Pulled from #2176.
On x86-64 the SA_SIGINFO sa_flag is actually a no-op. It is always used
even if not set.
Ensure that we setup siginfo_t regardless of flag being set.
On 32-bit x86 this still needs to be adhered to.
Little side bits that don't change anything
- EFLAGS is passed in signfo correctly.
- User provided restorer usage locations is documented but not
implemented.
Ryan Houdek
7897803753