https://gcc.gnu.org/bugzilla/show_bug.cgi?id=98061
Bug ID: 98061
Summary: CV qualifiers are incorrectly stripped from the type
of void prvalues
Product: gcc
Version: unknown
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: jason.e.cobb at gmail dot com
Target Milestone: ---
When creating a prvalue of a cv void type, cv qualifiers are incorrectly
stripped.
Consider:
BEGIN EXAMPLE
#include <type_traits>
template<typename T>
using id_t = T;
static_assert(std::is_same_v<decltype(id_t<void const>()), void>);
END EXAMPLE
On Compiler Explorer: https://godbolt.org/z/z3PebY
GCC, Clang, and MSVC accept. ICC rejects, believing the type to instead be
const void (https://godbolt.org/z/Tqvjoo). The results are similar for
volatile.
ICC is correct. The correct type is const void per [expr.type.conv]/2:
> Otherwise, if the type is cv void and the initializer is () or {} (after pack
> expansion, if any), the expression is a prvalue of the specified type that
> performs no initialization.
