Cargo Features

[dependencies]
memcache = { version = "0.17.2", default-features = false, features = ["tls"] }
default = tls

The tls feature is set by default whenever memcache is added without default-features = false somewhere in the dependency tree.

tls default = openssl

Features from optional dependencies

In crates that don't use the dep: syntax, optional dependencies automatically become Cargo features. These features may have been created by mistake, and this functionality may be removed in the future.

openssl tls