Static error

[Airslash]

Eum, ok this might be a long post, but I'll try to keep it as short as possible...

Firs the error in the console during the compile :

Code: Select all

g++ -LC:\Users\Arne\workspace\bluedragoon\lib\win32 -obluedragoon.exe sound\src\soundengine.o render\src\renderengine.o render\src\loginmanager.o render\src\loginbuttonevent.o core\src\status.o core\src\skill.o core\src\characterfactory.o core\src\character.o core\src\battlemanager.o bin\main.o -lIrrlicht -lmingw32 -lSDL -lSDLmain -lSDL_mixer
render\src\loginbuttonevent.o: In function `ZN3irr4core12irrAllocatorIcE12internal_newEj':
C:/Users/Arne/workspace/bluedragoon/include/irrlicht/irrAllocator.h:(.bss+0x0): multiple definition of `render::LoginManager::_instance'
render\src\loginmanager.o:C:/Users/Arne/workspace/bluedragoon/include/irrlicht/irrAllocator.h:(.bss+0x0): first defined here
Build error occurred, build is stopped
Time consumed: 2911  ms. 

The mentioned file causing the problem:

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#ifndef LOGINMANAGER_H_
#define LOGINMANAGER_H_
#include <irrlicht.h>

namespace render {
	class LoginManager {
		private:
			irr::IrrlichtDevice* device;
			irr::video::IVideoDriver* video;
			irr::scene::ISceneManager* scene;
			static LoginManager* _instance;
			
		public:
			static LoginManager* instance();
			
			void createDevice(irr::IEventReceiver* reciever, irr::video::E_DRIVER_TYPE deviceType=irr::video::EDT_OPENGL, const irr::core::dimension2d<signed int>& windowsize=irr::core::dimension2d<signed int>(640, 480), unsigned int bitdepth=16, bool fullscreen=false, bool stencilbuffer=false, bool vsync=false);
			void render();
			
			irr::gui::IGUIEnvironment* getGUIEnvironment();
			
			void setEventReciever(irr::IEventReceiver* reciever);
		protected:
			LoginManager();
			~LoginManager();
	};
	
	// Initialze the pointer variable of the class.
	// Only the pointer, not the class.
	LoginManager* LoginManager::_instance = NULL;
}

#endif /*LOGINMANAGER_H_*/

and the implementation

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#include "../loginmanager.h"
using namespace render;

LoginManager::LoginManager() {
	this->device = 0;
	this->scene = 0;
	this->video = 0;
}

LoginManager* LoginManager::instance() {
	if(NULL == _instance) {
		_instance = new LoginManager();
	}
	
	return _instance;
}

irr::gui::IGUIEnvironment* LoginManager::getGUIEnvironment() {
	return this->device->getGUIEnvironment();
}

void LoginManager::setEventReciever(irr::IEventReceiver* reciever) {
	this->device->setEventReceiver(reciever);
}

void LoginManager::createDevice(irr::IEventReceiver* receiver, irr::video::E_DRIVER_TYPE deviceType, const irr::core::dimension2d<signed int>& windowsize, unsigned int bitdepth, bool fullscreen, bool stencilbuffer, bool vsync) {
	this->device = irr::createDevice(deviceType, windowsize, bitdepth, fullscreen, stencilbuffer, vsync, receiver);
	this->device->setWindowCaption((wchar_t*)"BlueDragoon Login");
	this->video = this->device->getVideoDriver();
	this->scene = this->device->getSceneManager();
}

void LoginManager::render() {
	// TODO: Implement render method
}

LoginManager::~LoginManager() {
	this->device->drop();
}

Could someone explain to me where it's going wrong with that static _instance call ?

[rogerborg]

Code: Select all

   // Initialze the pointer variable of the class.
   // Only the pointer, not the class.
   LoginManager* LoginManager::_instance = NULL; 

This must be defined once and only once. Put it in the .cpp file rather than the header.

[Airslash]

but doesn't the #ifndef statement at the head of the header prevent double initialization ?

And I have three like these classes, but only this one is causing problems.

[rogerborg]

but doesn't the #ifndef statement at the head of the header prevent double initialization ?

No. It only stops inclusion more than once during compilation of each source file; it doesn't stop it being included by multiple source files and therefore defined multiple times at link time.

And I have three like these classes, but only this one is causing problems.

The others are only included by one source file.

[Airslash]

ok i'll make the changes then.
Thanks for pointing it out

[Airslash]

it works, thanks for the help