gamma warnings bug

["K. Richard Pixley" <rich kyoto noir com>]

On my system, (originally redhat-5.0), the usage of "gamma" to declare
function arguments collides with /usr/include/mathcalls.h producing...

gcc -DHAVE_CONFIG_H -I. -I. -I. -I/usr/local/include -I/usr/lib/glib/include -I/usr/X11R6/include -g -Wall -Wshadow -Wmissing-prototypes -Wstrict-prototypes -Winline -Wpointer-arith -O6 -pipe -fstrength-reduce -fexpensive-optimizations -finline-functions -frerun-cse-after-loop -freg-struct-return -fnonnull-objects -c -fPIC -DPIC glemisc.c
In file included from /usr/include/gtk/gtkcolorsel.h:30,
                 from /usr/include/gtk/gtk.h:36,
                 from glemisc.h:22,
                 from glemisc.c:20:
/usr/include/gtk/gtkpreview.h:128: warning: declaration of `gamma' shadows global declaration

I think those arguments should be renamed.

--rich