot of:

futex(0x1002485f65c, FUTEX_WAIT_PRIVATE, 1317, NULL) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
--- SIGVTALRM {si_signo=SIGVTALRM, si_code=SI_TIMER, si_pid=0, si_uid=0, si_value=0} ---
rt_sigreturn()                          = -1100124386908

Okay i dug a little deeper.  Running the command from comment 3
with the ghc verbose flag (ie "ghc -v ...") shows that it seems
to hang on:

'/usr/bin/gcc' '-E' '-undef' '-traditional' '-fno-stack-protector' '-Wl,--hash-size=31' '-Wl,--reduce-memory-overheads' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build' '-I' 'com\
piler/stage1/build/autogen' '-I' 'compiler/stage1' '-I' 'compiler/.' '-I' 'compiler/parser' '-I' 'compiler/utils' '-I' '/usr/lib64/ghc-7.6.3/process-1.1.0.2/include' '-I' '/usr/lib64/ghc-\
7.6.3/old-time-1.1.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/directory-1.2.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/unix-2.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/bytestring-0.10.0.2/inclu\
de' '-I' '/usr/lib64/ghc-7.6.3/time-1.4.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/base-4.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/include' '-D__GLASGOW_HASKELL__=706' '-Dlinux_BUILD_OS=1' \
'-Dpowerpc64_BUILD_ARCH=1' '-Dlinux_HOST_OS=1' '-Dpowerpc64_HOST_ARCH=1' '-include' 'compiler/stage1/build/autogen/cabal_macros.h' '-DNO_REGS' '-DSTAGE=1' '-x' 'c' 'compiler/vectorise/Vec\
torise/Monad/Naming.hs' '-o' '/tmp/ghc31672_0/ghc31672_316.hscpp'

So this looks more like a cpp issue perhaps.

Here is that command without the backquotes:

'/usr/bin/gcc' '-E' '-undef' '-traditional' '-fno-stack-protector' '-Wl,--hash-size=31' '-Wl,--reduce-memory-overheads' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build/autogen' '-I' 'compiler/stage1' '-I' 'compiler/.' '-I' 'compiler/parser' '-I' 'compiler/utils' '-I' '/usr/lib64/ghc-7.6.3/process-1.1.0.2/include' '-I' '/usr/lib64/ghc-7.6.3/old-time-1.1.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/directory-1.2.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/unix-2.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/bytestring-0.10.0.2/include' '-I' '/usr/lib64/ghc-7.6.3/time-1.4.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/base-4.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/include' '-D__GLASGOW_HASKELL__=706' '-Dlinux_BUILD_OS=1' '-Dpowerpc64_BUILD_ARCH=1' '-Dlinux_HOST_OS=1' '-Dpowerpc64_HOST_ARCH=1' '-include' 'compiler/stage1/build/autogen/cabal_macros.h' '-DNO_REGS' '-DSTAGE=1' '-x' 'c' 'compiler/vectorise/Vectorise/Monad/Naming.hs' '-o' '/tmp/ghc31672_0/ghc31672_316.hscpp'

This bug appears to have been reported against 'rawhide' during the Fedora 20 development cycle.
Changing version to '20'.

More information and reason for this action is here:
https://fedoraproject.org/wiki/BugZappers/HouseKeeping/Fedora20

[Pending follow-up comment to above:]

With -v4:

:
*** Literate pre-processor:
'/usr/lib64/ghc-7.6.3/unlit' '-h' 'compiler/iface/LoadIface.lhs' 'compiler/iface/LoadIface.lhs' '/tmp/ghc3416_0/ghc3416_75.lpp'
Running phase Cpp HsSrcFile
*** C pre-processor:
'/usr/bin/gcc' '-E' '-undef' '-traditional' '-fno-stack-protector' '-Wl,--hash-size=31' '-Wl,--reduce-memory-overheads' '-v' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build/autogen' '-I' 'compiler/stage1' '-I' 'compiler/.' '-I' 'compiler/parser' '-I' 'compiler/utils' '-I' '/usr/lib64/ghc-7.6.3/process-1.1.0.2/include' '-I' '/usr/lib64/ghc-7.6.3/old-time-1.1.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/directory-1.2.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/unix-2.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/bytestring-0.10.0.2/include' '-I' '/usr/lib64/ghc-7.6.3/time-1.4.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/base-4.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/include' '-D__GLASGOW_HASKELL__=706' '-Dlinux_BUILD_OS=1' '-Dpowerpc64_BUILD_ARCH=1' '-Dlinux_HOST_OS=1' '-Dpowerpc64_HOST_ARCH=1' '-include' 'compiler/stage1/build/autogen/cabal_macros.h' '-DNO_REGS' '-DSTAGE=1' '-x' 'c' '/tmp/ghc3416_0/ghc3416_75.lpp' '-o' '/tmp/ghc3416_0/ghc3416_152.hscpp'

I need to check of this is reproducible.

I tried doing a bootstrap build of ghc-7.6.2 and it also hung in the same place.

http://ppc.koji.fedoraproject.org/koji/taskinfo?taskID=1423339

Maybe I finally managed to kickoff a verbose build
(by adding GhcStage1HcOpts=-v4 to build.mk in ghc.spec).

http://ppc.koji.fedoraproject.org/koji/taskinfo?taskID=1431718

Also need to set LANG=en_US.utf8 otherwise the encoding of verbose
non-ascii text from some packages fails the build.

http://ppc.koji.fedoraproject.org/koji/taskinfo?taskID=1431755

(In reply to Jens Petersen from comment #11)
> http://ppc.koji.fedoraproject.org/koji/taskinfo?taskID=1431755

This hangs at:

Running phase HsPp HsSrcFile
Running phase Cpp HsSrcFile
*** C pre-processor:
'/usr/bin/gcc' '-E' '-undef' '-traditional' '-fno-stack-protector' '-Wl,--hash-size=31' '-Wl,--reduce-memory-overheads' '-v' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build/autogen' '-I' 'compiler/stage1' '-I' 'compiler/.' '-I' 'compiler/parser' '-I' 'compiler/utils' '-I' '/usr/lib64/ghc-7.6.3/process-1.1.0.2/include' '-I' '/usr/lib64/ghc-7.6.3/old-time-1.1.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/directory-1.2.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/unix-2.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/bytestring-0.10.0.2/include' '-I' '/usr/lib64/ghc-7.6.3/time-1.4.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/base-4.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/include' '-D__GLASGOW_HASKELL__=706' '-Dlinux_BUILD_OS=1' '-Dpowerpc64_BUILD_ARCH=1' '-Dlinux_HOST_OS=1' '-Dpowerpc64_HOST_ARCH=1' '-include' 'compiler/stage1/build/autogen/cabal_macros.h' '-DNO_REGS' '-DSTAGE=1' '-x' 'c' 'compiler/main/HeaderInfo.hs' '-o' '/tmp/ghc38326_0/ghc38326_172.hscpp'
Using built-in specs.
COLLECT_GCC=/usr/bin/gcc
Target: ppc64-redhat-linux
Configured with: ../configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --with-bugurl=http://bugzilla.redhat.com/bugzilla --enable-bootstrap --enable-shared --enable-threads=posix --enable-checking=release --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-gnu-unique-object --enable-linker-build-id --with-linker-hash-style=gnu --enable-languages=c,c++,objc,obj-c++,java,fortran,ada,go,lto --enable-plugin --enable-initfini-array --enable-java-awt=gtk --disable-dssi --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-1.5.0.0/jre --enable-libgcj-multifile --enable-java-maintainer-mode --with-ecj-jar=/usr/share/java/eclipse-ecj.jar --disable-libjava-multilib --with-isl=/builddir/build/BUILD/gcc-4.8.1-20130814/obj-ppc64-redhat-linux/isl-install --with-cloog=/builddir/build/BUILD/gcc-4.8.1-20130814/obj-ppc64-redhat-linux/cloog-install --enable-secureplt --with-long-double-128 --build=ppc64-redhat-linux
Thread model: posix
gcc version 4.8.1 20130814 (Red Hat 4.8.1-6) (GCC) 
COLLECT_GCC_OPTIONS='-E' '-undef' '-traditional' '-fno-stack-protector' '-v' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build/autogen' '-I' 'compiler/stage1' '-I' 'compiler/.' '-I' 'compiler/parser' '-I' 'compiler/utils' '-I' '/usr/lib64/ghc-7.6.3/process-1.1.0.2/include' '-I' '/usr/lib64/ghc-7.6.3/old-time-1.1.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/directory-1.2.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/unix-2.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/bytestring-0.10.0.2/include' '-I' '/usr/lib64/ghc-7.6.3/time-1.4.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/base-4.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/include' '-D' '__GLASGOW_HASKELL__=706' '-D' 'linux_BUILD_OS=1' '-D' 'powerpc64_BUILD_ARCH=1' '-D' 'linux_HOST_OS=1' '-D' 'powerpc64_HOST_ARCH=1' '-include' 'compiler/stage1/build/autogen/cabal_macros.h' '-D' 'NO_REGS' '-D' 'STAGE=1' '-o' '/tmp/ghc38326_0/ghc38326_172.hscpp'
 /usr/libexec/gcc/ppc64-redhat-linux/4.8.1/cc1 -E -traditional-cpp -quiet -v -I compiler/stage1/build -I compiler/stage1/build -I compiler/stage1/build/autogen -I compiler/stage1 -I compiler/. -I compiler/parser -I compiler/utils -I /usr/lib64/ghc-7.6.3/process-1.1.0.2/include -I /usr/lib64/ghc-7.6.3/old-time-1.1.0.1/include -I /usr/lib64/ghc-7.6.3/directory-1.2.0.1/include -I /usr/lib64/ghc-7.6.3/unix-2.6.0.1/include -I /usr/lib64/ghc-7.6.3/bytestring-0.10.0.2/include -I /usr/lib64/ghc-7.6.3/time-1.4.0.1/include -I /usr/lib64/ghc-7.6.3/base-4.6.0.1/include -I /usr/lib64/ghc-7.6.3/include -D__unix__ -D__gnu_linux__ -D__linux__ -Asystem=linux -Asystem=unix -Asystem=posix -D __GLASGOW_HASKELL__=706 -D linux_BUILD_OS=1 -D powerpc64_BUILD_ARCH=1 -D linux_HOST_OS=1 -D powerpc64_HOST_ARCH=1 -D NO_REGS -D STAGE=1 -include compiler/stage1/build/autogen/cabal_macros.h compiler/main/HeaderInfo.hs -o /tmp/ghc38326_0/ghc38326_172.hscpp -msecure-plt -fno-stack-protector -undef
ignoring nonexistent directory "/usr/lib/gcc/ppc64-redhat-linux/4.8.1/include-fixed"
ignoring nonexistent directory "/usr/lib/gcc/ppc64-redhat-linux/4.8.1/../../../../ppc64-redhat-linux/include"
ignoring duplicate directory "compiler/stage1/build"
#include "..." search starts here:
#include <...> search starts here:
 compiler/stage1/build
 compiler/stage1/build/autogen
 compiler/stage1
 compiler/.
 compiler/parser
 compiler/utils
 /usr/lib64/ghc-7.6.3/process-1.1.0.2/include
 /usr/lib64/ghc-7.6.3/old-time-1.1.0.1/include
 /usr/lib64/ghc-7.6.3/directory-1.2.0.1/include
 /usr/lib64/ghc-7.6.3/unix-2.6.0.1/include
 /usr/lib64/ghc-7.6.3/bytestring-0.10.0.2/include
 /usr/lib64/ghc-7.6.3/time-1.4.0.1/include
 /usr/lib64/ghc-7.6.3/base-4.6.0.1/include
 /usr/lib64/ghc-7.6.3/include
 /usr/lib/gcc/ppc64-redhat-linux/4.8.1/include
 /usr/local/include
 /usr/include
End of search list.
COMPILER_PATH=/usr/libexec/gcc/ppc64-redhat-linux/4.8.1/:/usr/libexec/gcc/ppc64-redhat-linux/4.8.1/:/usr/libexec/gcc/ppc64-redhat-linux/:/usr/lib/gcc/ppc64-redhat-linux/4.8.1/:/usr/lib/gcc/ppc64-redhat-linux/
LIBRARY_PATH=/usr/lib/gcc/ppc64-redhat-linux/4.8.1/:/usr/lib/gcc/ppc64-redhat-linux/4.8.1/../../../../lib64/:/lib/../lib64/:/usr/lib/../lib64/:/usr/lib/gcc/ppc64-redhat-linux/4.8.1/../../../:/lib/:/usr/lib/
COLLECT_GCC_OPTIONS='-E' '-undef' '-traditional' '-fno-stack-protector' '-v' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build/autogen' '-I' 'compiler/stage1' '-I' 'compiler/.' '-I' 'compiler/parser' '-I' 'compiler/utils' '-I' '/usr/lib64/ghc-7.6.3/process-1.1.0.2/include' '-I' '/usr/lib64/ghc-7.6.3/old-time-1.1.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/directory-1.2.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/unix-2.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/bytestring-0.10.0.2/include' '-I' '/usr/lib64/ghc-7.6.3/time-1.4.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/base-4.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/include' '-D' '__GLASGOW_HASKELL__=706' '-D' 'linux_BUILD_OS=1' '-D' 'powerpc64_BUILD_ARCH=1' '-D' 'linux_HOST_OS=1' '-D' 'powerpc64_HOST_ARCH=1' '-include' 'compiler/stage1/build/autogen/cabal_macros.h' '-D' 'NO_REGS' '-D' 'STAGE=1' '-o' '/tmp/ghc38326_0/ghc38326_172.hscpp'
Running phase HsPp HsSrcFile
Running phase Cpp HsSrcFile
*** C pre-processor:
'/usr/bin/gcc' '-E' '-undef' '-traditional' '-fno-stack-protector' '-Wl,--hash-size=31' '-Wl,--reduce-memory-overheads' '-v' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build/autogen' '-I' 'compiler/stage1' '-I' 'compiler/.' '-I' 'compiler/parser' '-I' 'compiler/utils' '-I' '/usr/lib64/ghc-7.6.3/process-1.1.0.2/include' '-I' '/usr/lib64/ghc-7.6.3/old-time-1.1.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/directory-1.2.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/unix-2.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/bytestring-0.10.0.2/include' '-I' '/usr/lib64/ghc-7.6.3/time-1.4.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/base-4.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/include' '-D__GLASGOW_HASKELL__=706' '-Dlinux_BUILD_OS=1' '-Dpowerpc64_BUILD_ARCH=1' '-Dlinux_HOST_OS=1' '-Dpowerpc64_HOST_ARCH=1' '-include' 'compiler/stage1/build/autogen/cabal_macros.h' '-DNO_REGS' '-DSTAGE=1' '-x' 'c' 'compiler/main/HscMain.hs' '-o' '/tmp/ghc38326_0/ghc38326_173.hscpp'


cf comment 8

http://s390.koji.fedoraproject.org/koji/taskinfo?taskID=1220128 hung at

Running phase HsPp HsSrcFile
Running phase Unlit HsSrcFile
*** Literate pre-processor:
'/usr/lib64/ghc-7.6.3/unlit' '-h' 'compiler/coreSyn/ExternalCore.lhs' 'compiler/coreSyn/ExternalCore.lhs' '/tmp/ghc36897_0/ghc36897_42.lpp'
Running phase Cpp HsSrcFile
*** C pre-processor:
'/usr/bin/gcc' '-E' '-undef' '-traditional' '-fno-stack-protector' '-Wl,--hash-size=31' '-Wl,--reduce-memory-overheads' '-v' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build/autogen' '-I' 'compiler/stage1' '-I' 'compiler/.' '-I' 'compiler/parser' '-I' 'compiler/utils' '-I' '/usr/lib64/ghc-7.6.3/process-1.1.0.2/include' '-I' '/usr/lib64/ghc-7.6.3/old-time-1.1.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/directory-1.2.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/unix-2.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/bytestring-0.10.0.2/include' '-I' '/usr/lib64/ghc-7.6.3/time-1.4.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/base-4.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/include' '-D__GLASGOW_HASKELL__=706' '-Dlinux_BUILD_OS=1' '-Ds390x_BUILD_ARCH=1' '-Dlinux_HOST_OS=1' '-Ds390x_HOST_ARCH=1' '-include' 'compiler/stage1/build/autogen/cabal_macros.h' '-DNO_REGS' '-DSTAGE=1' '-x' 'c' '/tmp/ghc36897_0/ghc36897_42.lpp' '-o' '/tmp/ghc36897_0/ghc36897_117.hscpp'
Using built-in specs.
COLLECT_GCC=/usr/bin/gcc
Target: s390x-redhat-linux
Configured with: ../configure --prefix=/usr --mandir=/usr/share/man --infodir=/usr/share/info --with-bugurl=http://bugzilla.redhat.com/bugzilla --enable-bootstrap --enable-shared --enable-threads=posix --enable-checking=release --with-system-zlib --enable-__cxa_atexit --disable-libunwind-exceptions --enable-gnu-unique-object --enable-linker-build-id --with-linker-hash-style=gnu --enable-languages=c,c++,objc,obj-c++,java,fortran,go,lto --enable-plugin --enable-initfini-array --enable-java-awt=gtk --disable-dssi --with-java-home=/usr/lib/jvm/java-1.5.0-gcj-1.5.0.0/jre --enable-libgcj-multifile --enable-java-maintainer-mode --with-ecj-jar=/usr/share/java/eclipse-ecj.jar --disable-libjava-multilib --with-isl=/builddir/build/BUILD/gcc-4.8.1-20130814/obj-s390x-redhat-linux/isl-install --with-cloog=/builddir/build/BUILD/gcc-4.8.1-20130814/obj-s390x-redhat-linux/cloog-install --with-long-double-128 --with-arch=z9-109 --with-tune=z10 --enable-decimal-float --build=s390x-redhat-linux
Thread model: posix
gcc version 4.8.1 20130814 (Red Hat 4.8.1-6) (GCC) 
COLLECT_GCC_OPTIONS='-E' '-undef' '-traditional' '-fno-stack-protector' '-v' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build' '-I' 'compiler/stage1/build/autogen' '-I' 'compiler/stage1' '-I' 'compiler/.' '-I' 'compiler/parser' '-I' 'compiler/utils' '-I' '/usr/lib64/ghc-7.6.3/process-1.1.0.2/include' '-I' '/usr/lib64/ghc-7.6.3/old-time-1.1.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/directory-1.2.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/unix-2.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/bytestring-0.10.0.2/include' '-I' '/usr/lib64/ghc-7.6.3/time-1.4.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/base-4.6.0.1/include' '-I' '/usr/lib64/ghc-7.6.3/include' '-D' '__GLASGOW_HASKELL__=706' '-D' 'linux_BUILD_OS=1' '-D' 's390x_BUILD_ARCH=1' '-D' 'linux_HOST_OS=1' '-D' 's390x_HOST_ARCH=1' '-include' 'compiler/stage1/build/autogen/cabal_macros.h' '-D' 'NO_REGS' '-D' 'STAGE=1' '-o' '/tmp/ghc36897_0/ghc36897_117.hscpp' '-march=z9-109' '-mtune=z10' '-m64' '-mzarch'
 /usr/libexec/gcc/s390x-redhat-linux/4.8.1/cc1 -E -traditional-cpp -quiet -v -I compiler/stage1/build -I compiler/stage1/build -I compiler/stage1/build/autogen -I compiler/stage1 -I compiler/. -I compiler/parser -I compiler/utils -I /usr/lib64/ghc-7.6.3/process-1.1.0.2/include -I /usr/lib64/ghc-7.6.3/old-time-1.1.0.1/include -I /usr/lib64/ghc-7.6.3/directory-1.2.0.1/include -I /usr/lib64/ghc-7.6.3/unix-2.6.0.1/include -I /usr/lib64/ghc-7.6.3/bytestring-0.10.0.2/include -I /usr/lib64/ghc-7.6.3/time-1.4.0.1/include -I /usr/lib64/ghc-7.6.3/base-4.6.0.1/include -I /usr/lib64/ghc-7.6.3/include -D __GLASGOW_HASKELL__=706 -D linux_BUILD_OS=1 -D s390x_BUILD_ARCH=1 -D linux_HOST_OS=1 -D s390x_HOST_ARCH=1 -D NO_REGS -D STAGE=1 -include compiler/stage1/build/autogen/cabal_macros.h /tmp/ghc36897_0/ghc36897_42.lpp -o /tmp/ghc36897_0/ghc36897_117.hscpp -march=z9-109 -mtune=z10 -m64 -mzarch -fno-stack-protector -undef
ignoring nonexistent directory "/usr/lib/gcc/s390x-redhat-linux/4.8.1/include-fixed"
ignoring nonexistent directory "/usr/lib/gcc/s390x-redhat-linux/4.8.1/../../../../s390x-redhat-linux/include"
ignoring duplicate directory "compiler/stage1/build"
#include "..." search starts here:
#include <...> search starts here:
 compiler/stage1/build
 compiler/stage1/build/autogen
 compiler/stage1
 compiler/.
 compiler/parser
 compiler/utils
 /usr/lib64/ghc-7.6.3/process-1.1.0.2/include


So far the hangs under the big command look random, which I also saw
when running it verbosely by hand, and so naively seems to
put more suspicion on gcc/cpp but really need to investigate further.

Created attachment 804724 [details]
ghc.spec-verbose-build.patch

Another datapoint: apparently "strace ghc -M -dep-makefile ..."  does not hang.
This could be some kind of process race-condition perhaps.

15692 pts/3    Ssl+   3:37              \_ /usr/lib64/ghc-7.6.3/ghc -B/usr/lib64/ghc-7.6.3 -optc-I/usr/include -v1 -M -dep-m
16531 pts/3    Z+     0:00                  \_ [gcc] <defunct>

AFAICT each hang happens after the preprocessed file has been output,
and running the individual preprocessing commands by hand seems not to hang so far.

(In reply to Jens Petersen from comment #15)
> Another datapoint: apparently "strace ghc -M -dep-makefile ..."  does not
> hang.
> This could be some kind of process race-condition perhaps.

sounds logical as the symptom I saw looked as a waiting loop that went wrong

> 15692 pts/3    Ssl+   3:37              \_ /usr/lib64/ghc-7.6.3/ghc
> -B/usr/lib64/ghc-7.6.3 -optc-I/usr/include -v1 -M -dep-m
> 16531 pts/3    Z+     0:00                  \_ [gcc] <defunct>
> 
> AFAICT each hang happens after the preprocessed file has been output,
> and running the individual preprocessing commands by hand seems not to hang
> so far.

Not a lot of info from the gdb backtrace

(gdb) bt
#0  0x00000080c6c31ad0 in .pthread_cond_wait () from /lib64/libpthread.so.0
#1  0x00000000136bd7d0 in ?? ()
#2  0x00000000136a75fc in ?? ()
#3  0x00000000136a2128 in ?? ()
#4  0x00000000136a38e8 in ?? ()
#5  0x00000000136a6004 in ?? ()
#6  0x00000000136b3524 in ?? ()
#7  0x00000000136b367c in ?? ()
#8  0x0000000010030b3c in ?? ()
#9  0x00000080c6a6482c in .generic_start_main.isra.0 () from /lib64/libc.so.6
#10 0x00000080c6a64a34 in .__libc_start_main () from /lib64/libc.so.6
#11 0x0000000000000000 in ?? ()

I tried debuginfo-install unsuccessfully (well there is no debuginfo for ghc).

You are probably hitting this glibc bug: https://bugzilla.redhat.com/show_bug.cgi?id=1007590

Thank you Gustavo for the valuable information.
Then I will wait for an glibc update or other news on this.

Okay I tried glibc-2.18-10.fc20.ppc64 but the ghc build still hung
in the same place as above.

for the record this strace output for the stuck ghc process with the old glibc on f20/s390x

...
futex(0x9106065c, FUTEX_WAIT_PRIVATE, 1289, NULL) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
--- SIGVTALRM {si_signo=SIGVTALRM, si_code=SI_TIMER, si_pid=0, si_uid=0, si_value=0} ---
sigreturn() (mask [])                   = 2433091164
futex(0x9106065c, FUTEX_WAIT_PRIVATE, 1289, NULL) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
--- SIGVTALRM {si_signo=SIGVTALRM, si_code=SI_TIMER, si_pid=0, si_uid=0, si_value=0} ---
sigreturn() (mask [])                   = 2433091164
futex(0x9106065c, FUTEX_WAIT_PRIVATE, 1289, NULL) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
--- SIGVTALRM {si_signo=SIGVTALRM, si_code=SI_TIMER, si_pid=0, si_uid=0, si_value=0} ---
sigreturn() (mask [])                   = 2433091164
futex(0x9106065c, FUTEX_WAIT_PRIVATE, 1289, NULL) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
--- SIGVTALRM {si_signo=SIGVTALRM, si_code=SI_TIMER, si_pid=0, si_uid=0, si_value=0} ---
sigreturn() (mask [])                   = 2433091164
futex(0x9106065c, FUTEX_WAIT_PRIVATE, 1289, NULL) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
--- SIGVTALRM {si_signo=SIGVTALRM, si_code=SI_TIMER, si_pid=0, si_uid=0, si_value=0} ---
sigreturn() (mask [])                   = 2433091164
futex(0x9106065c, FUTEX_WAIT_PRIVATE, 1289, NULL) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
--- SIGVTALRM {si_signo=SIGVTALRM, si_code=SI_TIMER, si_pid=0, si_uid=0, si_value=0} ---
sigreturn() (mask [])                   = 2433091164
futex(0x9106065c, FUTEX_WAIT_PRIVATE, 1289, NULL) = ? ERESTARTSYS (To be restarted if SA_RESTART is set)
--- SIGVTALRM {si_signo=SIGVTALRM, si_code=SI_TIMER, si_pid=0, si_uid=0, si_value=0} ---
sigreturn() (mask [])                   = 2433091164

and really the same symptoms with glibc-2.18-10.fc20.s390x installed

The futex syscall is being continuously interrupted by SIGVTALRM, which seems to be the cause.  Since you're stuck in pthread_cond_wait, I'd look at who is calling it and also who has registered that alarm, which is probably going off way too often.

ghc seems to have a tracing facility... have you tried enabling DEBUG_sched?

(In reply to Gustavo Luiz Duarte from comment #24)
> ghc seems to have a tracing facility... have you tried enabling DEBUG_sched?

I am not familiar with it: do you have any more info on it?

Looking through the ghc compiler driver code, it seems the exit
point from ghc to the process library related to the seen hangs
happens from compiler/main/SysTools.lhs.

runCpp or runUnlit -> runSomething -> builderMainLoop which is defined at:

http://git.haskell.org/ghc.git/blob/HEAD:/compiler/main/SysTools.lhs#l1014

and runs the process which a loop watches:

    -- status starts at zero, and increments each time either
    -- a reader process gets EOF, or the build proc exits.  We wait
    -- for all of these to happen (status==3).
    -- ToDo: we should really have a contingency plan in case any of
    -- the threads dies, such as a timeout.

Dunno if the last comment may be relevant to this bug...

Created attachment 816841 [details]
Fix infinite loop on 64 bits big endian platforms

I was able to build ghc with debug enabled, which gave me a sane stack trace that pointed where ghc is stuck.

I've attached a patch that fixes this issue. Notice that we will have to re-bootstrap ghc-7.6.3 using an older ghc in the buildroot (I tested using 7.4.2-11.1.fc19) to make sure we don't hit this issue during the build.

More details on this issue and the fix can be found on the upstream bug: http://ghc.haskell.org/trac/ghc/ticket/8134#comment:12

Thank you Gustavo this is really great.

I will start working on getting this into Rawhide and F20 particularly,
coordinating the the PPC and S390 port maintainers.

Gustavo, can you also attach a patch showing the changes you made
to ghc.spec or ghc to do the debug build?  That would be very useful
reference for the future if we should hit a similar problem again,
and anyway I would like to know how to do it.

(One good news is that the patch does not seem to affect the ABI hashes directly
at least on intel.)

I have committed the patch to ghc master and f20 branches.

This is the F21 (rawhide) commit (for ghc-7.6.3-19.fc21)
which can be used to rebootstrap ppc* and s390*:

commit bf23eb900bd28cfd861ddcbbe179b49e758fd56d
Date:   Tue Oct 29 14:59:08 2013 +0900

    bootstrap build to fix hangs on 64bit bigendian
    
    - rts hang patch from Gustavo Luiz Duarte (#989593)


Currently F20 bootstrap build (ghc-7.6.3-18.1.fc20) is building in main koji:
http://koji.fedoraproject.org/koji/buildinfo?buildID=474489

As Gustavo mentioned both need to be rebootstrapped against ghc-7.4.2
which should avoid the RTS channel hang being experienced
with current ghc-7.6.3 builds on bigendian 64bit archs.

(In reply to Jens Petersen from comment #31)
> commit bf23eb900bd28cfd861ddcbbe179b49e758fd56d
:
>     bootstrap build to fix hangs on 64bit bigendian
>     - rts hang patch from Gustavo Luiz Duarte (#989593)

The f21 scratch build is here btw:
http://koji.fedoraproject.org/koji/taskinfo?taskID=6110501

(In reply to Gustavo Luiz Duarte from comment #27)
> I was able to build ghc with debug enabled, which gave me a sane stack trace
> that pointed where ghc is stuck.

Ah maybe I should enable debuginfo for ghc builds since indeed
it contains some C code.

(In reply to Jens Petersen from comment #33)
> (In reply to Gustavo Luiz Duarte from comment #27)
> > I was able to build ghc with debug enabled, which gave me a sane stack trace
> > that pointed where ghc is stuck.
> 
> Ah maybe I should enable debuginfo for ghc builds since indeed
> it contains some C code.

Yeah, I believe enabling debuginfo for ghc would be a good idea.

Regardind the changes I've made to build ghc with debug enabled, I added the following to mk/build.mk:
EXTRA_HC_OPTS=-debug

Please notice this option enables several other checkings and logging facilities other than just debuginfo. See:
http://ghc.haskell.org/trac/ghc/wiki/Debugging/RuntimeSystem

(In reply to Gustavo Luiz Duarte from comment #34)
> Yeah, I believe enabling debuginfo for ghc would be a good idea.

Thanks yes I have enabled it in:

ghc-7.6.3-20.fc21: http://koji.fedoraproject.org/koji/buildinfo?buildID=474616
and
ghc-7.6.3-18.2.fc20: http://koji.fedoraproject.org/koji/buildinfo?buildID=474618

Fedora p-series and z-system guys: please use these builds to complete the re-bootstrapping of ghc-7.6.3.

> EXTRA_HC_OPTS=-debug

Thanks I will add it as a comment to ghc.spec.
I assume it is not good to build it into production RTS?


I see the F20 ppc and s390 bootstrap builds finished already:
http://ppc.koji.fedoraproject.org/koji/buildinfo?buildID=205255
http://s390.koji.fedoraproject.org/koji/buildinfo?buildID=217377

Thanks :)

ghc-7.6.3-18.2.fc20 has been submitted as an update for Fedora 20.
https://admin.fedoraproject.org/updates/ghc-7.6.3-18.2.fc20

ghc-7.6.3-18.2.fc20 is now built for s390*.
ghc-7.6.3-18.1.fc20 ppc* build is not tagged yet.

Package ghc-7.6.3-18.2.fc20:
* should fix your issue,
* was pushed to the Fedora 20 testing repository,
* should be available at your local mirror within two days.
Update it with:
# su -c 'yum update --enablerepo=updates-testing ghc-7.6.3-18.2.fc20'
as soon as you are able to.
Please go to the following url:
https://admin.fedoraproject.org/updates/FEDORA-2013-20306/ghc-7.6.3-18.2.fc20
then log in and leave karma (feedback).

ghc-7.6.3-18.2.fc20 ppc and s390 builds also now in f20-updates-testing.
Thanks guys!

ghc-7.6.3-18.2.fc20 has been pushed to the Fedora 20 stable repository.  If problems still persist, please make note of it in this bug report.