Cargo Features

[dependencies]
MacTypes-sys = { version = "2.1.0", default-features = false, features = ["use_std"] }
default = use_std

The use_std feature is set by default whenever MacTypes-sys is added without default-features = false somewhere in the dependency tree.

use_std default

Enables use_std of libc

libc:

use_std is deprecated, use std instead

MacTypes-sys has 2 features without comments.