undefined reference to `SDL_CreateWindow' [duplicate]

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• Problems importing libraries to my c++ project, how to fix this? 2 answers

i working on code to create SDL window but when i run this code i get this error i using code block IDE and gcc compiler that's my code error in line 23

#include "maingame.h"

maingame::maingame()
{
    _window = nullptr;
    _screenWidth = 1024;
    _screenHeight = 768;

}


maingame::~maingame()
{

}

 void maingame::run() {
      initSystems();

 }
 void maingame::initSystems() {
     SDL_Init(SDL_INIT_EVERYTHING);
     _window = SDL_CreateWindow("game_engine", SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED, _screenWidth, _screenHeight, SDL_WINDOW_OPENGL);


 }