Changes to vpi/sys_display.c
Changes to vpi/sys_display.c

First and second areas were changed for "Microsoft Visual Studio Express 2015 RC Web" so that gold files would match.  For the third area of change, "Microsoft Visual Studio Express 2015 RC Web" wanted to print 6 zeros after the decimals for the values of 0.0 and -0.0, and then the gold files wouldn't match.

themperek/iverilog,CastMi/iverilog,CastMi/iverilog,themperek/iverilog,themperek/iverilog,CastMi/iverilog