Fix PR c++/70096 (wrong code for pointer-to-member-function copy)

gcc/cp/ChangeLog:

	PR c++/70096
	* pt.c (tsubst_decl): Clear the DECL_MODE of the new decl.

gcc/testsuite/ChangeLog:

	PR c++/70096
	* g++.dg/template/ptrmem30.C: New test.

From-SVN: r234391

gcc/cp/ChangeLog

 2016-03-22  Patrick Palka  <ppalka@gcc.gnu.org>
 
+	PR c++/70096
+	* pt.c (tsubst_decl): Clear the DECL_MODE of the new decl.
+
+2016-03-22  Patrick Palka  <ppalka@gcc.gnu.org>
+
 	PR c++/70204
 	* constexpr.c (non_const_var_error): Check
 	DECL_INITIALIZED_BY_CONSTANT_EXPRESSION_P.

gcc/cp/pt.c

@@ -12374,6 +12374,8 @@ tsubst_decl (tree t, tree args, tsubst_flags_t complain)
 	/* The initializer must not be expanded until it is required;
 	   see [temp.inst].  */
 	DECL_INITIAL (r) = NULL_TREE;
+	if (VAR_P (r))
+	  DECL_MODE (r) = VOIDmode;
 	if (CODE_CONTAINS_STRUCT (TREE_CODE (t), TS_DECL_WRTL))
 	  SET_DECL_RTL (r, NULL);
 	DECL_SIZE (r) = DECL_SIZE_UNIT (r) = 0;

gcc/testsuite/ChangeLog

 2016-03-22  Patrick Palka  <ppalka@gcc.gnu.org>
 
+	PR c++/70096
+	* g++.dg/template/ptrmem30.C: New test.
+
+2016-03-22  Patrick Palka  <ppalka@gcc.gnu.org>
+
 	PR c++/70204
 	* g++.dg/cpp0x/constexpr-70204a.C: New test.
 	* g++.dg/cpp0x/constexpr-70204b.C: New test.

gcc/testsuite/g++.dg/template/ptrmem30.C

+// PR c++/70096
+// { dg-do run }
+
+int read;
+
+struct Holder
+{
+  void foo () { read = data; }
+  int data;
+};
+
+void
+poison_stack ()
+{
+  volatile char a[256];
+  __builtin_memset ((void *)a, 0xa, sizeof a);
+}
+
+template <typename F>
+void test1 ()
+{
+  Holder h;
+  h.data = 42;
+  F Holder::*fptr = &Holder::foo;
+  (h.*fptr)();
+}
+
+template <typename F>
+void test2 ()
+{
+  Holder h;
+  h.data = 42;
+  F Holder::*fptr1 = &Holder::foo;
+  F Holder::*fptr2 = fptr1;
+  (h.*fptr2)();
+}
+
+
+int main ()
+{
+  poison_stack ();
+  test1<void()>();
+  poison_stack ();
+  test2<void()>();
+}