[crac] RFR: Support -XX:CPUFeatures=ignore during -XX:CRaCRestoreFrom

[Anton Kozlov]

On Wed, 9 Aug 2023 13:55:30 GMT, Jan Kratochvil <jkratochvil at openjdk.org> wrote:

> Support -XX:CPUFeatures=ignore during -XX:CRaCRestoreFrom

src/hotspot/cpu/x86/vm_version_x86.cpp line 1219:

> 1217:   }
> 1218:   return !*a && !*b;
> 1219: }

Compiler can inline a call to strcmp if it recognizes the pattern, so this is not really safe. And since we are calling the argument check after VM_Crac::read_shm, it's a bit late to worry about libc... It may be just fine to leave the one who are give up the safety with possible crashes.

-------------

PR Review Comment: https://git.openjdk.org/crac/pull/100#discussion_r1289132860