sac2c causes sporadic freezes of display manager, for 10-30 seconds

Bugzilla Link	991
Created on	Jul 07, 2012 22:04
Version	svn
OS	Linux
Architecture	PC

Extended Description

sac2c -V
sac2c v1.00-beta (Haggis And Apple)
 developer rev 18043:MODIFIED linux-gnu_x86_64
 (Sat Jul  7 15:57:25 EDT 2012 by sac)
This has been going on for several days, at least, perhaps weeks:
The Ubuntu display manager periodically freezes when compiling 
sac programs. The mouse and keyboard go dead, and the taskbar
clock freezes, showing the same time. Some time later, typically
15-25 seconds, things take off again. The clock's second hand
jumps to the correct time.
The failure is fairly frequent and does not seem to be correlated
to any particular sac program.
I note that the system monitor also freezes, so I am unable to tell
what is going on with the CPUs and memory. 
I realize this isn't much help for fault isolation, but it is
a major pain in the butt if I'm trying to do other tasks
while running test suites.