Question

I tried the following code on both codepad.org and ideone.com:

char* ptr = new char;
free( ptr );

Yes, I know it’s undefined behavior, but I want to compile it and run it to see what happens.

Visual C++ 10 compiles it, but gcc which is used on the abovementioned sites says

error: expected constructor, destructor, or type conversion before ‘(’ token

Why wouldn’t this code compile with gcc and how could I make it compile?

Answer 1

This code indeed will not compile. You have to add main() call also.

#include <stdlib.h>

int main()
{
    char* ptr = new char;
    free( ptr );
    return 0;
}