https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79885
--- Comment #6 from Jeremy Huddleston Sequoia <jeremyhu at macports dot org> --- Got farther with the Makefile.in edit and setting of CPP and CXXCPP, but failing now because --sysroot=... is not getting passed to xg++ during configure-stage2-gcc: from gcc/config.log: configure:6449: /opt/local/var/macports/build/_Users_jeremy_src_macports_macports-ports_lang_gcc6/libgcc/work/build/./pr ev-gcc/xg++ ... conftest.cpp >&5 conftest.cpp:22:19: fatal error: stdio.h: No such file or directory #include <stdio.h> ^ compilation terminated.