Fix tail call optimisation in C++ backtrace capture

[bamx23]

According to documentation there's a __attribute__((disable_tail_calls)) attribute that should work fine for our case where we need to make sure the stacktrace has predictable number of calls at the top.

[GLinnik21]

It looks great! But I would make sure that this attribute is not ignored and the frames really remain.

[naftaly]

fwiw, __asm__ __volatile__(""); should also force no tail call optimization.

[GLinnik21]

fwiw, __asm__ __volatile__(""); should also force no tail call optimization.

The question is which of these codes is more portable across different compilers?

[naftaly]

definitely the attribute if it works.

__asm__ __volatile__("");

Hard to say really. I'd expect an attribute like that to be my first choice, but the code I shared is what I found Apple does/was-doing in CF.

[bamx23]

I really like the idea with __asm__ __volatile__("");. Having both this and the attribute should not harm. Thanks @naftaly!

[bamx23]

Tested this PR:

	Static Lib	Dynamic Lib
Before
After

See that after the fix there's an extra frame in the stacktrace.
cc @GLinnik21

[GLinnik21]

See that after the fix there's an extra frame in the stacktrace.
cc @GLinnik21

Did the frame always get deleted before this fix?

[bamx23]

See that after the fix there's an extra frame in the stacktrace.
cc @GLinnik21

Did the frame always get deleted before this fix?

Yes (with Release build)

[GLinnik21]

Great! Thank you very much!