From:	Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: GCC warning - incompatible pointer type
Date:	10 Feb 2003 10:18:07 GMT
Organization:	Aachen University of Technology (RWTH)
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References:	<200302081532 DOT h18FW3u24717 AT speedy DOT ludd DOT luth DOT se>
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ams AT ludd DOT luth DOT se wrote:

> Evidently the C idea of every pointer is compatible to "void *"
> doesn't extend to "void *"s in functions.

More precisely, it doesn't extend to function pointers.  Pointers to
functions are quite strict in their compatibility requirements.  It's
best to assume that you should never, ever, cast a function pointer,
or use a function pointer of a given type where a function pointer of
*any* other type is asked for.

> Alternatively is should be a safe to use strcmp directly (but don't
> hold me to this in court), so a functioncast (if possible) would make
> the compiler quiet.

That cast would be a placebo solution.  It solves exactly none of the
problems that the language makers saw, and which made them require
this particular warning in the definition of standard C.

-- 
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.

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