https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106102
--- Comment #2 from Richard Biener <rguenth at gcc dot gnu.org> --- The failure can only happen if system headers are included after gcc posioning. All system headers need to be included from system.h for this reason. I think gcc/cp/mapper-resolver.cc needs to arrange the ../../c++tools/resolver.cc code from not including anything.
