https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88736
Martin Sebor <msebor at gcc dot gnu.org> changed: What |Removed |Added ---------------------------------------------------------------------------- Status|UNCONFIRMED |NEW Last reconfirmed| |2019-01-12 CC| |msebor at gcc dot gnu.org Ever confirmed|0 |1 --- Comment #1 from Martin Sebor <msebor at gcc dot gnu.org> --- I agree. <cstddef> defines C library names in both namespace std and the global namespace but C++ library names only in std. For some reason, GCC's <stddef.h> defines nullptr_t in the global namespace (and libstdc++ <cstddef> in std).