Users may see a warning similar to the following on Xilinx library macros that utilize the INC-FG-CI carry logic mode (CC8CE, CC8CLE, CC16CLE, etc.):
WARNING:x4kma - Signal `Q15_OUT' on pin G4 of CY4 symbol `$1I17/$1I141' (output signal=$1I17/C14) is not required by carry mode INC-F-CI. The signal is being removed.
This is a known problem with the M1.3 design entry libraries. The warning is valid, and the trimming of the extraneous signal should not be cause for concern.
MAP is simply optimizing the INC-FG-CI mode carry logic into INC-F-CI and removing unecessary signals.
The warning may not be meaningful at first glance because the optimization from INC-FG-CI to INC-F-CI that occurs before the signals are actually trimmed is reported in a separate section of the Map .MRP report. However, the trimming is valid.