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From: "fxue at os dot amperecomputing.com" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug bootstrap/102681] [12 Regression] AArch64 bootstrap failure
Date: Thu, 14 Oct 2021 07:00:47 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D102681

--- Comment #4 from Feng Xue <fxue at os dot amperecomputing.com> ---
(In reply to Martin Sebor from comment #3)
> Simply initializing the variable as in the patch below avoids the warning=
.=20
> The control flow in the code is sufficiently opaque to make it worthwhile
> from a readability point irrespective of whether or not the variable can,=
 in
> fact, be used uninitialized.
>=20
> index e50d3fc3b62..c7f0a405ff6 100644
> --- a/gcc/calls.c
> +++ b/gcc/calls.c
> @@ -199,7 +199,7 @@ stack_region_maybe_used_p (poly_uint64 lower_bound,
> poly_uint64 upper_bound,
>  static void
>  mark_stack_region_used (poly_uint64 lower_bound, poly_uint64 upper_bound)
>  {
> -  unsigned HOST_WIDE_INT const_lower, const_upper;
> +  unsigned HOST_WIDE_INT const_lower, const_upper =3D 0;
>    const_lower =3D constant_lower_bound (lower_bound);
>    if (upper_bound.is_constant (&const_upper))
>      for (unsigned HOST_WIDE_INT i =3D const_lower; i < const_upper; ++i)

This code looks good, the warning seems to be an over-kill.
Will this change be checked in as a fix?=