https://gcc.gnu.org/bugzilla/show_bug.cgi?id=105104
--- Comment #1 from John Eivind Helset <jehelset at gmail dot com> --- Indices of `bb` and `case_bb` in `convert_single_case_switch` are: (gdb) p bb->index $18 = 154 (gdb) p case_bb->index $19 = 157 If that helps.