Le sam. 12 oct. 2019 à 17:44, Romain Geissler <romain.geiss...@gmail.com> a écrit : > > It looks like this creates the following error when I try to bootstrap > clang 9.0.0 using the latest gcc and libstdc++ from trunk. Note that > with g++, there is no problem, however it looks like clang++ has some > problem with the new header. I don't know if this is an issue on > libstdc++ side or clang++ side.
__is_same_as is not implemented as a compiler builtin in clang++ unlike g++, thus the error on clang 9.0.0 side. It looks like current clang trunk doesn't define __is_same_as either. Until clang implements this support (if it ever will), usage of __is_same_as in libstdc++ shall be conditional, only when __has_builtin(__is_same_as) is true (however that would require that gcc implements __has_builtin, as implemented here: https://gcc.gnu.org/ml/gcc-patches/2019-10/msg00062.html ) Cheers, Romain
