[PATCH v3] c++: Add support for [[gnu::trivial_abi]] attribute [PR107187]

[Jason Merrill]

On 1/28/26 6:33 PM, Jakub Jelinek wrote:
> On Wed, Jan 28, 2026 at 06:28:04PM +0800, Jason Merrill wrote:
>>> There was also a suggestion that we accept the corresponding
>>> [[clang::trivial_abi]] spelling. I believe it can be done in a separate
>>> patch.
>>
>> It seems like when Clang adopts gnu:: attributes, they keep the gnu::
>> spelling; we might want to do the same for Clang attributes.  That is,
>> support clang::trivial_abi and not add gnu::trivial_abi.
> 
> Though, e.g. for musttail we just added [[gnu::musttail]] and support
> [[clang::musttail]] with the same meaning.

It seems to me that supporting gnu:: and clang:: with the same semantics 
just complicates code portability; if the goal is to handle existing 
code, that means supporting the existing spelling.

Jason