Proper dependencies for "x11"

[Mojca Miklavec]

Hi,

When exploring different aspects of x11 I realised that gnuplot uses
    depends_lib-append port:xpm
for x11 variant, but links to the following libraries (among others):

/opt/local/lib/libXpm.4.dylib
/opt/local/lib/libX11.6.dylib
/opt/local/lib/libgtk-x11-2.0.0.dylib
/opt/local/lib/libgdk-x11-2.0.0.dylib
/opt/local/lib/libgio-2.0.0.dylib
/opt/local/lib/libXrender.1.dylib
/opt/local/lib/libXinerama.1.dylib
/opt/local/lib/libXi.6.dylib
/opt/local/lib/libXrandr.2.dylib
/opt/local/lib/libXcursor.1.dylib
/opt/local/lib/libXcomposite.1.dylib
/opt/local/lib/libXdamage.1.dylib
/opt/local/lib/libXfixes.3.dylib
/opt/local/lib/libXext.6.dylib
/opt/local/lib/libatk-1.0.0.dylib
/opt/local/lib/libgdk_pixbuf-2.0.0.dylib

What is the proper way to declare the dependencies? Is dependence on
xpm alone enough?

I also notices linking to tiff, freetype, glib2, gettext without
declaring an explicit dependence, but some of those are dependencies
of gd2, for some I didn't check.

Mojca