RE: [PATCH v2] x86: fix early boot crash on gcc-10
From: David Laight
Date: Sat Apr 18 2020 - 09:12:17 EST
From: Peter Zijlstra
> Sent: 17 April 2020 11:38
>
> On Fri, Apr 17, 2020 at 10:58:59AM +0200, Jakub Jelinek wrote:
> > Or go with the for (;;);, I don't think any compiler optimizes those away;
> > GCC 10 for C++ can optimize away infinite loops that have some conditional
> > exit because the language guarantees forward progress, but the C language
> > rules are different and for unconditional infinite loops GCC doesn't
> > optimize them away even if explicitly asked to -ffinite-loops.
>
> 'Funnily' there are people building the kernel with C++ :/
Can't you 'make progress' by using longjmp() to exit a signal handler?
David
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