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I am a beginner openGL programmer, learning openGL from a TouTube tutorial. I did exactly the same steps as the tutorial stated. I get this exception:

Unhandled exception in 0x7732F949 in OpenGL.exe: 0xC0000005: access violation while using the path 0x00000000. here's the code:
#include <GL/glew.h>
#include <GLFW/glfw3.h>
#include <iostream>

static unsigned int CompileShader(unsigned int type, const std::string& source)
{
    unsigned int id = glCreateShader(type);
    const char* src = source.c_str();
    glShaderSource(id, 1, &src, nullptr);
    glCompileShader(id);

    int result;
    glGetShaderiv(id, GL_COMPILE_STATUS, &result);
    if (result == GL_FALSE) {
        int length;
        glGetShaderiv(id, GL_INFO_LOG_LENGTH, &length);
        char* message = (char*)alloca(length * sizeof(char));
        glGetShaderInfoLog(id, length, &length, message);
        std::cout << "Failed to compile" << (type == GL_VERTEX_SHADER ? "vertex" : "fragment") << "shader!";
        std::cout << message << std::endl;
        glDeleteShader(id);
        return 0;
    }

    return id;
}
static int CreateShader(const std::string& vertexShader, const std::string& fragmentShader)
{
    unsigned int program = glCreateProgram();
    unsigned int vs = CompileShader(GL_VERTEX_SHADER, vertexShader);
    unsigned int fs = CompileShader(GL_FRAGMENT_SHADER, fragmentShader);

    glAttachShader(program, vs);
    glAttachShader(program, fs);
    glLinkProgram(program);
    glValidateProgram(program);

    glDeleteShader(vs);
    glDeleteShader(fs);
    return program;
}



int main(void)
{
    GLFWwindow* window;

    /* Initialize the library */
    if (!glfwInit())
        return -1;


    /* Create a windowed mode window and its OpenGL context */
    window = glfwCreateWindow(640, 480, "Hello World", NULL, NULL);
    if (!window)
    {
        glfwTerminate();
        return -1;
    }

    /* Make the window's context current */
    glfwMakeContextCurrent(window);
    if (glewInit != GLEW_OK) {
        std::cout << "error! unhandled exception" << std::endl;
    }

    float positions[6] = {
          0.5, 0.0,
         -0.5, 0.0,
          0.0, 0.8
    };

        unsigned int buffer;
        glGenBuffers(1, &buffer);
        glBindBuffer(GL_ARRAY_BUFFER, buffer);
        glBufferData(GL_ARRAY_BUFFER, sizeof(positions), positions, GL_STATIC_DRAW);
        glEnableVertexAttribArray(0);
        glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, 2 * sizeof(float), 0);


        std::string vertexShader =
            "#version 330 core\n"
            "\n"
            "layout(location = 0) out vec4 color;\n"
            "\n"
            "void main()\n"
            "{\n"
            "gl_Postion = position\n"
            "}\n";
        std::string fragmentShader =
            "#version 330 core\n"
            "\n"
            "layout(location = 0) in vec4 position;\n"
            "\n"
            "void main()\n"
            "{\n"
            "color = vec4(1.0, 0.0, 0.0, 1.0)\n"
            "}\n";

        unsigned int shader = CreateShader(vertexShader, fragmentShader);
        glUseProgram(shader);

    /* Loop until the user closes the window */
    while (!glfwWindowShouldClose(window))
    {
        /* Render here */
        glClear(GL_COLOR_BUFFER_BIT);
        glDrawArrays(GL_TRIANGLES, 0, 3);

        /* Swap front and back buffers */
        glfwSwapBuffers(window);

        /* Poll for and process events */
        glfwPollEvents();
    }

    glfwTerminate();
    return 0;
}
  • 1
    Your issue is NOT a Visual Studio issue, your issue is a programming issue, I have voted to migrate this question to Stack Overflow. – Ramhound Jul 23 at 18:10

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