https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87162
--- Comment #6 from Wen Yang <yellowriver2010 at hotmail dot com> --- We may simply construct this error scenario: # /var/weny/release_gcc_trunk/usr/local/libexec/gcc/x86_64-pc-linux-gnu/9.0.0/cc1 -fdump-passes -fgnu-tm applets.i This section of code has a bug: static bool gate_tm_init (void) { if (!flag_tm) return false; calculate_dominance_info (CDI_DOMINATORS); ---》cfun may be NULL.