https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67961
--- Comment #2 from Jonathan Wakely <redi at gcc dot gnu.org> --- (In reply to other+gcc from comment #0) > where type of that rvalue variable is uint32_t not std::size_t. There is no rvalue of type uint32_t. The type of the **lvalue** is uint32_t. The rvalue is the temporary that gets created implicitly, which is of type size_t. FWIW clang doesn't mention rvalues, it just says there is no matching function for the call because ... prog.cc:4:6: note: candidate function not viable: no known conversion from 'std::uint32_t' (aka 'unsigned int') to 'std::size_t &' (aka 'unsigned long &') for 1st argument
