[Bug regression/56131] [4.8 regression] gcc.dg/pr56035.c ICEs gcc on sparc-linux

[vries at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=56131

--- Comment #3 from vries at gcc dot gnu.org 2013-01-29 00:28:38 UTC ---
Using NOTE_BASIC_BLOCK instead of BLOCK_FOR_INSN on bb_note allows us to get
the bb.

This tentative patch:
...
Index: cfgrtl.c
===================================================================
--- cfgrtl.c (revision 195240)
+++ cfgrtl.c (working copy)
@@ -144,9 +144,11 @@ delete_insn (rtx insn)
       NOTE_DELETED_LABEL_NAME (insn) = name;

       if (bb_note != NULL_RTX && NOTE_INSN_BASIC_BLOCK_P (bb_note)
-          && BLOCK_FOR_INSN (bb_note) == bb)
+          && (bb == NULL
+          || NOTE_BASIC_BLOCK (bb_note) == bb))
         {
           reorder_insns_nobb (insn, insn, bb_note);
+          bb = NOTE_BASIC_BLOCK (bb_note);
           BB_HEAD (bb) = bb_note;
           if (BB_END (bb) == bb_note)
         BB_END (bb) = insn;
...

gives the following result:
...
(note 23 221 22 [bb 3] NOTE_INSN_BASIC_BLOCK)
(note 22 23 67 ("lbl1") NOTE_INSN_DELETED_LABEL 3)
...