On 06/09/2025 15:36, Alejandro Colomar wrote:
While this syntax is not standard, there's a certain degree of consensus within the C Committee that, if this was ever standardized, there's a preference to have a single list of forward declarations of parameters. This would allow eventually adding another semicolon in function prototypes to separate a different feature.
For the benefit of others, the context is that WG14 preferred N3433 ("Chris's version") to N3394 ("Martin's version") by 15 / 3 / 11 (Y/N/A).
See the meeting minutes at https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3583.htm
The latest version of the preferred paper is https://www.open-std.org/jtc1/sc22/wg14/www/docs/n3681.pdf
So, make multiple lists of forward declarations of parameters obsolescent, and produce a new diagnostic, -Wmultiple-parameter-fwd-decl-lists, which diagnoses uses of this obsolescent syntax. Forward declarations of parameters are a rarely used feature, AFAIK, so this shouldn't be problematic in -Wextra. Eventually, we may want to move this into a default diagnostic, and later an error. than one list of forward declarations of parameters
-- Christopher Bazley Staff Software Engineer, GNU Tools Team. Arm Ltd, 110 Fulbourn Road, Cambridge, CB1 9NJ, UK. http://www.arm.com/
