diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 86c7dc61237..92f660241d4 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,5 +1,10 @@
 2011-12-21  Jakub Jelinek  <jakub@redhat.com>
 
+	* tree-vect-patterns.c (vect_operation_fits_smaller_type): Initialize
+	*op0 and *op1 to NULL_TREE first to avoid warnings.
+	* calls.c (initialize_argument_information): Initialize base to avoid
+	warnings.
+
 	PR middle-end/51644
 	PR middle-end/51647
 	* tree-eh.c (decide_copy_try_finally): At -O0, return true
diff --git a/gcc/calls.c b/gcc/calls.c
index 0ef0cad8d27..c8d0b849985 100644
--- a/gcc/calls.c
+++ b/gcc/calls.c
@@ -1157,7 +1157,7 @@ initialize_argument_information (int num_actuals ATTRIBUTE_UNUSED,
 			     type, argpos < n_named_args))
 	{
 	  bool callee_copies;
-	  tree base;
+	  tree base = NULL_TREE;
 
 	  callee_copies
 	    = reference_callee_copied (args_so_far_pnt, TYPE_MODE (type),
diff --git a/gcc/tree-vect-patterns.c b/gcc/tree-vect-patterns.c
index a5b8af911aa..46d43ce44ad 100644
--- a/gcc/tree-vect-patterns.c
+++ b/gcc/tree-vect-patterns.c
@@ -900,6 +900,8 @@ vect_operation_fits_smaller_type (gimple stmt, tree def, tree *new_type,
   loop_vec_info loop_info = STMT_VINFO_LOOP_VINFO (vinfo_for_stmt (stmt));
   struct loop *loop = LOOP_VINFO_LOOP (loop_info);
 
+  *op0 = NULL_TREE;
+  *op1 = NULL_TREE;
   *new_def_stmt = NULL;
 
   if (!is_gimple_assign (stmt))