https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102675
--- Comment #3 from H.J. Lu <hjl.tools at gmail dot com> --- (In reply to Gerald Pfeifer from comment #2) > (In reply to H.J. Lu from comment #1) > > That file is FreeBSD specific. Can you use a local patch to force > > /usr/include/md5.h, like > > > > #include_next <md5.h> > > I tried replacing #include <md5.h> by #include_next <md5.h>; that did > not lead to any change. > > Using #include "/usr/include/md5.h" restored bootstrap. > > This confirms my hypothesis that it's GCC's md5.h being picked up that > is the issue for this regression. Does this file use any GCC specific header files? If not, you can filter out GCC specific -Ixxx from CXX and CXXFLAGS for this file. Or can you prepend -Isystem-headr-directory to CXXFLAGS for this file?