#12062: Parallel make with -j0 and hs-boot leads to floating point exception -------------------------------------+------------------------------------- Reporter: ezyang | Owner: Type: bug | Status: new Priority: low | Milestone: Component: Runtime | Version: 8.0.1-rc2 System | Keywords: newcomer | Operating System: Unknown/Multiple Architecture: | Type of failure: None/Unknown Unknown/Multiple | Test Case: | Blocked By: Blocking: | Related Tickets: Differential Rev(s): | Wiki Page: -------------------------------------+------------------------------------- When I run https://ghc.haskell.org/trac/ghc/ticket/1012#comment:5 with `ghc-8.0 --make ModuleB.hs -j0 -fforce-recomp` (the `-j0` is important) I get a `Floating point exception (core dumped)`. When I run under GDB, I get: {{{ (gdb) r Starting program: /srv/code/ghc-8.0.0.20160204/usr/lib/ghc-8.0.0.20160204/bin/ghc -B/home/ezyang/Dev/ghc-8.0.0.20160204/usr/lib/ghc-8.0.0.20160204 --make ModuleB.hs -j0 -fforce-recomp [Thread debugging using libthread_db enabled] Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1". [New Thread 0x7fffecd7f700 (LWP 28877)] [New Thread 0x7fffe7fff700 (LWP 28878)] [New Thread 0x7fffe77fe700 (LWP 28879)] [1 of 4] Compiling ModuleA[boot] ( ModuleA.hs-boot, ModuleA.o-boot ) [2 of 4] Compiling ModuleC ( ModuleC.hs, ModuleC.o ) [3 of 4] Compiling ModuleA ( ModuleA.hs, ModuleA.o ) [4 of 4] Compiling ModuleB ( ModuleB.hs, ModuleB.o ) Program received signal SIGFPE, Arithmetic exception. [Switching to Thread 0x7fffecd7f700 (LWP 28877)] schedule (initialCapability=<optimized out>, task=task@entry=0x7b6310) at rts/Schedule.c:373 373 rts/Schedule.c: No such file or directory. (gdb) bt #0 schedule (initialCapability=<optimized out>, task=task@entry=0x7b6310) at rts/Schedule.c:373 #1 0x00007fffed65018c in scheduleWorker (cap=<optimized out>, task=0x7b6310) at rts/Schedule.c:2378 #2 0x00007ffff738a6aa in start_thread (arg=0x7fffecd7f700) at pthread_create.c:333 #3 0x00007fffed14fe9d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109 }}} I once got a different error running this: {{{ warning: Corrupted shared library list: 0x7e1ee0 != 0x7ffff7ffd9d8 }}} Looking at the code which is a `capabilities[cap->no % enabled_capabilities]`, I guess this is just something goofy, like GHC not rejecting `-j0` and then however we're setting the capabilities not checking this case. -- Ticket URL: http://ghc.haskell.org/trac/ghc/ticket/12062 GHC http://www.haskell.org/ghc/ The Glasgow Haskell Compiler