Signal name a[0:0]

[regymm]

When a top-level signal is named a[0:0], and in constraint file something like set_property PACKAGE_PIN D11 [get_ports {pci_exp_rxp[0]}] is used, the I/O pin can't be processed by nextpnr-xilinx correctly. Nextpnr reports Error 134.

This may be a low-priority issue.