{"ast_node_type":"other","tokens":[{"end":45,"kind":"keyword","start":0,"text":"*CURRENT_OVERRIDABLE.get_or_init(||"}]}
        *CURRENT_OVERRIDABLE.get_or_init(|| {
    pub fn current_overridable() -> Self {
            if let Ok(override_var) = std::env::var("RUSTC_OVERRIDE_VERSION_STRING")