I keep on getting segmentation fault each time I load fourth texture - what type of texture, I mean filename, does not matter. I checked value of GL_TEXTURES_STACK_SIZE which turned out to be 10 so quite more than 4, isn't it?

Here're code fragments:

funciton to load texture from png

static GLuint gl_loadTexture(const char filename[]) {
    static int iTexNum = 1; 
    GLuint texture = 0;
    img_s *img = NULL;

    img = img_loadPNG(filename);
    if (img) {
        glGenTextures(iTexNum++, &texture);
        glBindTexture(GL_TEXTURE_2D, texture);
        glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
        glTexImage2D(GL_TEXTURE_2D, 0, img->iGlFormat, img->uiWidth, img->uiHeight, 0, img->iGlFormat, GL_UNSIGNED_BYTE, img->p_ubaData);
        img_free(img); //it may cause errors on windows
    } else printf("Error: loading texture '%s' failed!\n", filename);

    return texture;
}

actual loading

static GLuint textures[4];

static void gl_init() {
    (...) //setting up OpenGL

    /* loading textures */
    textures[0] = gl_loadTexture("images/background.png");
    textures[1] = gl_loadTexture("images/spaceship.png");
    textures[2] = gl_loadTexture("images/asteroid.png");
    textures[3] = gl_loadTexture("images/asteroid2.png"); //this is causing SegFault no matter which file I load!
}

Any ideas?

Problem is present on both Linux and Windows.