Cargo Features

compiletest_rs has no features set by default.

[dependencies]
compiletest_rs = { version = "0.11.1", features = ["tmp", "rustc", "stable"] }
tmp = tempfile
rustc
stable

Does nothing. Should be removed at next major release

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.

tempfile tmp?