[PATCH] D21222: Double size of sigaltstack to prevent overflow

Thu Jun 30 00:56:30 PDT 2016

Hahnfeld added a comment.

In http://reviews.llvm.org/D21222#470596, @bcahoon wrote:

> I'm seeing the same problem, which is fixed with this patch.  I'm seeing a hang when running llvm-lit with test/Bugpoint/crash-narrowfunctiontest.ll. The hang appears to be caused because data in the stack frame is corrupted, and the clear() method in a vector never returns, when executing CallBacksToRun->clear() in RunSignalHandlers().
>
> This happens only when I build llvm in Debug mode. In Release mode, the problem doesn't occur.  Also, if I build llvm in Debug mode, but compile only Signals.cpp with -O3, the failure doesn't occur.
>
> I'm not sure how much stack space is needed on the alternate stack, though I tried MINSIGSTKSZ + 11264 and that works for me.

Yes, exactly. @rsmith is this ok to commit?

http://reviews.llvm.org/D21222