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Date: Thu, 2 Dec 2004 16:35:45 +0300
From: Sergey Zaharchenko <doublef@tele-kom.ru>
To: Richard Tobin <richard@inf.ed.ac.uk>
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Subject: Re: gcc violates const-ness of variable?
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<Figured Rob would never get an off-list reply because of an invalid
address... sending the reply here>

On Thu, Dec 02, 2004 at 11:27:24AM +0000,
 Richard Tobin probably wrote:
> > IIRC "const" does not exist in *standardized* C...
>=20
> No, it exists in both C89 and C99.  But the error is in your program,
> not the compiler.  "const" in C is a promise that you do not change
> the value, and you break that promise.
>=20
> It may be different in C++, I don't know.

In C, your promise is a promise to yourself only. In C++, the compiler
believes your promise and optimizes out the variable so that
printf(...,n) becomes printf(...,0). C++ is intendedly so `gullible' to
make more aggressive optimizations (like this) possible.

Try turning off optimizations for g++ to see if that `helps', but the
code is not valid C++ anyway.

HTH,

--=20
DoubleF
A LISP programmer knows the value of everything, but the cost of
nothing.

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