Question

Possible Duplicate:
Can a local variable’s memory be accessed outside its scope?

double* weird( double a, double b )
{ 
    double c;
    c = pow( a + b, 0.5 );
    return &c;
}

It might be trivial for most of you guys, but I don’t see what could go wrong here.

Answer 1

This is very wrong because you are returning a pointer to a local variable.

When &c gets returned, the variable c whose scope is the function weird will be destroyed, thus giving you a pointer that points to a random area in your memory.
This is undefined behaviour.