runtime_error was not declared in this scope for g++ 4.1.2

Question

The same code is working fine on gcc 4.5.2 but when trying to compile it on gcc 4.1.2, I get the error ‘runtime_error’ was not declared in this scope.

I do

Answer 1

Do you have using namespace std; or using std::runtime_error;? If not, then you need to fully qualify the name and use std::runtime_error rather than just runtime_error.