[Bug lto/42088] flag_gtoggle in free_lang_data hides -fcompare-debug errors

["rguenth at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #1 from rguenth at gcc dot gnu dot org  2009-11-18 10:28 -------
Hmpf, no testcases ...

./xgcc -B. -c tree.i -O -g -fcompare-debug=-g0

has a compare-debug failure (-O0 does not).  Fixed by

Index: gcc/tree.c
===================================================================
--- gcc/tree.c  (revision 154283)
+++ gcc/tree.c  (working copy)
@@ -4313,7 +4313,8 @@ free_lang_data_in_block (tree fn, tree b
   tp = &BLOCK_VARS (block);
   while (*tp)
     {
-      if (!pointer_set_contains (locals, *tp))
+      if (TREE_CODE (*tp) == VAR_DECL
+         && !pointer_set_contains (locals, *tp))
        *tp = TREE_CHAIN (*tp);
       else
        tp = &TREE_CHAIN (*tp);

Note that UID differences that do not change UID order are a red herring
IMHO and should be tracked down and fixed.  Any idea where this particular
one comes from?  Most of the time it's walking hashtables in hash order,
like FOR_EACH_REFERENCED_VAR does.  Relevant such walkings might be
in insert_phi_nodes, analyze_all_variable_accesses (both easy to fix,
but fixing them doesn't fix the debug miscompare).


-- 

rguenth at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |rguenth at gcc dot gnu dot
                   |dot org                     |org
             Status|UNCONFIRMED                 |ASSIGNED
     Ever Confirmed|0                           |1
   Last reconfirmed|0000-00-00 00:00:00         |2009-11-18 10:28:24
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=42088