[HOpenGL] -O strangeness

[Robert Vollmert]

--wac7ysb48OaltWcw
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline

Hello,

I've been experimenting with HOpenGL a little, and have run into
strange behaviour when compiling with -O. In particular, while things
work as expected when compiling normally, if I compile the following
module with -O, drawLine' appears to scale the line by 2, while
drawLine works as before.

module Lines where

import GL

drawLine = do
    pushMatrix
    beginEnd Lines . sequence_ . map vertex $
	         [ Vertex2 0 0, Vertex2 0 (1::GLfloat) ]
    popMatrix

drawLine' = do
    pushMatrix
    scale 1 1 (1::GLfloat)
    beginEnd Lines . sequence_ . map vertex $
	         [ Vertex2 0 0, Vertex2 0 (1::GLfloat) ]
    popMatrix


This was tested using the attached program. I'm using HOpenGL-1.01
with the recent patch, and a ghc from CVS which is about a week old.
When compiling Lines.hs with -O, I get

/tmp/ghc14725.hc: In function `s8Wy_ret':
/tmp/ghc14725.hc:474: warning: implicit declaration of function `glScalef'

Also, if I actually compile the test program with -O, it doesn't
display anything.


--wac7ysb48OaltWcw
Content-Type: text/plain; charset=us-ascii
Content-Disposition: attachment; filename="Test2.hs"

import GL
import GLU
import GLUT
import System(ExitCode(..), exitWith)
import Lines

display :: DisplayAction
display = do
    clear [ ColorBufferBit ]
    loadIdentity
    color (Color3 1.0 0.0 (0.0::GLfloat))
    translate $ Vector3 1 1 (0::GLfloat)
    drawLine
    translate $ Vector3 1 0 (0::GLfloat)
    drawLine'
    flush

myInit :: IO ()
myInit = do
    clearColor (Color4 0 0 0 0)
    matrixMode Projection
    loadIdentity
    ortho 0 3 0 4 (-1) 1
    matrixMode Modelview

keyboard :: KeyboardAction
keyboard '\27' _ = exitWith ExitSuccess
keyboard 'q'   _ = exitWith ExitSuccess

main :: IO ()
main = do
    GLUT.init Nothing
    createWindow "mine test" (return ()) [ GLUT.Single, GLUT.Rgb ] 
		 Nothing
		 (Just (WindowSize 320 240))
    myInit
    keyboardFunc (Just keyboard)
    displayFunc display
    mainLoop

--wac7ysb48OaltWcw--