[BUG] `$fatal` call in `cve2_top_tracing.sv` not following latest SystemVerilog IEEE standard (1800-2012)

[ozografos]

Bug Description

cve2/rtl/cve2_top_tracing.sv

Line 87 in b72358c

$fatal("Fatal error: RVFI needs to be defined globally.");

It seems that this $fatal call has a syntax error when trying to run with industrial EDA. If I understand correctly the correct syntax would be:

$fatal(1, "Message")

[MikeOpenHWGroup]

Good catch @ozografos. It seems that most (all?) simulators will handle $fatal("Msg"); in a non-standard way. For example, DSim will end the simulation without printing the message. You are correct that a fatal_number should be the first argument (either 0, 1 or 2). I would recommend "1".

If you were to create a pull-request to resolve this, that would be appreciated. Please review CONTRIBUTING first.

[ozografos]

Would it be the safest approach to change $fatal calls to:

$display("Fatal error: <message>");
$fatal(1);

[MikeOpenHWGroup]

Why is this a safer approach?

[ozografos]

Why is this a safer approach?

Safer in the sense of avoiding non-standard ways of handling $fatal. $display("msg") should always print a message and $fatal(1) will always exit the simulation, regardless of simulator. Haven't not tested this though, so I may be wrong.

[MikeOpenHWGroup]

$fatal(fatal_number, "msg"); has been part of IEEE-1800 since 2003, so your initial suggestion should work with all simulators.