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Document behavior of Verilog system tasks

See original GitHub issue

Cocotb registers its own functions for Verilog system tasks:

$info
$warning
$error
$fatal

Document behavior of these system tasks:

Calls gpi_log with message
$fatal fails the current test

Issue Analytics

State:
Created 3 years ago
Comments:7 (6 by maintainers)

Top GitHub Comments

1reaction

ktbarrettcommented, Oct 8, 2020

@umarcor You may be interested in #2094 specifically.

1reaction

ktbarrettcommented, Oct 1, 2020

@gtaylormb Yeah, attempting to overload $fatal was a bad idea. Most simulators explicitly state you can’t overload builtin system tasks, which is why Questa isn’t happy. I think the idea behind $error not failing tests was that those commands were meant only for logging purposes. $error logs with the Python logger at the error level. Calling cocotb.log.error in Python does not cause a test failure, so it shouldn’t from HDL either. Personally, I think these logging system tasks are useless…

We do need system tasks to inform the cocotb regression manager of test failure or passage to better support cocotb as a general purpose cosimulation framework. @eine and @umarcor are also interested in this.

If you are interested in working on this, I’d be happy to assist.

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