diff --git a/src/libiso8601/calc.c b/src/libiso8601/calc.c
index 9db1d9e..88a1796 100644
--- a/src/libiso8601/calc.c
+++ b/src/libiso8601/calc.c
@@ -340,6 +340,8 @@ int iso8601_from_week(struct iso8601_date* date, int isoyear, int week, int wday
 
     // now simply add in the day offset and days/weeks elapsed
     date->day += day1off + (week - 1) * 7 + wday - 1;
+
+    return 0;
 }
 
 
diff --git a/src/libiso8601/functions.h b/src/libiso8601/functions.h
index 8e7c57d..c13bf29 100644
--- a/src/libiso8601/functions.h
+++ b/src/libiso8601/functions.h
@@ -21,7 +21,9 @@ int iso8601_isleap(int year);
 void iso8601_to_cal(int* year, int* month, int* day, const struct iso8601_date* date);
 int iso8601_from_cal(struct iso8601_date* date, int year, int month, int day);
 void iso8601_to_ord(int* year, int* oday, const struct iso8601_date* date);
+int iso8601_from_ord(struct iso8601_date* date, int year, int oday);
 void iso8601_to_week(int* year, int* week, int* wday, const struct iso8601_date* date);
+int iso8601_from_week(struct iso8601_date* date, int year, int week, int wday);
 
 /* print.c */
 void iso8601_print(char* str, int amt, const struct iso8601_date* date,