#14905: GHCi segfaults with +RTS -Di after hitting a breakpoint -------------------------------------+------------------------------------- Reporter: osa1 | Owner: (none) Type: bug | Status: new Priority: normal | Milestone: Component: GHCi | Version: 8.5 Keywords: | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- Steps to reproduce: - Compile stage2 with `-debug` - Run GHCi with `+RTS -Di` - Load an interpreted module with a definition, set a breakpoint on the definition - Evaluate the definition GHCi crashes with a segfault. Backtrace: {{{ #0 0x00007ffff18bcaa9 in disInstr (bco=0x4200013f30, pc=1) at rts/Disassembler.c:71 #1 0x00007ffff18c89e9 in interpretBCO (cap=0x7ffff19431c0 <MainCapability>) at rts/Interpreter.c:986 #2 0x00007ffff18d19fe in schedule (initialCapability=0x7ffff19431c0 <MainCapability>, task=0x7fffe0000910) at rts/Schedule.c:471 #3 0x00007ffff18d4ee2 in scheduleWorker (cap=0x7ffff19431c0 <MainCapability>, task=0x7fffe0000910) at rts/Schedule.c:2553 #4 0x00007ffff18ccab8 in workerStart (task=0x7fffe0000910) at rts/Task.c:444 #5 0x00007ffff0c3c6ba in start_thread (arg=0x7fffee9aa700) at pthread_create.c:333 #6 0x00007ffff06f241d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109 }}} in this line: {{{ 71 debugBelch(" %s\n", ((CostCentre*)(literals[instrs[pc+3]]))->label); }}} `literals[instrs[pc+3]]` is null. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/14905 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler