https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67496
--- Comment #7 from Vittorio Zecca <zeccav at gmail dot com> --- I understand that you are still seeing a message like this ../../gcc-6.1.0/gcc/fortran/trans-array.c:2233:27: runtime error: load of value 176, which is not a valid value for type 'bool' right? If yes, the problem might well be in ubsan, unless it has been fixed in 7.0.0. I'll look into this.