re PR c++/65525 (ICE: sorry, unimplemented: unexpected AST of kind mem_ref…

re PR c++/65525 (ICE: sorry, unimplemented: unexpected AST of kind mem_ref (-std=c++14, ICE: in potential_constant_expression_1, at cp/constexpr.c:4432))

	PR c++/65525
	* constexpr.c (potential_constant_expression_1): Handle MEM_REF.

From-SVN: r221699

gcc/cp/ChangeLog

+2015-03-26  Jason Merrill  <jason@redhat.com>
+
+	PR c++/65525
+	* constexpr.c (potential_constant_expression_1): Handle MEM_REF.
+
 2015-03-25  Marek Polacek  <polacek@redhat.com>
 
 	PR c++/65558

gcc/cp/constexpr.c

@@ -4395,6 +4395,7 @@ potential_constant_expression_1 (tree t, bool want_rval, bool strict,
     case ARRAY_RANGE_REF:
     case MEMBER_REF:
     case DOTSTAR_EXPR:
+    case MEM_REF:
     binary:
       for (i = 0; i < 2; ++i)
 	if (!RECUR (TREE_OPERAND (t, i), want_rval))

gcc/testsuite/g++.dg/parse/assign1.C

+// PR c++/65525
+
+struct A
+{
+    int x;
+    char y; // Actually, short and bool (types smaller than int?) trigger this ICE too
+    // Also: the problem doesn't occur if you put the smaller type first, e.g. "char x; int y;"
+
+    A(int x) {} // custom ctor needed for ICE
+};
+
+int main()
+{
+    A a(0), x(1), y(2);
+
+    x = a; // OK
+    y = a; // OK
+    x = y = a; // ICE: sorry, unimplemented: unexpected AST of kind mem_ref
+    // internal compiler error: in potential_constant_expression_1, at cp/constexpr.c:4432
+
+    return 0;
+}