Ultrix 4.1/F77 C compiler 2.0 2.1 version confusion

[Ian! D. Allen [CGL]]

"cc -V" tells me I have the 2.0 C compiler on my DS5400 running Ultrix
4.1.  When I installed F77, it added a "cc2.1" command and directory to
/usr/lib/cmplrs.  But the change date on the stuff that makes up the 2.1
compiler makes the 2.1 compiler *older* than the 2.0 compiler, e.g. some
"what" output:

/usr/lib/cmplrs/cc2.0/ccom2.0
	fseek.c 3.2     (ULTRIX)        6/6/90
	ftell.c 3.2     (ULTRIX)        6/6/90
	[...etc...]

/usr/lib/cmplrs/cc2.1/ccom2.1
	fseek.c 2.3     (ULTRIX)        2/6/90
	ftell.c 2.2     (ULTRIX)        2/6/90
	[...etc...]

This is counter-intuitive.  I thought higher version numbers meant
more recent products?  Indeed, the cc2.1 compiler doesn't even
understand the "-V" option:

    # cc2.1 -V
    cc2.1: Error: no source, object or ucode file specified

Can anyone explain what is going on, and which compiler is the favoured one?
-- 
-IAN! (Ian! D. Allen) idallen at watcgl.uwaterloo.ca idallen at watcgl.waterloo.edu
 [129.97.128.64]  Computer Graphics Lab/University of Waterloo/Ontario/Canada