Initializing a static pointer in C++

I have a class with a static member that's a pointer like so :

animation.h

class Animation
 {
 public:
     Animation();
     static QString *m;
 
 };
 

animation.cpp

#include "animation.h"
 
 QString* Animation::m = 0;
 
 Animation::Animation()
 {
 }
 

When I try to initialize that 'm' pointer from another class like so :

Animation::m = new QString("testing");
 

It works.

But when I do it this way :

QString x("Testing");
 Animation::m = &x;
 

The program crashes.

What is wrong with this second method ?

Also I would like to have that static pointer as private so I can make static getter and setter functions to it. The setter should use the second method as the 'x' will come in a parameter so I'm stuck.

Thanks for any help!

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