[Bug c/88237] __extension__ in function declaration argument list causes error

[jozef.l at mittosystems dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88237

--- Comment #1 from Jozef Lawrynowicz <jozef.l at mittosystems dot com> ---
For C++ the errors are:

> g++ -S tester.c
> 
> tester.c:11:10: error: variable or field 'foo' declared void
>    11 | void foo (__extension__ int a);
>       |          ^
> tester.c:11:25: error: expected primary-expression before 'int'
>    11 | void foo (__extension__ int a);