Re: [PATCH v2] c: Add -Wreturn-mismatch warning, split from -Wreturn-type

[Florian Weimer <fweimer@redhat.com>]

* Florian Weimer:

> The existing -Wreturn-type option covers both constraint violations
> (which are mandatory to diagnose) and warnings that have known
> false positives.  The new -Wreturn-mismatch warning is only about
> the constraint violations (missing or extra return expressions),
> and should eventually be turned into a permerror.
>
> The -std=gnu89 test cases show that by default, we do not warn for
> return; in a function not returning void.  This matches previous
> practice for -Wreturn-type.
>
> gcc/c-family/
>
> 	* c.opt (Wreturn-mismatch): New.
>
> gcc/c/
>
> 	* c-typeck.cc (c_finish_return): Use pedwarn with
> 	OPT_Wreturn_mismatch for missing/extra return expressions.
>
> gcc/
>
> 	* doc/invoke.texi (Warning Options): Document
> 	-Wreturn-mismatch.  Update -Wreturn-type documentation.
>
> gcc/testsuite/
>
> 	* gcc.dg/Wreturn-mismatch-1.c: New.
> 	* gcc.dg/Wreturn-mismatch-2.c: New.
> 	* gcc.dg/Wreturn-mismatch-3.c: New.
> 	* gcc.dg/Wreturn-mismatch-4.c: New.
> 	* gcc.dg/Wreturn-mismatch-5.c: New.
> 	* gcc.dg/Wreturn-mismatch-6.c: New.
> 	* gcc.dg/noncompile/pr55976-1.c: Change -Werror=return-type
> 	to -Werror=return-mismatch.
> 	* gcc.dg/noncompile/pr55976-2.c: Likewise.
>
> ---
> v2: Update comment in gcc.dg/noncompile/pr55976-2.c.  Do not produce
>     an error in C90 pedantic-error mode for return; in a function
>     returning non-void.  Add gcc.dg/Wreturn-mismatch-6.c to demonstrate
>     this behavior.

Ping?  Original patch:

<https://inbox.sourceware.org/gcc-patches/8734y523et.fsf@oldenburg.str.redhat.com/>

Thanks,
Florian