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From: Marco van de Voort <marcov@toad.stack.nl>
Newsgroups: comp.lang.pascal.borland
Subject: Re: longint and/or overflow bug?
Date: Wed, 31 Oct 2012 10:11:49 +0000 (UTC)
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Xref: csiph.com comp.lang.pascal.borland:133

On 2012-10-31, Marco van de Voort <marcov@toad.stack.nl> wrote:
> On 2012-10-30, Jim Leonard <mobygamer@gmail.com> wrote:
>>
>> var
>>   l:longint;
>>   w1,w2:word;
>>
>> begin
>>   w1:=val1; w2:=val2;
>>   l:=w1 * w2; {Throws runtime 215 "arithmetic overflow" if $Q+}
>
> typing:
> longint :=word * word

> Pascal rule is afaik that an expression is evaluated in (at least?) the
> combined range of the operands.  Which is word.

Hmm, thinking of it, in Pascal the above is impossible, since range(word)
is not a subset of range(integer). Those are special yet again.

Still the behaviour is normal and consistent in the Borland lines and
compatibles.