WARNING: [Synth 8-3936] Found unconnected internal register 'nxt_credit_reg' and it is trimmed from '16' to '15' bits. [/data/home/no56hud/synthesis-vcu108/build/optimsoc_examples_compute_tile_vcu108/src/glip_common_credit/verilog/debtor.v:58]
That should be harmless, however it would be nice to get rid of this warning.