[Bug c++/85991] [Concepts] Template placeholder: ICE cp_parser_lookup_name, at cp/parser.c:26223

[redi at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85991

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

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Blocks|                            |67491

--- Comment #1 from Jonathan Wakely <redi at gcc dot gnu.org> ---
No ICE with current trunk:

b.cc:1:51: warning: the 'bool' keyword is not allowed in a C++20 concept
definition
    1 | template <template <typename> class, int> concept bool TmplC = true;
      |                                                   ^~~~
b.cc:3:10: error: 'TmplC' does not constrain a type
    3 | void f(A<TmplC<0>> *);
      |          ^~~~~~~
b.cc:1:56: note: concept defined here
    1 | template <template <typename> class, int> concept bool TmplC = true;
      |                                                        ^~~~~
b.cc:3:10: error: wrong number of template arguments (1, should be 2)
    3 | void f(A<TmplC<0>> *);
      |          ^~~~~~~
b.cc:1:56: note: provided for 'template<template<class>
class<template-parameter-1-1>, int <anonymous> > concept const bool TmplC<
<template-parameter-1-1>, <anonymous> >'
    1 | template <template <typename> class, int> concept bool TmplC = true;
      |                                                        ^~~~~
b.cc:3:10: error: wrong number of template arguments (1, should be 2)
    3 | void f(A<TmplC<0>> *);
      |          ^~~~~~~
b.cc:1:56: note: provided for 'template<template<class>
class<template-parameter-1-1>, int <anonymous> > concept const bool TmplC<
<template-parameter-1-1>, <anonymous> >'
    1 | template <template <typename> class, int> concept bool TmplC = true;
      |                                                        ^~~~~
b.cc:3:17: error: template argument 1 is invalid
    3 | void f(A<TmplC<0>> *);
      |                 ^~


Referenced Bugs:

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67491
[Bug 67491] [meta-bug] concepts issues