cc core dumping

[Jeff Russ]

Our 5840 running Ultrix 4.0 also dumps core occassionaly.  If I keep
repeating the cc command it will eventually compile okay.  It looks like
the logic for certain instructions in the machine needs to be warmed up for
a compile to succeed. (My old PDP8s at home sometimes have the same problem).

We currently see two different types of errors when it aborts:

	% cc -O frac.c
	Fatal error in: /usr/lib/cmplrs/cc/uopt Segmentation fault - core dumped

	% cc -O frac.c
	pid 11309 (uopt2.1) was killed on unaligned access, at pc 0x1a
	Fatal error in: /usr/lib/cmplrs/cc/uopt Bus error - core dumped

The last one occurrs less frequently.  The code compiles without any problems
on a 5200 running Ultrix 4.0.