https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106850
--- Comment #3 from Alejandro Colomar <colomar.6.4.3 at gmail dot com> --- Ahhh, yeah, something like rvalues don't have qualifiers. I seem to remember now. Maybe the standard should fix this for restrict, because things like clang's _Nonnull would benefit from being kept in such cases. Of course, that might complicate the compiler...
