https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98768
Bug ID: 98768
Summary: Improve diagnostics for incorrect result type checking
"-> Type" in concepts
Product: gcc
Version: 11.0
Status: UNCONFIRMED
Keywords: diagnostic
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: antoshkka at gmail dot com
Target Milestone: ---
Consider the example:
template <typename Function, typename T>
concept Callable0Arg = requires(Function func) {
func() -> T;
};
The expression "-> T" is valid only if the "func()" returns pointer to a type
that has member "T". At the same time there is an unused "typename T" in the
concept definition.
For such cases a warning like "Unused `T` in concept definition. Did you mean
`-> std::same_as<T>`" would be really helpful.
