[Bug libgcc/71951] libgcc_s built with -fomit-frame-pointer on aarch64 is broken

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71951

--- Comment #6 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Timo Teräs from comment #5)
> Not easily. It's musl, and using iterate phdr. Same build script works on
> x86, x86_64 and armhf. It's only aarch64 misbehaving like this with omit
> frame pointer. Any other suggestions what to try/how to debug further?

So check the unwind information to see if it is correct.


   0x000003ffb7db974c <+20>:    sxtw    x1, w1
   0x000003ffb7db9750 <+24>:    ldr     x2, [x0,x1,lsl #3]

So x0 + ((long long)(int)w1) << 3
Or rather contex + index

And it is looking into x29 because of x1 is 29.

So it does look like the unwind information is messed up for the frame being
looked at.