dmd Detect undocumented command-line options

Works when dmd is compiled in debug mode. Only detects simple non-suffix options.

Hopefully any PRs forgetting to call gotOpt will be detected in reviews as surrounding lines tend to call it. Failing that, at least we can grep for if (arg == " to list all the hidden/unchecked options (e.g. -quiet, --b).

Add docs for -multiobj, -nofloat, -vcg-ast.

Nov 08 '22 14:11 ntrel

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	23471	enhancement	undocumented dmd CLI options

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub run digger -- build "master + dmd#14630"

Nov 08 '22 14:11 dlang-bot

What's the issue ? We already detect unused arguments L2550 / 2580:

        else
        {
        Lerror:
            error("unrecognized switch '%s'", arguments[i]);
            continue;
        Lnoarg:
            error("argument expected for switch '%s'", arguments[i]);
            continue;
        }

Nov 08 '22 15:11 Geod24

@Geod24 This helps detect valid options that don't have --help documentation.

Nov 08 '22 15:11 ntrel

You can see the check firing in the tests for the first commit (before I added missing docs) here: https://app.circleci.com/pipelines/github/dlang/dmd/23098/workflows/1da53291-0849-49a4-b6c1-6bc0f758fa21/jobs/50668

core.exception.AssertError@src/dmd/mars.d(1596): missing doc for -multiobj in cli.d

Nov 08 '22 15:11 ntrel

Add docs for -multiobj, -nofloat, -vcg-ast.

Note sure about the first two, but -vcg-ast was intentionally not documented because it was meant for internal use.

Nov 08 '22 15:11 dkorpel

I suggest adding a parameter to gotOpt so you can specify that a switch is deliberately undocumented, and add documentation to switches in a separate PR.

Nov 08 '22 16:11 dkorpel

Thanks for cleaning up the argument parsing code!