https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66066
--- Comment #1 from Marek Polacek <mpolacek at gcc dot gnu.org> --- Yes, that is expected (in C99!). See <https://gcc.gnu.org/ml/gcc-patches/2015-04/msg01946.html>. New tests c90-left-shift-1.c and c99-left-shift-1.c explicitly test such behavior.
