theres no time like no time

[Carl Gustav Johnson]

I finally saw it happen with my own eyes!  Once or twice a month I wake up
to find the date/time across the top of the screen has been replaced with
a pretty dot pattern.  I finally saw this occur.  I was compiling a 
C program I modified slightly, when slowly the time went to dots.
I don't believe cc is to blame.  My questions are:
1) does anyone have any idea what why how this happened?
2) is there an easy way to get the date/time back without rebooting
   ( the systems clock is ok because update times on files work)

Thanks in advance,
Carl Johnson (stil no slick quote)