#8328: Crash at -O2: Cannot read from uninitialized register ----------------------------------+--------------------------------------- Reporter: bos | Owner: Type: bug | Status: new Priority: highest | Milestone: 7.8.1 Component: Compiler | Version: 7.7 Keywords: | Operating System: Linux Architecture: x86_64 (amd64) | Type of failure: Compile-time crash Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ----------------------------------+--------------------------------------- I did a quick x86_64 compile of all of Hackage today using HEAD, and GHC is crashing when compiling the utf8-string package. {{{ [2 of 7] Compiling Codec.Binary.UTF8.Generic ( Codec/Binary/UTF8/Generic.hs, dist/dist-sandbox- 4a6171fb/build/Codec/Binary/UTF8/Generic.o ) ghc: panic! (the 'impossible' happened) (GHC version 7.7.20130915 for x86_64-unknown-linux): allocateRegsAndSpill: Cannot read from uninitialized register %vI_sa0l }}} To reproduce using utf8-string: {{{ cabal get utf8-string cd utf8-string* ghc -XCPP -fforce-recomp -O2 --make -c Codec/Binary/UTF8/Generic.hs }}} -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8328 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler