uninitialized provides std::mem::uninitialized() behaviour only when a project is willing to take the risk of uninitialized data being passed to external interfaces. By default it is equivalent to std::mem::zeroed().

The feature uninitialized may be turned on to revert to the unsafe behaviour. Optionally, the UNSAFE_UNINITIALIZED=1 environment variable may be set at build time.

See the documentation for up to date information.