[comp.unix.xenix] alloca for 286 xenix

ronald@robobar.co.uk (Ronald S H Khoo) (03/05/90)

In article <955@chinacat.Lonestar.ORG> chip@chinacat.Lonestar.ORG (Chip Rosenthal) writes:
> Given that the default stack
> size is 0x1000 bytes, and gnu programs tend to alloca() like crazy, it
> isn't surprising that you can't get very far.
Arnold Robbins will want you to say _Some_ GNU programs :-)
But you're right. :-(
 
> I haven't looked at the source close enough to see how much gnu diff beats
> on alloca(), but you might want to fixhdr(C) the executable to make the
> stack bigger.

I suspect that it might be more useful to  use Doug Gwyn's C alloca emulation
instead, as distributed with some GNU programs, including gawk (GNU Awk).
This uses malloc to emulate alloca and should not be too much of a hit for
grep.  I'm surprised that any fixed stack implementation would dare put a
'real' alloca in the ?libc.a at all.

Disclaimer: I don't have 286 xenix running on anything anymore, so I have
no idea how relevant this may be.  I certainly don't remember having alloca
when I _did_ use 286 xenix.

-- 
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