Re: [PATCH bpf] selftests/bpf: fix backtrace printing for selftests crashes

[Tony Ambardar <tony.ambardar@gmail.com>]

On Thu, Oct 03, 2024 at 02:07:23PM -0700, Eduard Zingerman wrote:
> On Thu, 2024-10-03 at 14:03 -0700, Eduard Zingerman wrote:
> 
> [...]
> 
> > Resolve this by hiding stub definitions behind __GLIBC__ macro check
> > instead of using "weak" attribute.
> > 
> > Fixes: c9a83e76b5a9 ("selftests/bpf: Fix compile if backtrace support missing in libc")
> 
> Hi Tony,
> 
> could you please double-check if your musl setup behaves as expected
> after these changes?
> 

Hi Eduard,

I discovered building for musl has broken over the last month or so, and
it took some time to find fixes and workarounds before I could retest.

Since glibc execinfo.h also defines its functions as weak, and given the
linking issues that can cause, I think changing the #ifdef as you did is
the right approach. But could you leave the fallback stub functions as
"__weak" like before to simplify overriding in the non-GLIBC case?

Otherwise:

Reviewed-by: Tony Ambardar <tony.ambardar@gmail.com>
Tested-by: Tony Ambardar <tony.ambardar@gmail.com>

Thanks,
Tony

> Thanks,
> Eduard
>