[Bug other/49533] [4.7 regression] Revision 174989 (ipa-inline-transform.c) regressions

[markus at trippelsdorf dot de]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49533

--- Comment #8 from Markus Trippelsdorf <markus at trippelsdorf dot de> 
2011-07-13 21:13:31 UTC ---
Hmm, that whole approach doesn't seem to work.

The following patch survives building of stellarium and explains the 
failures that I've reported above:

diff --git a/gcc/ipa-inline-transform.c b/gcc/ipa-inline-transform.c
index c329bea..bef1d38 100644
--- a/gcc/ipa-inline-transform.c
+++ b/gcc/ipa-inline-transform.c
@@ -122,7 +122,10 @@ can_remove_node_now_p (struct cgraph_node *node, struct
cgraph_edge *e)
        next != node; next = next->same_comdat_group)
     if (node->callers && node->callers != e
        && !can_remove_node_now_p_1 (node))
-      return false;
+      {
+        gcc_unreachable();
+        return false;
+      }
   return true;
 }

Even when one changes node to next in the if clause,
"next->callers == e" is always true and the following 
patch also survives building of stellarium. But it merely
brings us back to the status quo before commit 7791b0eb56c3c
went in... 

 diff --git a/gcc/ipa-inline-transform.c b/gcc/ipa-inline-transform.c
index c329bea..2a09de8 100644
--- a/gcc/ipa-inline-transform.c
+++ b/gcc/ipa-inline-transform.c
@@ -120,9 +120,13 @@ can_remove_node_now_p (struct cgraph_node *node, struct
cgraph_edge *e)
     return true;
   for (next = node->same_comdat_group;
        next != node; next = next->same_comdat_group)
-    if (node->callers && node->callers != e
-       && !can_remove_node_now_p_1 (node))
-      return false;
+    if (next->callers
+       && !can_remove_node_now_p_1 (next))
+      {
+        gcc_assert (next->callers == e);
+        return false;
+      }
+  gcc_unreachable();
   return true;
 }