glGetError() test macro

glerrcheck.h

// A macro I wrote a few years back to assist in checking OpenGL error codes.
// Add to a .h or at the top of your implementation file:

#define GLERR do {\
        GLuint glerr;\
        while((glerr = glGetError()) != GL_NO_ERROR)\
            fprintf(stderr, "%s:%d glGetError() = 0x%04x", __FILE__, __LINE__, glerr);\
    } while (0)

// Sprinkle in "GLERR;" after failure-prone OpenGL calls.