ID:13684 VHDL error at <location>: attribute "<name>" cannot be used in constraint

CAUSE: In a VHDL Design File (.vhd) at the specified location, you used the specified attribute in a constraint. However, the attribute cannot be used in constraints. Only certain attributes such as 'BASE, 'RANGE, and 'REVERSE_RANGE can be used to return constraints from a name.

ACTION: Remove the attribute from the constraint.