Test suite failures with GCC 11 in header checks

[Siddhesh Poyarekar]

On 2023-07-20 07:05, Adhemerval Zanella Netto via Libc-alpha wrote:
> I will check this today, another option would to just use maximum level of '2'
> for now.
> 

Yeah, that ought to be sufficient for installed header tests.

Thanks,
Sid