https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62254
--- Comment #20 from Julien Margetts <jmargetts at ocz dot com> --- It is the gcc_assert (REG_P (operands[0])); in arm_reload_in_hi which fires, which as far as I can see is still in trunk today. At this point rtx operands[0] looks like this: 08 2d c2 7a 53 2b 00 00 The first pass through this code (no assert) looks like this: 80 b8 c1 7a 53 2b 00 00 NOTE: This was recreated by merging both patches from trunk into otherwise unchanged 4.9.3 release sources, as I am trying to back port this fix to 4.9.3