NationalSecurityAgency/ghidra · warning · IllegalArgumentException

Unexpected argument: {}

Error message

Unexpected argument: {}

What it means

Thrown when a positional (non-option) argument appears after -- long-form options have already been encountered. BSim's argument parser tracks a sawOptions flag: once any -- option is seen, no further bare positional arguments are allowed. All positional arguments must come before all options.

Source

Thrown at Ghidra/Features/BSim/src/main/java/ghidra/features/bsim/query/ingest/BSimLaunchable.java:324

				int ix = optionName.indexOf("=");
				if (ix > 1) {
					value = optionName.substring(ix + 1);
					optionName = optionName.substring(0, ix);
				}
			}

			String option = optionName;

			if (optionName.startsWith("-") && !optionName.startsWith("--")) {
				option = SHORTCUT_OPTION_MAP.get(optionName); // map option to -- long form
				if (option == null) {
					throw new IllegalArgumentException("Unsupported option use: " + optionName);
				}
			}

			if (!option.startsWith("--")) {
				if (sawOptions) {
					throw new IllegalArgumentException("Unexpected argument: " + option);
				}
				subParams.add(params[i]);
				continue;
			}

			sawOptions = true;
			if (!GLOBAL_OPTIONS.contains(option) && !allowedParams.contains(option)) {
				throw new IllegalArgumentException("Unsupported option use: " + optionName);
			}
			if (!VALUE_OPTIONS.contains(option)) {
				// consume option without value arg as a boolean option
				if (value != null) {
					throw new IllegalArgumentException(
						"Unsupported option specification: " + optionName + "=");
				}
				booleanOptions.add(option);
			}
			else if (!StringUtils.isBlank(value)) {

View on GitHub (pinned to d5f144c24d)

Solutions

1. Reorder arguments so all positional parameters precede all -- options.
2. Remove any stray or unexpected tokens from the command line.
3. Quote arguments that might be expanded by the shell to prevent unexpected tokens.

Example fix

// before
bsim delete h2://localhost/db --md5 abc123 /path/to/extra
// error: Unexpected argument: /path/to/extra

// after
bsim delete h2://localhost/db /path/to/extra --md5 abc123

// Validate that no positional argument appears after the first -- option
boolean sawOption = false;
for (String arg : args) {
    if (arg.startsWith("--")) {
        sawOption = true;
    } else if (!arg.startsWith("-") && sawOption) {
        throw new IllegalArgumentException("Positional argument '" + arg + "' appears after options");
    }
}

When it happens

Trigger: A command like 'bsim listexes h2://localhost/db --limit 10 extra_pos' where 'extra_pos' appears after --limit. The parser treats anything not starting with - as a positional argument and rejects it after options.

Common situations: Placing a file path or repository name after options instead of before them; accidentally including a stray token after the last option; shell glob expansion producing an unexpected token.

Related errors

• Unsupported option use: {}
• Unsupported option specification: {}=
• Missing option value: {}
• Missing required parameter: {}
• Missing required parameter ({}) before specified option: {}

AI-assisted analysis of NationalSecurityAgency/ghidra@d5f144c24d (2026-08-14). Data as JSON: /api/errors/e1246d33d15ad09c. Report an issue: GitHub.