Message-ID: <352F9281.4822E430@algroup.co.uk>
Date: Sat, 11 Apr 1998 16:55:45 +0100
From: Ben Laurie <ben@algroup.co.uk>
Organization: A.L. Digital Ltd.
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Subject: Re: [PATCH] Resolve BUILD warnings under ULTRIX/mips (take 3)
References: <Pine.LNX.3.96dg4.980410164817.28897K-100000@twinlark.arctic.org>
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Dean Gaudet wrote:
> 
> Nah casts aren't ever safe ;)
> 
> Need I drag out the crypto example again?  Such an innocent cast... such a
> devastating effect.  The code looked something like this:
> 
>     tmp = (unsigned)gen_salt;
> 
> when it was supposed to be:
> 
>     tmp = (unsigned)gen_salt();
> 
> A world of difference between the two of course.  But the cast hides it.
> I forget what code it was in, but that's a real life mistake.
> 
> And C++ doesn't help it.

That's where you are wrong:

	tmp=static_cast<unsigned>(gen_salt);

catches this mistake:

Test7.cpp(155) : error C2440: 'static_cast' : cannot convert from 'int
(__cdecl *)(void)' to 'unsigned int'
This conversion requires a reinterpret_cast, a C-style cast or
function-style cast

It does irritate me that people are so prejudiced against something they
don't even know how to use.

(BTW, I tested this on VC++ and g++. g++ didn't work (version 2.7.x)).

Cheers,

Ben.

-- 
Ben Laurie            |Phone: +44 (181) 735 0686|  Apache Group member
Freelance Consultant  |Fax:   +44 (181) 735 0689|http://www.apache.org
and Technical Director|Email: ben@algroup.co.uk |
A.L. Digital Ltd,     |Apache-SSL author    http://www.apache-ssl.org/
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