Clock uncertainty warnings under 10.0

[Altera_Forum]

I have a project that works fine under 9.0 - no timing violations. I upgraded to 10.0 and rebuilt without any warnings. If I now go into TimeQuest and perform a derive_clock_uncertainty followed by an update_timing_netlist, and then write out the .sdc, the new .sdc appears to be incomplete. When I build with the new .sdc, Quartus issues critical warnings that no clock uncertainty assignments exist for several of the signals. A search of the .sdc shows the signals in question don't have set_clock_uncertainty for the path in question, although the .sdc does have uncertainties for many of the paths and has all of the expected sections. Is there an additional step that's now needed? I've tried using the -overwrite option on the derive_clock_uncertainty but (as expected) that doesn't change if an uncertainty assignment gets created.

[Altera_Forum]

How come there are ad links in your post? (Wondering if you did that or there is some new way to spam)? 

I recommend against writing out an .sdc and using that. Treat the .sdc like HDL that you write, i.e. if Quartus could write out a machine-generated version of the same thing, you wouldn't want to overwrite your stuff. If anything, write_sdc to a junk file and then copy over the commands you want. As for uncertainty, just have "derive_clock_uncertainty" in your .sdc instead of individual set_clock_uncertainty commands. It will always pick up all the clocks and you don't have to worry about it.

[Altera_Forum]

Hmm, it looks like the spammers are getting tricky(er). This is a verbatim copy of michael.d.miller (http://alteraforum.org/forum/member.php?u=10812)'s 2010/09/22 question with the spam links added. (Why would we be interested in shoes here!) Anyway, agree with your answer :-)

[Altera_Forum]

Ugh. Now just having a good question doesn't necessarily mean it's not spam. How many people can really be buying Dolce & Gabbana shoes from the Altera forum?

[Altera_Forum]

It depends... are those shoes compatible with the USB Blaster? I can't find the Jtag connector pinout

[Altera_Forum]

Nice one. :)