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From: Paolo Bonzini <paolo.bonzini@polimi.it>
Reply-To: bonzini@gnu.org
To: gcc@gcc.gnu.org
Subject: Re: Turning off C++ casting?
Date: Thu, 20 Feb 2003 10:05:00 -0000
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> But if I'm iterating over lots of
> objects, I'd like to get rid off the cost of dynamic_cast when I know
> for sure the objects will always be of this type.

assert and the pointer version of dynamic_cast are your friends if you don'=
t=20
want #ifdefs.

  assert (dynamic_cast<ExtendedObject*>(&baseObj) !=3D NULL);
  ExtendedObject& obj =3D *reinterpret_cast<ExtendedObject*>(&baseObj);

> What I want to know is whether GCC allows you to optimize
> 'dynamic_cast'ing: gcc -fno_dynamic_cast ....  I don't think gcc has
> such a switch.

Maybe -fno-rtti (along with disabling much more)?

Paolo