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From: Brian Drummond <brian@shapes.demon.co.uk>
Newsgroups: comp.lang.ada
Subject: Re: Compiler checking of String lengths during assignment (Newbie
 Question)
Date: Sat, 10 Jan 2015 12:43:55 +0000 (UTC)
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On Sat, 10 Jan 2015 00:20:11 +0100, Stefan.Lucks wrote:

> On Fri, 9 Jan 2015, Simon Wright 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.
> 
> I believe, all three should generate a run-time error (most likely a
> Constraint_Error).

The FSF Gnat 4.9.1 (Debian package) compiles with warnings, and all three 
raise Constraint Error.

The first one reports "length check failed", 
the other two "range check failed".

We often hear that the FSF compiler "lags behind" the Libre one and maybe 
in some respects it does, but apparently, that doesn't mean it's always 
worse.

- Brian