[PATCH] fix bz #16169 - CFI directives missing from AArch64 clone.S

[Tom Tromey]

>>>>> "Ryan" == Ryan Arnold <ryan.arnold@linaro.org> writes:

Ryan> I finally got access to an environment where I could test this and
Ryan> came up with the same fix you did for cfi_undefined (x30).

Ryan> I ran a modified version of nptl/tst-align2 to hit the error syscall
Ryan> error path but wasn't able to get gdb to hang as Tom described either
Ryan> before or after the fix was applied.  I was using ni and bt while
Ryan> broken inside of __clone. Perhaps that's not how he hit the condition
Ryan> in the first place, but he'll have to elaborate.

The initial report was here:

    https://sourceware.org/bugzilla/show_bug.cgi?id=16155

You may need to try an older gdb to reproduce the problem; the bug
causing gdb to hang was fixed in a way that hides the missing CFI
problem here.  I still think it's correct to add these CFI directives,
though.

Tom