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From: nospam@see.signature (Richard Maine)
Newsgroups: comp.lang.ada,comp.lang.fortran
Subject: Re: Bounds Check Overhead
Date: Fri, 26 May 2006 13:41:21 -0700
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Date: 2006-05-26T13:41:21-07:00
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glen herrmannsfeldt <gah@ugcs.caltech.edu> wrote:

> Richard Maine wrote:
> 
> > Likewise almost all compilers have the capability of detecting
> > most array bounds violations. That one tends to be mostly done at
> > run-time (some simple cases are caught at compile-time, but that's not
> > the usual cases),
> 
> I was not so long ago working on a Fortran program with the ever popular
> dimension (1) assumed size arrays.  (I believe it was written in 1990.)
> It seems the IBM XLF compiler, even with runtime bounds checking off,
> does compile time bounds checking.  A constant subscript of 2 is not 
> allowed with an assumed size array dimensioned (1).

That's exactly one of the simple cases I was talking about that are
sometimes caught. I've run into that one with old code. Might have even
been the same code, as I ran into it with a fairly widely used free
library code (perhaps fftpack, though I'm not sure of that). I was using
a different compiler though.

-- 
Richard Maine                    | Good judgement comes from experience;
email: last name at domain . net | experience comes from bad judgement.
domain: summertriangle           |  -- Mark Twain