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From: Jeffrey Carter <spam.jrcarter.not@spam.not.acm.org>
Newsgroups: comp.lang.ada
Subject: Re: Compiler checking of String lengths during assignment (Newbie
 Question)
Date: Fri, 09 Jan 2015 17:18:40 -0700
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Date: 2015-01-09T17:18:40-07:00
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On 01/09/2015 03:50 PM, isaac1.0@gmail.com wrote:
> 
> The first 2 cases produces an error during the build, as expected, because
> Head is known to be length of 5 and I'm assigning something of a different
> length.

They might produce warnings, but not errors, unless you've told the compiler to
treat warnings as errors.

> The 3rd assignment there does NOT produce an error, no warning no nothing
> even though this clearly violates the same check.

Have you tried compiling with -gnatwa?

> What does happen is that at runtime the execution is incorrect. It doesn't
> even terminate in a horrible disaster (which would be preferable). The full
> program actually just reads a text file (for now) and in this case because
> the assigned length is incorrect, it just reads a few lines then bails
> claiming unable to read the text file.

Do you have an exception handler?

> Aren't Ada compilers supposed to prevent stupid errors like this? Or is there
> some user stupidity here that I'm not seeing...?

Unless you give us a complete program, the options used when building it, the
exact messages output when run, and what you expected the result of running it
to be, we can't tell.

-- 
Jeff Carter
"Sons of a silly person."
Monty Python & the Holy Grail
02