https://gcc.gnu.org/bugzilla/show_bug.cgi?id=109049
Bug ID: 109049
Summary: std::declval gives wrong result for cv void
Product: gcc
Version: 12.2.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: libstdc++
Assignee: unassigned at gcc dot gnu.org
Reporter: fsb4000 at yandex dot ru
Target Milestone: ---
A. Jiang <d...@live.cn> found that:
Quote:
"The return type is... cursed for cv void.
It seems that decltype(std::declval<const void>) should be const void() (until
C++17) / const void() noexcept (since C++17) (same for volatile void and const
volatile void), but the cv-qualifiers are dropped"
Code example:
#include <utility>
#include <type_traits>
int main() {
static_assert(std::is_same_v<decltype(std::declval<const void>), const void
() noexcept>);
static_assert(std::is_same_v<decltype(std::declval<volatile void>),
volatile void () noexcept>);
}
https://gcc.godbolt.org/z/TMe3v9sxh
I've created the same issue for libc++:
https://github.com/llvm/llvm-project/issues/61232
