activate RTTI in c++

Question

Can anybody tell me how to activate RTTI in c++ when working on unix. I heard that it can be disabled and enabled. on my unix environment,how could i check whether RTTI is enabled or disabled?

I am using the aCC compiler on HPUX.

Answer 1

Are you using g++ or some other compiler?

In g++ RTTI is enabled by default IIRC, and you can disable it with -fno-rtti. To test whether it is active or not use dynamic_cast or typeid

UPDATE

I believe that HPUX's aCC/aC++ also has RTTI on by default, and I am unaware of a way to disable it. Check your man pages.

Answer 2

gcc has it on by default. Check if typeid(foo).name() gives you something useful.

#include <iostream> #include <typeinfo>  int main() {  std::cout << typeid(int).name() << std::endl;  return 0; } 

Without RTTI you get something like:

foo.cpp:6: error: cannot use typeid with -fno-rtti