CODEWITHSUNDEEP
c++
PeerPandit
PeerPandit

Reputation: 309

Default Constructor Recursion Crash

/*The following program seems to mysteriously enter recursion even though there is none in sight. Compiler: g++ (Ubuntu 4.4.3-4ubuntu5.1) 4.4.3 Machine: x86 OS: Ubuntu 10.04 64-bit

*/

    #include<iostream>
    using namespace std;

    class Test
    {
    public:
      Test ():x(9)
      {
        cout << " Test::Test\n";
        Test (x);
      }
      Test (int a)
      {
        cout << " Test::para\n";
      }
    private:
            int x;
    };


int main(void)
{
 Test a;
return 0;
}

Why is this?

Upvotes: 2

Views: 205

Answers (2)

Konrad Rudolph
Konrad Rudolph

Reputation: 545963

You cannot call other constructors like that in C++. But starting with C++11, you can forward constructor calls in the initialiser list:

class Test {
public:
    Test (): Test(9) {
        cout << " Test::Test\n";
    }

    Test (int a) : x(a) {
        cout << " Test::para\n";
    }

private:
    int x;
};

See Wolfgang’s answer for an explanation of why your code crashes.

Upvotes: 2

wolfgang
wolfgang

Reputation: 4953

Test (x);

is parsed as

Test x;

... not as a constructor call. You can also write

Test (y);

and get the same behaviour.

Upvotes: 9

Related Questions