[PATCH] Fix PR64280

[PATCH] Fix PR64280

[Richard Biener]

The following fixes PR64280 by properly guarding the assert
with whether we are going to change SSA_NAME_OCCURS_IN_ABNORMAL_PHI.
Recent changes in what we allow to propagate otherwise happily
will trigger it.

Bootstrapped on x86_64-unknown-linux-gnu, testing in progress.

Richard.

2014-12-12  Richard Biener  <rguenther@suse.de>

	PR middle-end/64280
	* tree-cfg.c (replace_uses_by): Guard assert properly.

	* g++.dg/torture/pr64280.C: New testcase.

Index: gcc/tree-cfg.c
===================================================================
--- gcc/tree-cfg.c	(revision 218661)
+++ gcc/tree-cfg.c	(working copy)
@@ -1781,7 +1781,8 @@ replace_uses_by (tree name, tree val)
 	    {
 	      e = gimple_phi_arg_edge (as_a <gphi *> (stmt),
 				       PHI_ARG_INDEX_FROM_USE (use));
-	      if (e->flags & EDGE_ABNORMAL)
+	      if (e->flags & EDGE_ABNORMAL
+		  && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (val))
 		{
 		  /* This can only occur for virtual operands, since
 		     for the real ones SSA_NAME_OCCURS_IN_ABNORMAL_PHI (name))
Index: gcc/testsuite/g++.dg/torture/pr64280.C
===================================================================
--- gcc/testsuite/g++.dg/torture/pr64280.C	(revision 0)
+++ gcc/testsuite/g++.dg/torture/pr64280.C	(working copy)
@@ -0,0 +1,42 @@
+// { dg-do compile }
+
+class A
+{
+public:
+  A ();
+};
+class B
+{
+public:
+  B (int);
+  operator void *() { return m_fn1 () ? 0 : this; }
+  int m_fn1 ();
+};
+typedef int jmp_buf[];
+struct C
+{
+  jmp_buf cond_;
+};
+class F
+{
+  C what_;
+  bool m_fn2 ();
+};
+int _setjmp (int[]);
+void longjmp ();
+class D
+{
+public:
+  D () { longjmp (); }
+};
+bool
+F::m_fn2 ()
+{
+  B a (0);
+  if (a)
+    if (_setjmp (what_.cond_))
+      return 0;
+    else
+      D ();
+  A b;
+}