C++ const doesn't actually provide constness for purposes of concurrent access unless you follow a bunch of other rules (no const_cast, no use of "mutable", no

C++ const doesn't actually provide constness for purposes of concurrent access unless you follow a bunch of other rules (no const_cast, no use of "mutable", no use of mutable class statics, no use of mutable file-level statics, no use of mutable globals) that in practice people violate all the time even with const objects.