Re: [PING 2] [C PATCH] Synthesize nonnull attribute for parameters declared with static

[Jeff Law <jeffreyalaw@gmail.com>]

On 10/21/23 05:09, Martin Uecker wrote:
>>
>> C programmers increasingly use static to indicate that
>> pointer parameters are non-null.  Clang can exploit this
>> for warnings and optimizations.  GCC has some warnings
>> but not all warnings it has for nonnull.  Below is a
>> patch to add a nonnull attribute automatically for such
>> arguments and to remove the special and more limited
>> nonnull warnings for static. This patch found some
>> misplaced annotations in one of my projects via
>> -Wnonnull-compare which clang does not seem to have,
>> so I think this could be useful.
> 
>      c: Synthesize nonnull attribute for parameters declared with static [PR110815]
>      
>      Parameters declared with `static` are nonnull. We synthesize
>      an artifical nonnull attribute for such parameters to get the
>      same warnings and optimizations.
>      
>      Bootstrapped and regression tested on x86.
>      
> 	    PR c/102558
> 	    PR 102556
>              PR c/110815
>      
>      gcc/c-family:
>              * c-attribs.cc (build_attr_access_from_parms): Synthesize
>              nonnull attribute for parameters declared with `static`.
>      
>      gcc:
>              * gimple-ssa-warn-access.cc (pass_waccess::maybe_check_access_sizes):
>              remove warning for parameters declared with `static`.
>      
>      gcc/testsuite:
>              * gcc.dg/Wnonnull-8.c: Adapt test.
>              * gcc.dg/Wnonnull-9.c: New test.
This is OK -- assuming you did the usual bootstrap & regression test 
cycle.

Jeff