[Bug c++/95287] [DR2233] Incorrect default argument checking for specializations of functions with parameter packs

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=95287

Jonathan Wakely <redi at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|Incorrect default argument  |[DR2233] Incorrect default
                   |checking for                |argument checking for
                   |specializations of          |specializations of
                   |functions with parameter    |functions with parameter
                   |packs                       |packs
           Keywords|                            |rejects-valid
             Blocks|                            |94404
     Ever confirmed|0                           |1
   Last reconfirmed|                            |2025-03-11
             Status|UNCONFIRMED                 |NEW
                 CC|                            |jason at gcc dot gnu.org

--- Comment #3 from Jonathan Wakely <redi at gcc dot gnu.org> ---
https://cplusplus.github.io/CWG/issues/2233.html was accepted as a DR in 2018

Jason committed r7-4490-g559f2bbc362f31 in 2016:

    CWG 2233 - default arg and parameter pack

            * typeck.c (convert_arguments): Handle default arg followed by
none.


GCC correctly handles both examples in the issue resolution, the ill-formed one
in [expr.call] and the well-formed on in [dcl.fct.default]. The issue doesn't
actually talk about explicit specializations of function templates, as used in
the testcase here.


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94404
[Bug 94404] [meta-bug] C++ core issues