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From: "jakub at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c++/98151] integer output gives different results with -O2 and
 -O3
Date: Sat, 05 Dec 2020 09:21:54 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D98151

Jakub Jelinek <jakub at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|WAITING                     |RESOLVED
         Resolution|---                         |INVALID
                 CC|                            |jakub at gcc dot gnu.org

--- Comment #3 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
There is another UB in it, if you try to parse the INT_MIN value there is
another signed integer overflow, because 0x80000000 is not representable in
int, while -0x7fffffff-1 is.
Better to compute the result in unsigned type and only at the end cast to i=
nt.=