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From: dewar@merv.cs.nyu.edu (Robert Dewar)
Subject: Re: Which language pays most? Smalltalk, not C++ nor Java.
Date: 1997/12/30
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Date: 1997-12-30T00:00:00+00:00
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Kaz says

<<That is absurd. Overflow invokes undefined behavior in C++. To check
for sign reversal, you would have to depend on a particular platform's
handling of overflow. On two's complement systems, overflow on addition or
subtraction can be detected by examining the most significant bit of the
result and those of the operands. This isn't true in general, however.

It's possible to determine whether a given operation will occur by
writing a test expression (or assertion) which itself does not invoke
overflow.
>>


Yes, it is possible, but gruesome, especially for multiplication. And rather
silly, since at the hardware level it is typically easy to detect overflow.
The lack of overflow detection in a language like C++ seems a clear and
annoying ommission (actually I had been told this was fixed in the latest
standard, but I guess that was false information). Anyway, the Ada approach
makes far more sense than appealing to highly dubious assertions!