https://gcc.gnu.org/bugzilla/show_bug.cgi?id=68061
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |jakub at gcc dot gnu.org
--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
This is because with -fconcepts-ts the requires-clause argument is parsed as
logical-or-expression rather than constraint-logical-or-expression and for the
former the [ could be part of postfix-expression in there. Bet that is the
reason why constraint-logical-or-expression exists and allows only
primary-expressions mixed with ||s and &&s.
Perhaps the FE could have a hack, set some parser flag when parsing
requires-clause and in postfix-expression parsing if that flag is set instead
of the [[ error in there pretend [ is not there and ends the expression.
As a workaround,
template <class T>
requires true
void f [[deprecated]] (T);
works.
