diff --git a/cmaybe.h b/cmaybe.h
index da43453..b3b2673 100644
--- a/cmaybe.h
+++ b/cmaybe.h
@@ -1,18 +1,18 @@
 #ifndef CMAYBE_H
 #define CMAYBE_H
 
-#define MAYBE_TYPE(name, type) struct maybe_##name {type value; char is_value;}
-#define MAYBE(name) struct maybe_##name
+#define MAYBE_TYPE(name, type) struct cmaybe_maybe_##name {type value; char is_value;}
+#define MAYBE(name) struct cmaybe_maybe_##name
 
-#define ENABLE_RETURN(name) MAYBE(name) _return_value
+#define ENABLE_RETURN(name) MAYBE(name) cmaybe_return_value
 #define RETURN_VALUE(x) do {\
-	_return_value.is_value = 1;\
-	_return_value.value = x;\
-	return _return_value;\
+	cmaybe_return_value.is_value = 1;\
+	cmaybe_return_value.value = x;\
+	return cmaybe_return_value;\
 } while(0)
 #define RETURN_NOTHING() do {\
-	_return_value.is_value = 0;\
-	return _return_value;\
+	cmaybe_return_value.is_value = 0;\
+	return cmaybe_return_value;\
 } while(0)
 
 #define IS_VALUE(x) if ((x).is_value)