2.2.3 [W3C-XSD] Section 3.2.12, gMonthDay


The specification states:

 Since the lexical representation allows an optional time zone indicator, gMonthDay 
 values are partially ordered because it may not be possible to unequivocally 
 determine the order of two values one of which has a time zone and the other does 
 not. If gMonthDay values are considered as periods of time, in an arbitrary leap 
 year, the order relation on gMonthDay values is the order relation on their 
 starting instants. This is discussed in Order relation on dateTime (§ 
 See also Adding durations to dateTimes (§E). Pairs of gMonthDay values with or 
 without time zone indicators are totally ordered.


Indeterminate comparisons are considered to be determinate.