本当だ、なんだこれは…。申し訳ないです、元はこんなのでした。
class Hoge{ //Hoge.h--------------------------------
　HogeState* state;
public:
　Hoge(){ state = new HogeState; }
　void changeState( HogeState* new_state ){ delete state; state = new_state; }
　void foo(){ state->foo( this ); }
　void foo2(){ state->foo2( this ); }
};
class Hoge; //HogeState.h---------------------------
class HogeState{
　int ahe;
public:
　void foo( Hoge* hoge );
　void foo2( Hoge* hoge );
};
#include "HogeState.h" //HogeState.cpp---------------
#include "Hoge.h"
void HogeState::foo( Hoge* hoge ){
　hoge->changeState( new HogeState );
　ahe = 777;
}
void HogeState::foo2( Hoge* hoge ){
　ahe = 888;
　hoge->changeState( new HogeState );
}
#include "HogeState.h" //main.cpp--------------------
#include "Hoge.h"
int main(){
　Hoge hoge;
　hoge.foo(); hoge.foo2();
}