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AR# 11950

11.1 NGDBuild - "ERROR:NgdBuild:19- Errors found while parsing constraint file '.ucf'."


When trying to lock signals or instances that are not in the design, NGDBuild (Translate) reports the following errors:

"ERROR:Parsers:11 - Encountered unrecognized constraint while parsing."

"ERROR:NGDBuild:19 - Errors found while parsing constraint file '<design>.ucf."


This error will occur if a constraint is applied to a net or instance that does not exist in the design. There are two ways to avoid this error:

1. Remove the offending constraint from the UCF file.

2. Select the "-aul" (Allow Unmatched LOC Constraints) switch in Translate (NGDBuild). Any unmatched LOC constraints will be ignored during implementation.

AR# 11950
Date Created 08/29/2007
Last Updated 12/15/2012
Status Active
Type General Article