I have Redhat 7.1 linux. When I tried to compile the double.c from OpenGL Programming Guide(red book) with gcc, it always gave me an error message such as "…libGL.so undefined reference to ‘pow’. The command I used was gcc -L/usr/X11R6/lib -lGL -lGLU -lglut double.c. The double.c does not invoke ‘pow’ by itself. After a while, I used g++ to compile with same libs, and it worked fine. Did anybody have same problem with gcc?