https://gcc.gnu.org/bugzilla/show_bug.cgi?id=86376
--- Comment #2 from David Binderman <dcb314 at hotmail dot com> --- (In reply to Martin Liška from comment #1) > I'll take a look. Thanks. This configure line seems to work ok: ../trunk/configure --prefix=/home/dcb/gcc/results.262304.ubsan \ --with-build-config=bootstrap-ubsan \ --disable-multilib \ --disable-werror \ --enable-checking=release \ --enable-languages=c,c++ So the problem seems to be either in the fortran area (possible, but unlikely) or the checking flags. I'll have a deeper look.