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From: Richard Biener <richard.guenther@gmail.com>
Date: Fri, 28 Jan 2022 13:15:49 +0100
Message-ID: <CAFiYyc07CMJt8bbartX5bVP9cykjVkzcyKjfgr-jEGhG3LKQyA@mail.gmail.com>
Subject: Re: [PATCH] constrain PHI handling in -Wuse-after-free (PR104232)
To: Martin Sebor <msebor@gmail.com>
Cc: gcc-patches <gcc-patches@gcc.gnu.org>
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On Thu, Jan 27, 2022 at 7:58 PM Martin Sebor via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> The indiscriminate PHI handling by -Wuse-after-free has caused
> the false positive reported in PR 104232.  The attached patch
> refines the handling to only consider PHIs all of whose operands
> refer to the same object and disregard the rest.
>
> Tested on x86_64-linux and by compiling a few toolchain projects,
> including Glibc and Binutils/GDB, to verify the absence of false
> positives.

OK.

> Martin