https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92500
--- Comment #3 from anlauf at gcc dot gnu.org --- Looking at related testcases, does replacing #include "ISO_Fortran_binding.h" by #include "../../../libgfortran/ISO_Fortran_binding.h" help?
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=92500
--- Comment #3 from anlauf at gcc dot gnu.org --- Looking at related testcases, does replacing #include "ISO_Fortran_binding.h" by #include "../../../libgfortran/ISO_Fortran_binding.h" help?