Vax VMS C compiler

Guy Harris guy at sun.uucp
Thu Apr 25 17:30:39 AEST 1985


> Someone posted an article claiming that compiling the UNIX kernel
> and utilities with the VAX VMS C compiler resulted in a system which
> was 20% faster than the current unix (I assume 4.2 BSD).
> 
> I DON"T BELIEVE THIS!!!!!!  If they could get such a performance improvement
> their salespersons should be beating down our doors to try and convince us
> to run vaxen with ULTRIX rather than other brands.  Paying for ULTRIX as
> opposed to free 4.2 BSD would probably be worthwhile if we got a 20%
> improvement.
> 
> Possible reasons for the claim not being true: 

Possible reason for the claim being true but irrelevant to the merits of
ULTRIX vs. 4.2BSD:

1) ULTRIX uses the same compiler as vanilla 4.2BSD.  I believe this is the
case.  (Adapting the VAX/VMS C compiler may not be trivial; the VAX/VMS
and UNIX object module formats are quite different, and I don't think the
VAX/VMS compiler punts the object module format question the way most UNIX C
compilers do by generating assembly code).

	Guy Harris



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