diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index 1200433e317..21b55857260 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,8 @@
+2005-11-19  Joseph S. Myers  <joseph@codesourcery.com>
+
+	* combine.c (make_compound_operation): Swap operands of
+	commutative operation if necessary before returning.
+
 2005-11-19  Richard Guenther  <rguenther@suse.de>
 
 	PR middle-end/23294
diff --git a/gcc/combine.c b/gcc/combine.c
index 9f910a7b336..b43b9b621c6 100644
--- a/gcc/combine.c
+++ b/gcc/combine.c
@@ -6914,6 +6914,16 @@ make_compound_operation (rtx x, enum rtx_code in_code)
 	SUBST (XEXP (x, i), new);
       }
 
+  /* If this is a commutative operation, the changes to the operands
+     may have made it noncanonical.  */
+  if (COMMUTATIVE_ARITH_P (x)
+      && swap_commutative_operands_p (XEXP (x, 0), XEXP (x, 1)))
+    {
+      tem = XEXP (x, 0);
+      SUBST (XEXP (x, 0), XEXP (x, 1));
+      SUBST (XEXP (x, 1), tem);
+    }
+
   return x;
 }