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# Error code E0711

#### This error code is internal to the compiler and will not be emitted with normal Rust code.

Feature declared with conflicting stability requirements.

    #![allow(unused)]
    fn main() {
    // NOTE: this attribute is perma-unstable and should *never* be used outside of
    //       stdlib and the compiler.
    #![feature(staged_api)]

    #![stable(feature = "...", since = "1.0.0")]

    #[stable(feature = "foo", since = "1.0.0")]
    fn foo_stable_1_0_0() {}

    // error: feature `foo` is declared stable since 1.29.0
    #[stable(feature = "foo", since = "1.29.0")]
    fn foo_stable_1_29_0() {}

    // error: feature `foo` is declared unstable
    #[unstable(feature = "foo", issue = "none")]
    fn foo_unstable() {}
    }

In the above example, the `foo` feature is first defined to be stable since 1.0.0, but is then re-declared stable since 1.29.0. This discrepancy in versions causes an error. Furthermore, `foo` is then re-declared as unstable, again the conflict causes an error.

This error can be fixed by splitting the feature, this allows any stability requirements and removes any possibility of conflict.