https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83391
--- Comment #6 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
The bb is split in:
#0 gsi_split_seq_before (i=0x7fffffffd940, pnew_seq=0x7fffffffd918) at
../../gcc/gimple-iterator.c:415
#1 0x00000000011fc89d in gimple_split_block (bb=<basic_block 0x7fffefacb888
(9)>, stmt=0x0) at ../../gcc/tree-cfg.c:6130
#2 0x0000000000bf2f15 in split_block_1 (bb=<basic_block 0x7fffefacb888 (9)>,
i=0x0) at ../../gcc/cfghooks.c:520
#3 0x0000000000bf30d4 in split_block_after_labels (bb=<basic_block
0x7fffefacb888 (9)>) at ../../gcc/cfghooks.c:572
#4 0x0000000000bf3aa7 in make_forwarder_block (bb=<basic_block 0x7fffefacb888
(9)>, redirect_edge_p=0xc0438c <mfb_keep_just(edge_def*)>,
new_bb_cbk=0x0) at ../../gcc/cfghooks.c:875
#5 0x0000000000c0462b in create_preheader (loop=0x7fffefc20330, flags=1) at
../../gcc/cfgloopmanip.c:1501
#6 0x0000000000c04788 in create_preheaders (flags=1) at
../../gcc/cfgloopmanip.c:1552
#7 0x0000000000f6dab6 in apply_loop_flags (flags=3) at
../../gcc/loop-init.c:64
#8 0x0000000000f6dbf4 in loop_optimizer_init (flags=3) at
../../gcc/loop-init.c:123
Do we really need to allow debug stmts before labels?
If yes, I have a fix for gimple_make_forwarder_block.
