What causes "{e} (required by {self.name})" in oracle/graal?

Read the inner message: 'Unknown component: X (required by Y)' tells you the bad name X and the component Y that declares it; fix Y's dependency_names in its suite.py.

oracle/graal · error · RuntimeError

{e} (required by {self.name})

Error message

{e} (required by {self.name})

What it means

GraalVmComponent.direct_dependencies() resolves each name in dependency_names via graalvm_component_by_name(); any failure (typically 'Unknown component: X') is re-raised as RuntimeError with the dependent component's name appended, so you know which suite component had the bad dependency.

Source

Thrown at sdk/mx.sdk/mx_sdk_vm.py:389

        assert isinstance(self.support_distributions, list)
        assert isinstance(self.support_headers_distributions, list)
        assert isinstance(self.support_libraries_distributions, list)
        assert isinstance(self.license_files, list)
        assert isinstance(self.third_party_license_files, list)
        assert isinstance(self.provided_executables, list)
        assert isinstance(self.boot_jars, list)
        assert isinstance(self.jvmci_parent_jars, list)
        assert isinstance(self.launcher_configs, list)
        assert isinstance(self.library_configs, list)

    def __str__(self):
        return f"{self.name} ({self.dir_name})"

    def direct_dependencies(self):
        try:
            return [graalvm_component_by_name(name) for name in self.dependency_names]
        except Exception as e:
            raise RuntimeError(f"{e} (required by {self.name})") from e


class GraalVmTruffleComponent(GraalVmComponent):
    def __init__(self, suite, name, short_name, license_files, third_party_license_files, truffle_jars,
                 include_in_polyglot=None, standalone_dir_name=None, standalone_dir_name_enterprise=None,
                 standalone_dependencies=None, standalone_dependencies_enterprise=None, **kwargs):
        """
        :param list[str] truffle_jars: JAR distributions that should be on the classpath for the language implementation.
        :param bool include_in_polyglot: whether this component is included in `--language:all` or `--tool:all` and should be part of polyglot images (deprecated).
        :param str standalone_dir_name: name for the standalone archive and directory inside
        :param str standalone_dir_name_enterprise: like `standalone_dir_name`, but for the EE standalone. Defaults to `standalone_dir_name` if not set.
        :param dict[str, (str, list[str])] standalone_dependencies: dict of dependent components to include in the CE standalone in the form {component name: (relative path, excluded_paths)}.
        :param dict[str, (str, list[str])] standalone_dependencies_enterprise: like `standalone_dependencies`, but for the EE standalone. Defaults to `standalone_dependencies` if not set.
        """
        super().__init__(suite, name, short_name, license_files, third_party_license_files,
                                                      jar_distributions=truffle_jars, **kwargs)
        if include_in_polyglot is not None:
            mx.warn('"include_in_polyglot" is deprecated. Please drop all uses.')

View on GitHub (pinned to a66e9ccd1d)

Solutions

Read the inner message: 'Unknown component: X (required by Y)' tells you the bad name X and the component Y that declares it; fix Y's dependency_names in its suite.py.
If X should exist, make sure the suite defining it is included in the mx run (not excluded by -p/--suite restrictions).
For removed components, update or remove dependents rather than papering over the error.

Example fix

# before (suite.py of component Y)
deps=['graalvm-llvmlanguage']   # component renamed -> RuntimeError

# after (suite.py of component Y)
deps=['graalvm-llvm']

Defensive patterns

Strategy: try-catch

Validate before calling

for dep in component.dependency_names:
    if graalvm_component_by_name(dep, fatalIfMissing=False) is None:
        raise SystemExit(f"{component.name} depends on unknown component '{dep}'; fix suite.py")

Try / catch

try:
    deps = component.direct_dependencies()
except RuntimeError as e:
    # message is '<inner error> (required by <component>)':
    # fix the named component's dependency_names, then retry
    raise

Prevention

After renaming or removing a GraalVM component, grep all suite.py files for its old name.
Run a dependency-name lint (resolve every dep with fatalIfMissing=False) as part of CI.
Avoid restricting suites (-p) in builds whose components have cross-suite deps.

When it happens

Trigger: A component's suite.py 'deps' entry names a component that is not registered (typo, not-yet-loaded suite, or removed component) and dependency resolution runs during image layout.

Common situations: Renaming/removing a GraalVM component without updating dependents; running with a subset of suites (specific_suites) that excludes the suite defining the dependency; typos in dependency names.

Related errors

AI-assisted analysis of oracle/graal@a66e9ccd1d (2026-08-14). Data as JSON: /api/errors/64fb658c994109b8. Report an issue: GitHub.