PR target/88638 - FAIL: fsf-nsstring-format-1.s on darwin
gcc/c-family/ChangeLog:
PR target/88638
* c-attribs.c (positional_argument): Call valid_format_string_type_p
and issue errors if it fails.
* c-common.h (valid_format_string_type_p): Declare.
* c-format.c (valid_stringptr_type_p): Rename...
(valid_format_string_type_p): ...to this and make extern.
(handle_format_arg_attribute): Adjust to new name.
(check_format_string): Same.