https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106143
Bug ID: 106143
Summary: Add fix-it for missing ::value on trait with
std::integral_constant base
Product: gcc
Version: unknown
Status: UNCONFIRMED
Keywords: diagnostic
Severity: normal
Priority: P3
Component: c++
Assignee: unassigned at gcc dot gnu.org
Reporter: redi at gcc dot gnu.org
Target Milestone: ---
#include <type_traits>
static_assert( std::is_void<void>, "void is void is void" );
constexpr bool b = std::is_void<void>;
v.C:2:34: error: expected primary-expression before ',' token
2 | static_assert( std::is_void<void>, "void is void is void" );
| ^
v.C:3:38: error: expected primary-expression before ';' token
3 | constexpr bool b = std::is_void<void>;
| ^
I do this all the time: forget to take the ::value of the trait and just use
the type itself. The diagnostic could be improved for this case, by detecting
that the type has a base that is a specialization of std::integral_constant and
suggesting adding ::value as a fix-it:
v.C:2:34: error: expected primary-expression before ',' token
2 | static_assert( std::is_void<void>, "void is void is void" );
| ^
| ::value
v.C:3:38: error: expected primary-expression before ';' token
3 | constexpr bool b = std::is_void<void>;
| ^
| ::value
