createClkTreeSpec not generating ctstch file with roots

Hi All,

I am trying to read in the constraints which contain create clock commands,and then try the createClkTreeSpec command with alist of usable buffers and inverters.

However it does dump out a file with exclude points, dont touch nets etc., but doenst dump out the clock tree root pins definitions.

Can some one point me what I might be doing wrong.

Thanks,

Rajesh.