#11978: running a profiled build of shake test suite with rts args +RTS -hb -N10 triggers SIGSEGV ---------------------------------+---------------------------------------- Reporter: carter | Owner: Type: bug | Status: patch Priority: highest | Milestone: Component: Compiler | Version: 8.0.1 Resolution: | Keywords: Operating System: MacOS X | Architecture: Unknown/Multiple Type of failure: None/Unknown | Test Case: Blocked By: | Blocking: Related Tickets: #4820 | Differential Rev(s): phab:D2159 Wiki Page: | ---------------------------------+---------------------------------------- Comment (by erikd): On IRC @simonmar said that in this function `overwritingClosure` the closure type should not be `WHITEHOLE`. The backtrace looks like: {{{ Program received signal SIGSEGV, Segmentation fault. [Switching to Thread 0x7fffca7fc700 (LWP 27422)] executeMessage (cap=cap@entry=0x14861a0, m=0x20022b340) at rts/Messages.c:104 104 doneWithMsgThrowTo(t); (gdb) bt #0 executeMessage (cap=cap@entry=0x14861a0, m=0x20022b340) at rts/Messages.c:104 #1 0x0000000000f47834 in scheduleProcessInbox (pcap=<optimized out>) at rts/Schedule.c:1005 #2 scheduleFindWork (pcap=<optimized out>) at rts/Schedule.c:616 #3 schedule (initialCapability=<optimized out>, task=task@entry=0x7fffc4000910) at rts/Schedule.c:274 #4 0x0000000000f490dc in scheduleWorker (cap=<optimized out>, task=0x7fffc4000910) at rts/Schedule.c:2382 #5 0x00007ffff75b6454 in start_thread (arg=0x7fffca7fc700) at pthread_create.c:334 #6 0x00007ffff6d72eed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109 }}} The call path seems to be `scheduleProcessInbox` gets the next message, passes it to `executeMessage` which calls `throwToMsg` on it which returns `THROWTO_SUCCESS`, and then passes the message to `doneWithMsgThrowTo` which then passes it to `overwritingClosure`. Reading @ezyang's paper http://ezyang.com/jfp-ghc-rts-draft.pdf suggests that yes indeed this code path should not be executed when the closure type is `WHITEHOLE`. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/11978#comment:14 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler