https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85069
Bug ID: 85069
Summary: std::invoke_result returns a wrong type
Product: gcc
Version: 8.0.1
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: akrzemi1 at gmail dot com
Target Milestone: ---
`std::invoke_result` returns a wrong type. Consider the following source file:
```
#include <type_traits>
// log_type displays the type of T in compiler error
template <typename T> void log_type() = delete;
struct F
{
int operator()() { return 9; }
};
int main()
{
log_type<std::invoke_result_t<F()>>();
}
```
I do not expect it to compile, but when generating error message it displays
the "return type" from the type trait. I expect the type of
`std::invoke_result_t<F()>` to be `int`, but instead, the compiler reports that
it is `F`. I do not get this problem when I use the deprecated trait
`std::result_of` instead.
