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From: "eggert at cs dot ucla.edu" <gcc-bugzilla@gcc.gnu.org>
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Subject: [Bug c/44677] Warn for variables incremented but not used
Date: Sat, 09 Apr 2022 00:48:33 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D44677

eggert at cs dot ucla.edu changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |eggert at cs dot ucla.edu

--- Comment #13 from eggert at cs dot ucla.edu ---
I ran into this issue today on Emacs master, with both +=3D and |=3D. Clang
correctly diagnosed unused local variables, but GCC did not.

It would be nice if GCC could do at least as well as Clang does.

Here are references to patches I installed into Emacs to fix these issues t=
hat
Clang found but GCC did not:

https://git.savannah.gnu.org/cgit/emacs.git/commit/?id=3Dd9bffa1f3b121085fd=
8f954eb9446a4a5241c062
https://git.savannah.gnu.org/cgit/emacs.git/commit/?id=3D68bc1446855c86b96d=
5bc22f819e63358ab250ac=