[comp.unix.microport] Conquer 4.0 on SysV/AT

stever@tree.UUCP (Steve Rudek) (07/25/89)

In article <34@jhereg.Minnetech.MN.ORG>, dab@jhereg.Minnetech.MN.ORG (David A. Bright) writes:
> 
> Can anybody explain this message from the C compiler under System V/AT?
> "npc.c", line 393: compiler error: segment overwrite - get help
> *** Error code 1
> 
You probably know by now that this type of error message is quite common
when trying to get source with complicated expressions to compile under
SysV/AT.  The work around is to break up the complicated expressions
--things such as deeply nested && and || conditionals--and replace things
like A+=B with A=A+B.

I spent many hours working through conquer 4.0, though, only to find that I
could compile it but not run it -- it uses a huge array and, of course, Sys
V/AT doesn't support huge arrays.  In some other cases it has been possible
to kludge around the need for a huge array by implementing a kludgy virtual
memory.  However, conquer's references to the huge array are pervasive and
it seemed an extensive rewrite of the code would be required; I backburnered
it until the year after next :-).
 
(1) Does anyone have more ambition than I?  That is, is anyone already
working on a conquer 4.0 hack?
 
(2) Why did Microport have 'no plans' to support the huge memory model?
Would it have been that big a deal for them to add that support?

(3) Has anyone worked on a generalized hack to fake virtual memory or, more
modestly, huge arrays?
-- 
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Steve Rudek  {ucbvax!ucdavis!csusac OR ames!pacbell!sactoh0} !tree!stever

debra@alice.UUCP (Paul De Bra) (07/26/89)

In article <344@tree.UUCP> stever@tree.UUCP (Steve Rudek) writes:
>...
>(3) Has anyone worked on a generalized hack to fake virtual memory or, more
>modestly, huge arrays?

The source for compress has a hack for huge arrays. It was introduced for
simulating a huge array back in the days when Xenix didn't have a huge
model. Xenix now no longer needs this hack but uPort does.

Paul.
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