Ben,
A fresh version of XEmacs, configured with:
../xemacs-21.5/configure --prefix=/usr/local/gcc3-world --with-gnome
produces:
make[1]: *** No rule to make target `events-mod.h', needed by `event-gtk.o'.
Stop.
make[1]: Leaving directory `/home/malcolmp/devl/xemacs/objdir/src'
make: *** [src] Error 2
System: PPC linux, GCC 3.0.4.
Malcolm