some features not found in Cargo.toml

[cssivision]

all features rustc-serialize serde v1 v3 v4 v5 use_std, but only v1 v3 v4 v5 use_std in the Cargo.toml, lack of rustc-serialize serde(i am new to rust-lang, maybe this is a stupid question).

[alexcrichton]

Thanks for the report! This is due to the fact, however, that rustc-serialize and serde are optional dependencies, which implicitly makes them a feature.