When loading a sharable object, version definition data from the loaded object is analyzed to assure that it meets the version requirements of the calling object. The dynamic loader retrieves the entries in the caller's Elfxx_Verneed array and attempts to find matching definition information in the loaded Elfxx_Verdef table.
Each object and dependency is tested in turn. If a symbol definition is missing, the loader returns an error. A warning is issued instead of a hard error when the vna_flags bit for VER_FLG_WEAK is set in the Elfxx_Vernaux entry.
When the versions referenced by undefined symbols in the loaded object are found, version availability is certified. The test completes without error and the object is made available.