tree.c (build_zero_cst): New.

	* tree.c (build_zero_cst): New.
	* tree.h (build_zero_cst): Declare.
	* tree-ssa-ccp.c (get_constant_value): Accept general operands.
	(get_base_constructor): Break out from ...
	(fold_const_aggregate_ref): Here; handle empty constructors.

	* gcc.dg/torture/pr23821.c: Drop static keyword.
	* gcc.dg/tree-ssa/loop-19.c: Likewise.
	* gcc.dg/tree-ssa/foldconst-4.c: New.

From-SVN: r164250

1 files changed, 12 insertions, 0 deletions

diff --git a/gcc/tree.c b/gcc/tree.c
index c20d3b6..fd593e3 100644
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -1583,6 +1583,18 @@ build_one_cst (tree type)
     }
 }
 
+/* Build 0 constant of type TYPE.  This is used by constructor folding and thus
+   the constant should correspond zero in memory representation.  */
+
+tree
+build_zero_cst (tree type)
+{
+  if (!AGGREGATE_TYPE_P (type))
+    return fold_convert (type, integer_zero_node);
+  return build_constructor (type, NULL);
+}
+
+
 /* Build a BINFO with LEN language slots.  */
 
 tree