https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67498
--- Comment #3 from Vittorio Zecca <zeccav at gmail dot com> --- Still in gfortran 5.3.0 /home/vitti/gcc-5.3.0/gcc/fortran/interface.c:2707:33: runtime error: load of value 1818451807, which is not a valid value for type 'expr_t' interface.c:2707 "&& f->sym->ts.u.cl->length->expr_type == EXPR_CONSTANT" You may reproduce this one with a version of gfortran compiled with -fsanitize=undefined