
$(COGL_DRIVER)/cogl-defines.h is generated in the configure script so it ends up in the build directory. Therefore the build rule for cogl/cogl-defines.h should depend on the file in $(builddir) not $(srcdir).
$(COGL_DRIVER)/cogl-defines.h is generated in the configure script so it ends up in the build directory. Therefore the build rule for cogl/cogl-defines.h should depend on the file in $(builddir) not $(srcdir).