Add casts to CMPERROR macro to silence SunPro compiler warnings about
integer overflow in << operator.
diff --git a/Objects/listobject.c b/Objects/listobject.c
index 2fb67b9..8aca28d 100644
--- a/Objects/listobject.c
+++ b/Objects/listobject.c
@@ -560,7 +560,7 @@
/* CMPERROR is returned by our comparison function when an error
occurred. This is the largest negative integer (0x80000000 on a
32-bit system). */
-#define CMPERROR (1 << (8*sizeof(int) - 1))
+#define CMPERROR ( (int) ((unsigned int)1 << (8*sizeof(int) - 1)) )
/* Comparison function. Takes care of calling a user-supplied
comparison function (any callable Python object). Calls the