Re: [PATCH] attribs: Implement -Wno-attributes=vendor::attr [PR101940]

[Jakub Jelinek <jakub@redhat.com>]

On Mon, Sep 20, 2021 at 01:06:58PM -0400, Marek Polacek via Gcc-patches wrote:

Not a review, just a few nits:

I think it would be useful to clarify that -Wno-attributes=list doesn't
actually imply -Wno-attributes

> --- a/gcc/common.opt
> +++ b/gcc/common.opt
> @@ -88,6 +88,9 @@ void *flag_instrument_functions_exclude_functions
>  Variable
>  void *flag_instrument_functions_exclude_files
>  
> +Variable
> +void *flag_ignored_attributes
> +
>  ; Generic structs (e.g. templates not explicitly specialized)
>  ; may not have a compilation unit associated with them, and so
>  ; may need to be treated differently from ordinary structs.
> @@ -546,6 +549,10 @@ Wattributes
>  Common Var(warn_attributes) Init(1) Warning
>  Warn about inappropriate attribute usage.
>  
> +Wattributes=
> +Common Joined
> +Do not warn about specified attributes.
> +

So, wouldn't be this better specified as
Wno-attributes=
Common Joined RejectNegative
(not sure if RejectNegative is actually needed for an option
starting with Wno- )?

> +/* { dg-additional-options "-std=c++11" { target c++ } } */
> +/* { dg-additional-options "-Wno-attributes=company::,yoyodyne::attr" } */
> +/* { dg-additional-options "-Wno-attributes=c1::attr,c1::attr,c1::__attr__" } */
> +/* { dg-additional-options "-Wno-attributes=clang" } */
> +/* { dg-additional-options "-Wno-attributes=c2::,c2::attr" } */
> +/* { dg-additional-options "-Wno-attributes=c3::attr,c3::" } */
> +/* { dg-additional-options "-Wno-attributes=x::," } */

Should the above be accepted (I mean trailing , ?)  What does that mean?

> +/* { dg-additional-options "-Wno-attributes=yoyodyne::attr_new" } */
> +/* { dg-additional-options "-Wno-attributes=c4::__attr__" } */

When writing __attr__, does that imply we won't warn about both
c4::attr and c4::__attr__ (and __c4__::attr and __c4__::__attr__) like
it would when writing -Wno-attributes=c4::attr ?

	Jakub