avx512erintrin.h: uninitialized variable warning (optimized build)

[Sam James]

> On 12 Jan 2023, at 00:26, James Addison via Gcc <gcc@gcc.gnu.org> wrote:
> 
> Hi,
> 
> During GCC 12.2.0 compilation of a file that includes[1] immintrin.h
> with both code-optimization and uninitialized-variable-warnings
> enabled, a warning is emitted:
> 
>    /usr/lib/gcc/x86_64-linux-gnu/12/include/avx512erintrin.h:55:20:
> warning: ‘__W’ is used uninitialized [-Wuninitialized]
> 
> The minimal repro compilation command appears to be:
> 
>    gcc -O -Wuninitialized -mavx512er -mavx512pf
> ./numpy/distutils/checks/cpu_avx512_knl.c
> 
> My question is: does the warning indicate a possible bug that should
> be reported, or is there a reason that the relevant code[2] does not
> initialize the variable (for example, for performance reasons)?

See also https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105593, might
be the same thing?
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