bt #0 0x00000000007c8370 in stg_IND_STATIC_info () at rts/StgMiscClosures.cmm:270 #1 0x00000000006ae1f0 in bytestringzm0zi10zi8zi2_DataziByteStringziLazzy_fromChunkszugo_info () at
#15544: Non-deterministic segmentation fault in cryptohash-sha256 testsuite -------------------------------------+------------------------------------- Reporter: bgamari | Owner: (none) Type: bug | Status: new Priority: highest | Milestone: 8.6.1 Component: Compiler | Version: 8.4.3 Resolution: | Keywords: Operating System: Unknown/Multiple | Architecture: | Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | Differential Rev(s): Wiki Page: | -------------------------------------+------------------------------------- Comment (by bgamari): The previous debugging session ended up looking a bit messy. Starting afresh, this time with `+RTS -DS`. Things are looking much clearer now. We get the following segfault: {{{ Thread 2 received signal SIGSEGV, Segmentation fault. 0x00000000007c8370 in stg_IND_STATIC_info () at rts/StgMiscClosures.cmm:270 270 { libraries/bytestring/Data/ByteString/Lazy.hs:267 #2 0x00000000007c5388 in ?? () at rts/Updates.cmm:31 #3 0x00000000006adc50 in bytestringzm0zi10zi8zi2_DataziByteStringziLazzy_toChunkszugo_info () at libraries/bytestring/Data/ByteString/Lazy.hs:271 #4 0x00000000007c5388 in ?? () at rts/Updates.cmm:31 #5 0x0000000000624d20 in s7zn_info () #6 0x0000000000000000 in ?? () }}} where `$rbx` points to memory cleared by the RTS: {{{
x/8a $rbx 0x4200365960: 0xaaaaaaaaaaaaaaaa 0xaaaaaaaaaaaaaaaa 0x4200365970: 0xaaaaaaaaaaaaaaaa 0xaaaaaaaaaaaaaaaa 0x4200365980: 0xaaaaaaaaaaaaaaaa 0xaaaaaaaaaaaaaaaa 0x4200365990: 0xaaaaaaaaaaaaaaaa 0xaaaaaaaaaaaaaaaa }}} Tracing this back it looks like this once resided in a nursery that has since been freed. It sounds like something is being freed too soon (perhaps something like #14346/#15260). Looking at the package implementation it looks like there are a few `withForeignPtr` uses. This is quite suspicious.
-- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/15544#comment:7 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler