Re: [PATCH 01/12] kbuild: make -Woverride-init warnings more consistent

[Arnd Bergmann]

On Tue, Mar 26, 2024, at 21:24, Jani Nikula wrote:
> On Tue, 26 Mar 2024, Arnd Bergmann <arnd@xxxxxxxxxx> wrote:
>> From: Arnd Bergmann <arnd@xxxxxxxx>
>> index 475e1e8c1d35..0786eb0da391 100644
>> --- a/drivers/net/ethernet/renesas/sh_eth.c
>> +++ b/drivers/net/ethernet/renesas/sh_eth.c
>> @@ -50,7 +50,7 @@
>>   * the macros available to do this only define GCC 8.
>>   */
>>  __diag_push();
>> -__diag_ignore(GCC, 8, "-Woverride-init",
>> +__diag_ignore_all("-Woverride-init",
>>  	      "logic to initialize all and then override some is OK");
>
> This is nice because it's more localized than the per-file
> disable. However, we tried to do this in i915, but this doesn't work for
> GCC versions < 8, and some defconfigs enabling -Werror forced us to
> revert. See commit 290d16104575 ("Revert "drm/i915: use localized
> __diag_ignore_all() instead of per file"").

It works now.

The original __diag_ignore_all() only did it for gcc-8 and above
because that was initially needed to suppress warnings that
got added in that version, but this was always a mistake.

689b097a06ba ("compiler-gcc: Suppress -Wmissing-prototypes
warning for all supported GCC") made it work correctly.

     Arnd