#8982: Heap profile restricted by biography of GHC segfaults ----------------------------------+---------------------------------- Reporter: ezyang | Owner: Type: bug | Status: new Priority: normal | Milestone: Component: Profiling | Version: 7.8.1 Keywords: | Operating System: Linux Architecture: x86_64 (amd64) | Type of failure: Runtime crash Difficulty: Unknown | Test Case: Blocked By: | Blocking: Related Tickets: | ----------------------------------+---------------------------------- Steps to reproduce: 1. Build GHC with profiling on 64-bit Linux 2. Run T1969 with RTS options -hc -hbvoid {{{ [ezyang@hs01 compiler]$ '/home/hs01/ezyang/ghc-compalloc/inplace/bin/ghc- stage2' -fforce-recomp -dno-debug-output -no-user-package-db -rtsopts -fno-ghci-history -c T1969.hs +RTS -V0 -tT1969.comp.stats --machine- readable -RTS -dcore-lint -static +RTS -hc -hbvoid Segmentation fault }}} Interestingly enough, I don't see the problem with other types of profiling, e.g. '-hd'. I tried a few simpler, nontrivial Haskell programs but I couldn't reproduce the segfault, so this is some sort of bug that only shows up in complex setting (maybe multithreading is the issue?) It reproduces quite reliably for me. When I build the runtime system with debugging, I get a useful assert failure: {{{ ghc-stage2: internal error: ASSERTION FAILED: file rts/ProfHeap.c, line 201 (GHC version 7.8.0.20140408 for x86_64_unknown_linux) Please report this as a GHC bug: http://www.haskell.org/ghc/reportabug }}} This assert is complaining that the cost center (CCS_SYSTEM) never made it into the hash table for era 149. I'll try looking for a simpler test-case later, but maybe someone can figure out what this bug is by sight. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/8982 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler