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In-Reply-To: <20230130230959.GW25951@gate.crashing.org>
From: Patrick Herbst <paherbst@gmail.com>
Date: Mon, 30 Jan 2023 18:16:37 -0500
Message-ID: <CACMdL5+KmADNhOKyHkTh1cSxL4pkKc=QCdmRMRRnZqJmN2m4OQ@mail.gmail.com>
Subject: Re: how does -Wstringop-truncation work?
To: Segher Boessenkool <segher@kernel.crashing.org>
Cc: gcc-help <gcc-help@gcc.gnu.org>
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On Mon, Jan 30, 2023 at 6:12 PM Segher Boessenkool
<segher@kernel.crashing.org> wrote:
>
> The manual says
>   The effectiveness of some warnings depends on optimizations also being
>   enabled.  For example '-Wsuggest-final-types' is more effective with
>   link-time optimization and some instances of other warnings may not be
>   issued at all unless optimization is enabled.  While optimization in
>   general improves the efficacy of control and data flow sensitive
>   warnings, in some cases it may also cause false positives.
>
>
> Flags like -O1 do more than just enabling some other flags.
>

Thank you!
Another point of clarification; how is it that -foptimize-strlen is
necessary for -Wstringop-truncation to work?  Is that noted somewhere?