https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89585
--- Comment #5 from Harald van Dijk <harald at gigawatt dot nl> --- According to <https://gcc.gnu.org/ml/gcc-patches/2018-12/msg01698.html>, the GCC 8 backport was not supposed to break existing code, it was supposed to warn about code that would become invalid in GCC 9. It seems like this case was missed.
