ports tree broken with cycling dependencies

[Andriy Gapon]

It seems that after todays portsnap (1 hour ago) my port tree is broken
by having cycling dependencies.
Example:
/usr/ports/graphics/cairo$ make all-depends-list | grep pango
/usr/ports/x11-toolkits/pango
/usr/ports/x11-toolkits/pango$ make all-depends-list | grep cairo
/usr/ports/graphics/cairo

I think the root cause is that x11/xorg-libraries port has (run)
dependency on x11/pixman port which has a (auto-detected) dependency
USE_GNOME+=gtk20 where gtk20 port, of course, has a dependency on
xorg-libraries.

-- 
Andriy Gapon