Why is the output of my Constant Coefficient Multiplier (CCM), with a constant value of (2^64)-1, incorrect?
This is fixed in Multiplier Generator v10.0.
The way to work around this issue is to use the "direct instantiation" method described in the core data sheet to instantiate the core directly in VHDL code. The constant can be supplied as a binary string in this case which will be passed correctly for synthesis.
The direct instantiation method is also documented in the COREGen User Guide.