> Hmm.... the addition of "--framework Foundation" should prevent this
> and ensure that the Obj-C runtime is initialised. Can you confirm that
> your compile includes this flag? (it should be added automatically for
> the darwin platform by the appropriate section in extconf.rb

The full result of typing 'make' is (sorry for the long ugly post):

Now Making glut extend module
gcc -fno-common -g -O2  -fno-common -pipe -fno-common -I.
-I/System/Library/Frameworks/OpenGL.framework/Headers
-I/System/Library/Frameworks/GLUT.framework/Headers  -I.
-I/usr/lib/ruby/1.8/powerpc-darwin7.9.0
-I/usr/lib/ruby/1.8/powerpc-darwin7.9.0 -I.   -c glut.c
glut.c: In function `glut_KeyboardFunc':
glut.c:157: warning: passing arg 1 of `glutKeyboardFunc' from
incompatible pointer type
cc -dynamic -bundle -undefined suppress -flat_namespace -framework
OpenGL -framework GLUT -framework Foundation  -L"/usr/lib"
-L"/System/Library/Frameworks/OpenGL.framework/Libraries/" -o
glut.bundle glut.o  -lruby -lGLU -lGL  -lpthread -ldl -lobjc   -lruby
Now Making opengl extend module
gcc -fno-common -g -O2  -fno-common -pipe -fno-common -I.
-I/System/Library/Frameworks/OpenGL.framework/Headers
-I/System/Library/Frameworks/GLUT.framework/Headers  -I.
-I/usr/lib/ruby/1.8/powerpc-darwin7.9.0
-I/usr/lib/ruby/1.8/powerpc-darwin7.9.0 -I.   -c glu.c
glu.c: In function `glu_PickMatrix':
glu.c:1185: warning: passing arg 2 of `ary2cint' from incompatible pointer type
glu.c: In function `glu_Project':
glu.c:1224: warning: passing arg 2 of `ary2cint' from incompatible pointer type
glu.c: In function `glu_UnProject':
glu.c:1269: warning: passing arg 2 of `ary2cint' from incompatible pointer type
gcc -fno-common -g -O2  -fno-common -pipe -fno-common -I.
-I/System/Library/Frameworks/OpenGL.framework/Headers
-I/System/Library/Frameworks/GLUT.framework/Headers  -I.
-I/usr/lib/ruby/1.8/powerpc-darwin7.9.0
-I/usr/lib/ruby/1.8/powerpc-darwin7.9.0 -I.   -c ogl.c
gcc -fno-common -g -O2  -fno-common -pipe -fno-common -I.
-I/System/Library/Frameworks/OpenGL.framework/Headers
-I/System/Library/Frameworks/GLUT.framework/Headers  -I.
-I/usr/lib/ruby/1.8/powerpc-darwin7.9.0
-I/usr/lib/ruby/1.8/powerpc-darwin7.9.0 -I.   -c rbogl.c
cc -dynamic -bundle -undefined suppress -flat_namespace -framework
OpenGL -framework GLUT -framework Foundation  -L"/usr/lib"
-L"/System/Library/Frameworks/OpenGL.framework/Libraries/" -o
opengl.bundle glu.o ogl.o rbogl.o  -lruby -lGLU -lGL  -lpthread -ldl
-lobjc   -lruby



So, it looks like I'm using the foundation framework.  Does ruby need
to be compiled with it also?