TestUtil.supportsLinks checks whether a symbolic link can be created in a given directory. A couple of tests use its result in the case of creating a hard link. Given that file systems exist which support symbolic links but not hard links, this can lead to erroneous results. This is the case for example for a FAT32 file system mounted on a macOS host. This problem was discovered by running java/nio/file/Files/CheckPermissions.java with the temporary directory set to the default and the work directory on an external FAT32 file system.