glibc2.32 build error for powerpc64-unknown-linux-gnu

[Adhemerval Zanella]

On 30/08/2020 07:40, Chris Packham via Libc-help wrote:
> Hi,
> 
> crosstool-ng was recently updated to add glibc-2.32. We're seeing the 
> following error building for powerpc64
> 
> [ALL  ]      In file included from 
> ../sysdeps/powerpc/powerpc32/power4/multiarch/wordcopy-ppc32.c:26,
> [ALL  ]                       from 
> ../sysdeps/powerpc/powerpc64/multiarch/wordcopy-ppc64.c:18:
> [ALL  ]      ../string/wordcopy.c: In function '_wordcopy_fwd_aligned':
> [ERROR]      ../string/wordcopy.c:98:26: error: 'a1' may be used 
> uninitialized in this function [-Werror=maybe-uninitialized]
> [ALL  ]         98 |       ((op_t *) dstp)[0] = a1;
> [ALL  ]            |       ~~~~~~~~~~~~~~~~~~~^~~~
> 
> Looking at the code in question I think it's a spurious warning. There 
> even appears to be an attempt to turn off the warning in 
> sysdeps/generic/Makefile but the file is #included for powerpc so the 
> flags applied.
> 
> Bug report with full logs 
> https://github.com/crosstool-ng/crosstool-ng/issues/1380
> 

I haven't see it with gcc version 9.3.1, so it might be something related
to gcc 10 or newer.  I will build a gcc 10 and check if I can reproduce it.