Cargo Features

hmc5883-async has no features set by default.

[dependencies]
hmc5883-async = { version = "0.1.3", features = ["rttdebug"] }
rttdebug = panic-rtt-core

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.

panic-rtt-core rttdebug?

Enables panic-rtt-core ^0.1.0