rcs/diff, and gcc vs cc

[Alma G. Sorensen]

I'm trying to get rcs working under 2.0.

It tells me rcs needs a diff that does -n or something, which
from the man page A/UX's diff doesn't do. Fine. Gnu's does.

However, when I try to compile gnu's diff-1.15, I get errors:

        gcc -O -DUSG -DSYSV -c diff.c
diff.c: In function compare_files:
diff.c:504: `S_IFDIR' undeclared (first use this function)
diff.c:504: (Each undeclared identifier is reported only once
diff.c:504: for each function it appears in.)
diff.c:504: `S_IFMT' undeclared (first use this function)
Make: *** Error: Update of diff.o terminated with exit code 1
 

Strangely, if I use cc instead of gcc, things compile fine!

I must have gcc installed wrong...What could I be missing?

Thanks,
Greg Sorensen
sorensen at athena.mit.edu