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C++ - OpenGL modifies variable without being explicitly told to?

How to C++ - OpenGL modifies variable without being explicitly told to

Hi, I'm trying to write a program with OpenGL using c++, glad and glfw, but I've encountered a problem I cannot wrap my head around.

main.cpp

#include <glad/glad.h>
#include <GLFW/glfw3.h>
#include <iostream>

#define SCR_WIDTH 1280
#define SCR_Height 720

int main() {
    GLFWwindow* window = init();

    unsigned int VAO, VBO, EBO;

    glGenVertexArrays(1, &VAO);
    glGenBuffers(1, &VBO);
    glGenBuffers(N_EBOS, &EBO);

    //load vertices etc..
    
    while (!glfwWindowShouldClose(window)) {
        glfwSwapBuffers(window);

        // Render stuff...

        glfwPollEvents();
    }

    glfwTerminate();

    return 0;
}

Basically if I remove glGenBuffers(N_EBOS, &EBO); it all works fine, but when I add that line, and N_EBOS is 15 or more, the program segfaults at the glfwWindowShouldClose(window) line. After using a debugger I found that after the glGenbuffers(N_EBOS, &EBO); is run, the window variable changes value, and I can't figure out how or why it does that. I also made a gif to show the problem better:

For more contex, this is the init(); function:

GLFWwindow* init() {
    glfwInit();
    glfwWindowHint(GLFW_CONTEXT_VERSION_MAJOR, 3);
    glfwWindowHint(GLFW_CONTEXT_VERSION_MINOR, 3);
    glfwWindowHint(GLFW_OPENGL_PROFILE, GLFW_OPENGL_CORE_PROFILE);

#ifdef __APPLE__
    glfwWindowHint(GLFW_OPENGL_FORWARD_COMPAT, GL_TRUE);
#endif


    GLFWwindow* window = glfwCreateWindow(SCR_WIDTH, SCR_HEIGHT, "Thing", nullptr, nullptr);
    if (window == nullptr) {
        std::cout << "Failed to create GLFW window" << std::endl;
        glfwTerminate();
        exit(1);
    }
    glfwMakeContextCurrent(window);

    if (!gladLoadGLLoader((GLADloadproc) glfwGetProcAddress)) {
        std::cout << "Failed to initialize GLAD" << std::endl;
        exit(1);
    }
    glViewport(0, 0, SCR_WIDTH, SCR_HEIGHT);
    return window;
}

So what could be cause, and what could be a solution? I tried searching online but to no avail.

I thought this could be some sort of buffer overflow, but I cannot see where this could happen. Also if it helps I'm using Clion with CMake, CPP 23, OpenGL 3.3 and Arch Linux.

Solution:

If N_EBOS is 15, more than 1 that is, then the second argument of glGenBuffers must point to the first item of the array of at least this size, otherwise you'll get a buffer overflow.

::std::array<GLuint, N_EBOS> ebos{};
::glGenBuffers(ebos.size(), ebos.data());

And don't forget to call ::glGetError to figure out whether call succeeded.