Why C++ virtual function defined in header may not be compiled and linked in vtable?
- by 0xDEAD BEEF
Situation is following. I have shared library, which contains class definition -
QueueClass : IClassInterface
{
virtual void LOL() { do some magic}
}
My shared library initialize class member
QueueClass *globalMember = new QueueClass();
My share library export C function which returns pointer to globalMember -
void * getGlobalMember(void) { return globalMember;}
My application uses globalMember like this
((IClassInterface*)getGlobalMember())->LOL();
Now the very uber stuff - if i do not reference LOL from shared library, then LOL is not linked in and calling it from application raises exception. Reason - VTABLE contains nul in place of pointer to LOL() function.
When i move LOL() definition from .h file to .cpp, suddenly it appears in VTABLE and everything works just great.
What explains this behavior?! (gcc compiler + ARM architecture_)
