[Bug c++/86728] [8/9 Regression] unexpected error: conversion from '<lambda(<type error>, ...)>' to non-scalar type 'std::function<void(int)>' requested

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86728

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |NEW
   Last reconfirmed|                            |2018-07-30
                 CC|                            |jason at redhat dot com
   Target Milestone|8.3                         |7.4
     Ever confirmed|0                           |1
      Known to fail|8.1.0                       |7.3.1, 8.2.0, 9.0

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
The full error is:

86728.cc:5:43: error: parameter packs not expanded with ‘...’:
86728.cc:5:43: note:         ‘auto:2’
86728.cc:5:47: error: conversion from ‘<lambda(<type error>, ...)>’ to
non-scalar type ‘std::function<void(int)>’ requested


It started to fail with r259015:

           PR c++/64095 - auto... parameter pack.

            * parser.c (cp_parser_parameter_declaration): Handle turning autos
            into packs here.
            (cp_parser_parameter_declaration_list): Not here.