Created attachment 382364 [details, diff] gcc 4.9.0 patch from upstream Linus colourfully describes how gcc 4.9.0 and the compiler versions 4.5.0 (when debug_insn came in) to 4.8.3 and 4.9.0 and 4.9.1 generate incorrect code with -g leading to random kernel crashes: http://lkml.iu.edu/hypermail/linux/kernel/1407.3/00650.html The gcc bug report including the fix: Bug 61801 - sched2 miscompiles syscall sequence with -g https://gcc.gnu.org/bugzilla/show_bug.cgi?id=61801 The attached patch contains the fix from upstream: https://gcc.gnu.org/viewcvs/gcc/branches/gcc-4_9-branch/gcc/sched-deps.c?r1=209304&r2=212739&pathrev=212739
Fixed in 4.9.1 p1.0 so far.
(In reply to Ryan Hill from comment #1) > Fixed in 4.9.1 p1.0 so far. This fix is now in 4.9.2 and we no longer need patch/91_all_4.9.2_pr61801.patch. See bug #527480. If someone wants to produce the new 4.9.2 patchset.
this is fixed in Gentoo's gcc-4.9.1 already