Is anyone able to help me here? I have no idea how to hunt down a seg-fault in ghc-stage1.exe on Windows. I thought of using git bisect to try to find the offending commit (though each bisection takes a couple of hours since it has to be a clean build). But I was defeated by the fact that haddock is a separate repo, and the task of finding the haddock commit that matches the ghc commit defeated me. There are probably other repos too, but they probably change less often. In short, I'm stuck. I can use Linux at work, but when I'm on the move I just have my Windows laptop. What is frustrating is that GHC used to build on Windows just fine. Does anyone feel more competent than me feel able to bisect their way to the offending commit? Thanks Simon From: ghc-devs [mailto:ghc-devs-bounces@haskell.org] On Behalf Of Simon Peyton Jones Sent: 06 March 2014 23:42 To: ghc-devs@haskell.org Subject: RE: new Windows build problem Actually, the two problems seem to be the same. A fresh build from scratch yields libraries/random/ghc.mk:5: recipe for target 'libraries/random/dist-install/build/System/Random.o' failed make[1]: *** [libraries/random/dist-install/build/System/Random.o] Segmentation fault Then sniping the command line that tried to build Random.o yields "inplace/bin/ghc-stage2.exe" -hisuf hi -osuf o -hcsuf hc -static -H32m -O -Werror -Wall -H64m -O0 -package-name random-1.0.1.1 -hide-all-packages -i -ilibraries/random/. -ilibraries/random/dist-install/build -ilibraries/random/dist-install/build/autogen -Ilibraries/random/dist-install/build -Ilibraries/random/dist-install/build/autogen -Ilibraries/random/. -optP-include -optPlibraries/random/dist-install/build/autogen/cabal_macros.h -package base-4.7.0.0 -package time-1.4.2 -O2 -XHaskell98 -XCPP -O2 -O -dcore-lint -fno-warn-amp -fno-warn-deprecated-flags -dcore-lint -no-user-package-db -rtsopts -odir libraries/random/dist-install/build -hidir libraries/random/dist-install/build -stubdir libraries/random/dist-install/build -c libraries/random/./System/Random.hs -o libraries/random/dist-install/build/System/Random.o bash: [6536: 1 (255)] tcsetattr: Inappropriate ioctl for device io So this ioctl thing seems to be reported as a seg fault by the make system. Running the same command from a 'cmd' window does give a seg-fault pop-up window. Alas. Running with -dshow-passes shows that it happens during code generation, *** CorePrep: Result size of CorePrep = {terms: 1,214, types: 912, coercions: 52} *** Core Linted result of CorePrep: *** Stg2Stg: *** CodeOutput: *** New CodeGen: *** CPSZ: *** CPSZ: I am totally stuck. Simon From: Simon Peyton Jones Sent: 06 March 2014 22:11 To: ghc-devs@haskell.orgmailto:ghc-devs@haskell.org Subject: new Windows build problem Sigh. Totally new problem with building GHC (HEAD) on Windows.. "inplace/bin/ghc-stage2.exe" -hisuf hi -osuf o -hcsuf hc -static -H32m -O -Werror -Wall -H64m -O0 -package-name haskell98-2.0.0.3 -hide-all-packages -i -ilibraries/haskell98/. -ilibraries/haskell98/dist-install/build -ilibraries/haskell98/dist-install/build/autogen -Ilibraries/haskell98/dist-install/build -Ilibraries/haskell98/dist-install/build/autogen -Ilibraries/haskell98/. -optP-include -optPlibraries/haskell98/dist-install/build/autogen/cabal_macros.h -package array-0.5.0.0 -package base-4.7.0.0 -package directory-1.2.0.2 -package old-locale-1.0.0.6 -package old-time-1.1.0.2 -package process-1.2.0.0 -package time-1.4.2 -Wall -XHaskell98 -O2 -O -dcore-lint -fno-warn-amp -fno-warn-deprecated-flags -dcore-lint -no-user-package-db -rtsopts -odir libraries/haskell98/dist-install/build -hidir libraries/haskell98/dist-install/build -stubdir libraries/haskell98/dist-install/build -c libraries/haskell98/./Directory.hs -o libraries/haskell98/dist-install/build/Directory.o bash: [6536: 1 (255)] tcsetattr: Inappropriate ioctl for device HEAD $ What on earth is this ioctl stuff? The above is repeatable; same command line, same result. But I'm also getting random seg-faults when building libraries with the stage2 compiler libraries/random/ghc.mk:5: recipe for target 'libraries/random/dist-install/build/System/Random.o' failed make[1]: *** [libraries/random/dist-install/build/System/Random.o] Segmentation fault This is NOT repeatable. Saying 'make' again gets further. Any ideas? Simon