Quartus appears to have had a crush

Engineering found that the root cause of the error is that Quartus standard incorrectly processes the escaped names of the type

reg [7:0] \cfblk203_reg[0] ;

This is in the file Subsystem_yosys.v

I see that the file is generated bythe yosys tool. yosys may have an option to generate the names differently.

For example, if we change the name to

reg [7:0] clkbuf203_reg_0;

This will be handled properly by Quartus standard.

Regards,

Richard Tan