Debian AMD64, fglrx
Broken: current git
Short description of error
The new "Clip" option for image extrapolation on the Image Texture Node does not clip UVs that are >1.0, which is not correct. (Alpha should be 0.0 here)
On the other hand it does UV clipping for UVs <0.0, which is correct.
If you need an example .blend please tell me, but probably this should be trivial to fix.