GL functions are located but never called

I have encountered a very strange issue on Windows where functions are located (or at least searched for) by wglGetProcAddress but never seem to be called. I first encountered this problem when trying to create some textures but seems to be a much larger problem.

Here is a fairly minimal test case which illustrates the problem.

module Main where

import Graphics.Rendering.OpenGL
import Graphics.UI.GLUT

-- To simplify loading data into textures
import Graphics.GLUtil
import Graphics.GLUtil.JuicyTextures

main :: IO ()
main = do
    -- Setup
    initialDisplayMode $= [DoubleBuffered]
    initialWindowSize $= (Size 600 600)
    (progname, args) <- getArgsAndInitialize
    wnd <- createWindow "Test case"

    -- No GL functions are actually called in this next block for some reason (except glActiveTexture)
    clearColor $= Color4 0 0 0 0
    textureObject <- genObjectName
    readTexInfo "texture.png" $ reloadTexture textureObject
    activeTexture $= TextureUnit 0
    textureBinding Texture2D $= Just textureObject

    -- Print the texture object to show that we did get a number back
    print textureObject

    -- Run the program
    displayCallback $= display
    putStrLn "Running loop"
    mainLoop

display :: IO ()
display = do
    clear [ColorBuffer]
    -- Keeping it simple. I get the same result using shaders and VBOs
    -- No GL functions are ever called in here either
    renderPrimitive Quads $ do
        texCoord (TexCoord2 0 0 :: TexCoord2 GLdouble)
        vertex (Vertex2 (-1) 1 :: Vertex2 GLdouble)
        texCoord (TexCoord2 1 0 :: TexCoord2 GLdouble)
        vertex (Vertex2 1 1 :: Vertex2 GLdouble)
        texCoord (TexCoord2 1 1 :: TexCoord2 GLdouble)
        vertex (Vertex2 1 (-1) :: Vertex2 GLdouble)
        texCoord (TexCoord2 0 1 :: TexCoord2 GLdouble)
        vertex (Vertex2 (-1) (-1) :: Vertex2 GLdouble)
    swapBuffers

This should simply load a texture and display it, but all I see is a white screen. I have executed this program under gDEBugger and the following is a log of all the OpenGL-related function calls it saw:

wglGetProcAddress(glClearColor) 
wglGetProcAddress(glGenTextures) 
wglGetProcAddress(glBindTexture) 
wglGetProcAddress(glTexImage2D) 
wglGetProcAddress(glActiveTexture) 
glActiveTexture(GL_TEXTURE0) 
wglGetCurrentContext() 
wglGetCurrentDC() 
wglGetCurrentContext() 
wglGetCurrentDC() 
glViewport(0, 0, 600, 600) 
wglGetCurrentContext() 
wglGetCurrentDC() 
wglGetCurrentContext() 
wglGetCurrentDC() 
wglGetProcAddress(glClear) 
wglGetProcAddress(glBegin) 
wglGetProcAddress(glTexCoord2d) 
wglGetProcAddress(glVertex2d) 
wglGetProcAddress(glEnd) 
wglSwapBuffers(0x4B012FAB)

As you can see, while there are a couple of GL functions executed, most of them aren't. What's weirder still is that even though glGenTextures never seems to be executed, textureObject still seems to get a value.

It seems to me like the functions aren't being located correctly, but if that's the case, where does the value of textureObject come from? And shouldn't it be erroring instead?

Any idea what's going on here?

GHC 7.6.3 OpenGLRaw 1.4 OpenGL 2.9 GLUT 2.5

haskell-opengl / OpenGLRaw

GL functions are located but never called #20