https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83892
--- Comment #6 from simon at pushface dot org --- I tried check-gnat, which also shows additional lto-related failures. Running with lto shows 5 additional FAILs (and 3 fewer PASSes???) LTO: Running target unix/-flto/-g0 ... === gnat Summary === # of expected passes 2673 # of unexpected failures 16 # of expected failures 24 # of unsupported tests 7 /Volumes/Miscellaneous/tmp/gcc-256927-build/gcc/gnatmake version 8.0.1 20180121 (experimental) No LTO: Running target unix/-g ... === gnat Summary === # of expected passes 2676 # of unexpected failures 11 # of expected failures 24 # of unsupported tests 7 /Volumes/Miscellaneous/tmp/gcc-256927-build/gcc/gnatmake version 8.0.1 20180121 (experimental)