Question about an inconsistency - 1

Hi,

I have a question regarding the source code in file pg_proc.h (postgresql-9.4.4).

At line 1224 (copied below) why the 28th identifier is timestamp_eq?

DATA(insert OID = 1152 ( timestamptz_eq PGNSP PGUID 12 1 0 0 0 f f f t t f i 2 0 16 "1184 1184" _null_ _null_ _null_ _null_ timestamp_eq _null_ _null_ _null_ ));

I would expect it to be timestamptz_eq (the same as the 5th identifier from the same line). Shouldn't it be the same
like in the line 2940 copied also below having the same identifier in the 28th and 5th positions (timestamp_eq)?

DATA(insert OID = 2052 ( timestamp_eq PGNSP PGUID 12 1 0 0 0 f f f t t f i 2 0 16 "1114 1114" _null_ _null_ _null_ _null_ timestamp_eq _null_ _null_ _null_ ));

A similar question can be asked for lines 1225 to 1229 (but for their specific identifiers).

Regards,
Pepi