[PATCH v3] bb-reorder: Improve compgotos pass (PR71785)

[Segher Boessenkool]

On Fri, Nov 18, 2016 at 03:07:27AM -0600, Segher Boessenkool wrote:
> rtl_merge_blocks does not check rtl_can_merge_blocks_p (and you get a
> quite spectacular ICE when you get it wrong: everything between the two
> blocks is deleted :-) ).  I'll make a separate patch that checks it
> (layout mode already does).

This fails in cfgcleanup.c (in merge_blocks_move_successor_nojumps),
on the "a->next_bb == b" test.  Oh well.


Segher