Undefine TRUE and FALSE before redefining them.
diff --git a/Modules/cPickle.c b/Modules/cPickle.c
index 70ead48..2484365 100644
--- a/Modules/cPickle.c
+++ b/Modules/cPickle.c
@@ -76,7 +76,9 @@
 #define TUPLE       't'
 #define EMPTY_TUPLE ')'
 #define SETITEMS    'u'
+#undef TRUE
 #define TRUE        "I01\n"
+#undef FALSE
 #define FALSE       "I00\n"