General Description: The following error is reported:
"ERROR:Pack:679 - Unable to obey design constraints."
When NGDBuild flattens a hierarchical EDIF file containing SRL16s with XBLKNM properties that were created by Leonardo Spectrum, NGDBuild does not do anything to the XBLKNM properties in the EDIF file (such as adding an instance label to the value). The placer will then try to put more SRL16s into a single slice than is physically possible, and the error above is reported.
One way to work around this problem is to not preserve the hierarchy in Leonardo Spectrum.
The following Leonardo Level 3 TCL script will ensure that the XBLKNM is stripped from the EDIF file. Run this script after optimization, but before writing out the EDIF file: