why parse.c update

[Larry Evans]

I'm currently doing cvs update and  the  tail of messages from the cvs
server are:

P gcc/cp/optimize.c
RCS file: /cvs/gcc/egcs/gcc/cp/parse.c,v
retrieving revision 1.165
retrieving revision 1.168
Merging differences between 1.165 and 1.168 into parse.c

However, I don't understand why parse.c needs updating since it's
created from parse.y.
This wouldn't be such a problem but the update it taking a very long
time.  Also, the
kppp statistics show very little traffic.

Could someone please suggest someway to speed this up?

TIA.