Callback: comparision fails

[0xc0170]

Description

• Type: Bug
• Priority: Major

How to reproduce:

#include "mbed.h"
#include "rtos.h"

void donothing()
{

}

int main()
{
    Callback<void()> func1;
    Callback<void()> func2;
    func1 = donothing;
    func2 = donothing;
    if (func1 != func2) {
        error("Should be equal");
    }
}

I had similar code in one patch that started failing. I was looking for API in Callback that would check if Callback was assigned the same function (the default one), the only way there I found was to use comparision operators. Those however fail, as shown above.

What I noticed that when those two objects are compared, _obj is always different. Seems to me that generate() method does not generate properly callback - does not pollute all members?

@geky @pan-

[0xc0170]

Also operator== seems to be broken, Callback is non-POD and we use memcmp.

[geky]

Thanks for adopting the workaround, here's a quick fix for the Callback class: #5027