Vax->11 C Cross-Compiler

[utzoo!decvax!ucbvax!unix-wizards]

>From obrien at RAND-UNIX Thu Oct 15 21:10:38 1981
	If you've got 4BSD or later running then you can just bring over
a compiler from an 11 and run it in compat mode.  We maintain our front-end
NCP that way.  Basically the following defines do it:

CFLAGS  = $(A) -O $(DEFS) $(INCL)
AS      = /usr/local/v7run -/usr/pdp11stuff /bin/as
CC      = /usr/local/v7run -/usr/pdp11stuff /bin/cc
LD      = -/usr/local/v7run -/usr/pdp11stuff /bin/ld
NM      = /usr/local/v7run -/usr/pdp11stuff /bin/nm
STRIP   = /usr/local/v7run -/usr/pdp11stuff /bin/strip

	The only really ugly thing about it is that v7run has to be suid
to root because the "chroot" system call is protected for security reasons.
So you probably have to protect it against all but sys group.

	We brought over all of the /bin, /usr/bin/, /usr/lib, etc. stuff
from the 11 with "tar" and put it under /usr/pdp11stuff.  v7run does a
chroot to there so all the 11 stuff thinks it's back home.  It works like
a champ.

        There are some fixes to compat mode that someone sent me to make
signals, floating point, etc. run right.  You can ask me for those, though
I haven't gotten around to testing them and I certainly don't want to
distribute them generally. "allegra!jdd at Berkeley" did the fixing; others on
unix-wizards should contact him/her directly.  None of the fixes are needed
to make compilations work (and even edits under "ed" if you want to go full
compat).