gcc12 just reached 3000 days of uptime, which amounts to a little more than 8 years!
Here is a bit of history on this machine hosted by FSF France:
2007-06-24 gcc11/12/13 installed 2007-07-22 gcc11/12/13 moved to datacenter, gcc01..09 stopped, gcc08 online at a temporary location 2007-11-25 gcc11/12/13 moved to new datacenter, downtime 1700 UTC to 2000 UTC 2008-05-18 gcc11 and gcc12 moved to new datacenter (same IP). 2009-08-14 planned downtime for gcc11/gcc12 at the end of august 2009-08-31 gcc12 is down, please use gcc13 until gcc12 is restored 2009-09-21 gcc11/12 are up in their new FSF France datacenter in Rennes
Since then, the machine (and its hosting facility) has been extremely stable. Of course, since it is still running Debian 5 "lenny" and has limited hardware resources for today's standards, its usage is quite low nowadays.
There were even older machines in the GCC compile farm, see the history of the project.