analyzer: support null operands in remove_ssa_names

gcc/analyzer/ChangeLog:
	* access-diagram.cc (remove_ssa_names): Support operands being
	NULL_TREE, such as e.g. for COMPONENT_REF's operand 2.

Signed-off-by: David Malcolm <dmalcolm@redhat.com>

diff --git a/gcc/analyzer/access-diagram.cc b/gcc/analyzer/access-diagram.cc
index 2836308c01999c863c99d41c1301566f6a797288..a9c5c89995030b57a0d10736090d5f3d549c0c5b 100644 (file)
--- a/gcc/analyzer/access-diagram.cc
+++ b/gcc/analyzer/access-diagram.cc
@@ -311,7 +311,8 @@ remove_ssa_names (tree expr)
     return SSA_NAME_VAR (expr);
   tree t = copy_node (expr);
   for (int i = 0; i < TREE_OPERAND_LENGTH (expr); i++)
-    TREE_OPERAND (t, i) = remove_ssa_names (TREE_OPERAND (expr, i));
+    if (TREE_OPERAND (expr, i))
+      TREE_OPERAND (t, i) = remove_ssa_names (TREE_OPERAND (expr, i));
   return t;
 }