Verilator errors (ex: lint errors when verilating) are suppressed when they should be displayed

[paul-demo]

This is my first time using cocotb-test and I'm using it with Verilator. I have used Verilator fairly extensively with just C++ testbenches. I'm following some alexforencich examples for cocotb-test which are basically this:

cocotb_unit_test.py:

import os
import deps
import cocotb_test.simulator

def register(top, file, parameters=None):
    def _register():
        cocotb_test.simulator.run(
            toplevel=top,
            module=os.path.splitext(os.path.basename(file))[0],
            verilog_sources=deps.get_dependencies(top + '.f'),
            parameters=parameters,
            compile_args=['-CFLAGS', '-Wno-deprecated',],
            timescale='1ns/1ps',
            waves=None,
        )
    return _register

syncfifo_test.py:

import cocotb
import cocotb.triggers
import cocotb_unit_test

@cocotb.test()
async def syncfifo_basic(dut):
    # TODO: testbench goes here

test_dut = cocotb_unit_test.register(top="syncfifo", file=__file__)

A makefile invokes the pytest file like this:

PYTHONPATH={blah} SIM=verilator WAVES=1 pytest -o log_cli=True

While this works fine for functional RTL, I found that if you have an RTL bug that the verilator linter would normally catch for you (like a misnamed variable), cocotb-test is suppressing the Verilator output that results from the "perl verilator ..." call, so all you get is the cryptic message: "SystemExit: Process .../verilator terminated with error 1". In reality the verilator command that failed prints a ton of useful debugging information before returning that value of 1, and it seems the cocotb-test should be displaying it.