}

    private DirectoryContents toDir(File includeDir) {
        DirectoryContents directoryContents = includeRoots.get(includeDir);
        if (directoryContents == null) {
            directoryContents = new DirectoryContents(includeDir);
            includeRoots.put(includeDir, directoryContents);
        }
        return directoryContents;
    }

    private static boolean containsFiles(File directory) {
        if (!directory.exists() || !directory.isDirectory()) {
            return false;
        }
        try (Stream<Path> directoryContents = Files.walk(directory.toPath())) {
            return directoryContents.anyMatch(Files::isRegularFile);
        } catch (IOException e) {
            throw UncheckedException.throwAsUncheckedException(e);
        }
    }

Class <org.gradle.language.nativeplatform.internal.incremental.DefaultSourceIncludesResolver$DirectoryContents> is not annotated (directly or via its package) with @org.gradle.api.NonNullApi in (DefaultSourceIncludesResolver.java:0)