On Mon, Jan 5, 2026 at 2:04 AM Bingzhi via Gcc-bugs <[email protected]> wrote: > > In GCC 15.2.0, the following code compiles: > template<typename T> concept Can_sizeof = sizeof(T);
See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102012 . > > > I don't know which rule in the ISO C++20, but this code doesn't compile under > Clang 21.1.5: error: atomic constraint must be > of type 'bool' (found 'unsigned long').
