re PR c++/70615 (ICE on valid code at -O1 and above on x86_64-linux-gnu in add_expr, at tree.c:7870)

PR c++/70615
	* cp-gimplify.c (cp_genericize_r): Expand PTRMEM_CST here.
	(cp_gimplify_expr): Not here.

From-SVN: r234940

gcc/cp/ChangeLog

@@ -1,3 +1,9 @@
+2016-04-13  Jason Merrill  <jason@redhat.com>
+
+	PR c++/70615
+	* cp-gimplify.c (cp_genericize_r): Expand PTRMEM_CST here.
+	(cp_gimplify_expr): Not here.
+
 2016-04-12  Patrick Palka  <ppalka@gcc.gnu.org>
 
 	PR c++/70610

gcc/cp/cp-gimplify.c

@@ -576,11 +576,6 @@ cp_gimplify_expr (tree *expr_p, gimple_seq *pre_p, gimple_seq *post_p)
 
   switch (code)
     {
-    case PTRMEM_CST:
-      *expr_p = cplus_expand_constant (*expr_p);
-      ret = GS_OK;
-      break;
-
     case AGGR_INIT_EXPR:
       simplify_aggr_init_expr (expr_p);
       ret = GS_OK;
@@ -1388,6 +1383,13 @@ cp_genericize_r (tree *stmt_p, int *walk_subtrees, void *data)
 	   || TREE_CODE (stmt) == OMP_SIMD
 	   || TREE_CODE (stmt) == OMP_DISTRIBUTE)
     genericize_omp_for_stmt (stmt_p, walk_subtrees, data);
+  else if (TREE_CODE (stmt) == PTRMEM_CST)
+    {
+      /* By the time we get here we're handing off to the back end, so we don't
+	 need or want to preserve PTRMEM_CST anymore.  */
+      *stmt_p = cplus_expand_constant (stmt);
+      *walk_subtrees = 0;
+    }
   else if ((flag_sanitize
 	    & (SANITIZE_NULL | SANITIZE_ALIGNMENT | SANITIZE_VPTR))
 	   && !wtd->no_sanitize_p)

gcc/testsuite/g++.dg/opt/ptrmem7.C

@@ -0,0 +1,31 @@
+// PR c++/70615
+// { dg-options -O }
+
+struct C
+{
+  virtual void f () {}
+};
+
+struct B
+{
+  virtual ~B () {}
+};
+
+class D : public B, public C
+{
+public:
+  D () {}
+};
+
+typedef void (C::*FP) ();
+typedef void (D::*D_f) ();
+
+int
+main ()
+{
+  D *d = new D ();
+  C *c = d;
+  const FP fptr = (FP) & D::f;
+  (d->*(D_f) fptr) ();
+  return 0;
+}