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From: "vincent-gcc at vinc17 dot net" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/109979] -Wformat-overflow false positive for %d and non-basic
 expression
Date: Fri, 26 May 2023 07:54:48 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D109979

--- Comment #5 from Vincent Lef=C3=A8vre <vincent-gcc at vinc17 dot net> ---
(In reply to Andrew Pinski from comment #1)
> The warning should happen for both ...

OK (as the documentation says "[...] that might overflow the destination
buffer).

(In reply to Richard Biener from comment #4)
> If you know the value is in a range that fits s[4] then assert that before
> the prints.

I don't think that an assert() will change anything. With MPFR, the code is=
 in
an "else" branch, already with a reduced range. However, this time, I did n=
ot
use -O2 to enable VRP (I was working on a different issue, but had to use
-Werror=3Dformat to change the behavior of the configure script); that was =
my
mistake. Then I found the inconsistency between "e" and "e - 1", so I did n=
ot
look further.=