gimple-parser.c (c_parser_gimple_postfix_expression): Handle _Literal (char *)…

gimple-parser.c (c_parser_gimple_postfix_expression): Handle _Literal (char *) &"foo" for address literals pointing to STRING_CSTs.

2019-07-01  Richard Biener  <rguenther@suse.de>

	c/
	* gimple-parser.c (c_parser_gimple_postfix_expression): Handle
	_Literal (char *) &"foo" for address literals pointing to
	STRING_CSTs.

	* gcc.dg/gimplefe-42.c: New testcase.

From-SVN: r272872

gcc/c/ChangeLog

+2019-07-01  Richard Biener  <rguenther@suse.de>
+
+	* gimple-parser.c (c_parser_gimple_postfix_expression): Handle
+	_Literal (char *) &"foo" for address literals pointing to
+	STRING_CSTs.
+
 2019-06-24  Martin Sebor  <msebor@redhat.com>
 
 	* c-typeck.c (build_binary_op): Hyphenate floating-point.

gcc/c/gimple-parser.c

@@ -1596,17 +1596,22 @@ c_parser_gimple_postfix_expression (gimple_parser &parser)
 		}
 	      else
 		{
-		  bool neg_p;
+		  bool neg_p, addr_p;
 		  if ((neg_p = c_parser_next_token_is (parser, CPP_MINUS)))
 		    c_parser_consume_token (parser);
+		  if ((addr_p = c_parser_next_token_is (parser, CPP_AND)))
+		    c_parser_consume_token (parser);
 		  tree val = c_parser_gimple_postfix_expression (parser).value;
 		  if (! val
 		      || val == error_mark_node
-		      || ! CONSTANT_CLASS_P (val))
+		      || ! CONSTANT_CLASS_P (val)
+		      || (addr_p && TREE_CODE (val) != STRING_CST))
 		    {
 		      c_parser_error (parser, "invalid _Literal");
 		      return expr;
 		    }
+		  if (addr_p)
+		    val = build1 (ADDR_EXPR, type, val);
 		  if (neg_p)
 		    {
 		      val = const_unop (NEGATE_EXPR, TREE_TYPE (val), val);

gcc/testsuite/ChangeLog

+2019-07-01  Richard Biener  <rguenther@suse.de>
+
+	* gcc.dg/gimplefe-42.c: New testcase.
+
 2019-07-01  Hristian Kirtchev  <kirtchev@adacore.com>
 
 	* gnat.dg/sets1.adb: Update.

gcc/testsuite/gcc.dg/gimplefe-42.c

+/* { dg-do compile } */
+/* { dg-options "-fgimple" } */
+
+typedef char ref_all_char __attribute__((may_alias));
+char a[7];
+__GIMPLE void f()
+{
+  int _1;
+  /* string literals inside __MEM need their address taken.  */
+  __MEM <char[7]> ((ref_all_char *)&a)
+    = __MEM <char[7]> (_Literal (char *) &"654321");
+  /* but plain assignment also works.  */
+  __MEM <char[7]> ((ref_all_char *)&a) = "654321";
+  /* also punning with int.  */
+  _1 = __MEM <int> (_Literal (char *) &"654321");
+  __MEM <int> ((ref_all_char *)&a) = _1;
+  return;
+}