On 07.07.25 17:41, Corentin via Core wrote:
> Hey folks,
>
> [[foo(#)]] is a valid attribute in C, but invalid in C++, as # is considered a token in C and a preprocessing-operator in C++
> (The grammar of attributes expects tokens in both languages)
>
> Is this divergence intended? It does not seem desirable.
>
> Note that there is implementation divergence amongst C++ compilers here, Clang accepts in all language modes, GCC rejects in all language modes https://godbolt.org/z/Wj5fqdd1x <https://godbolt.org/z/Wj5fqdd1x>

Looks like ## should have the same divergence.

Jens


> https://eel.is/c++draft/lex.operators#1 <https://eel.is/c++draft/lex.operators#1>
> https://eel.is/c++draft/lex.token#nt:token <https://eel.is/c++draft/lex.token#nt:token>
> https://eel.is/c++draft/dcl.attr#nt:balanced-token <https://eel.is/c++draft/dcl.attr#nt:balanced-token>
>
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