//! Type definitions for learning about the dependency formats of all upstream
//! crates (rlibs/dylibs/oh my).
//!
//! For all the gory details, see the provider of the `dependency_formats`
//! query.

// FIXME: move this file to rustc_metadata::dependency_format, but
// this will introduce circular dependency between rustc_metadata and rustc_middle

use rustc_macros::{Decodable, Encodable, HashStable};
use rustc_session::config::CrateType;

/// A list of dependencies for a certain crate type.
///
/// The length of this vector is the same as the number of external crates used.
pub type DependencyList = Vec<Linkage>;

/// A mapping of all required dependencies for a particular flavor of output.
///
/// This is local to the tcx, and is generally relevant to one session.
pub type Dependencies = Vec<(CrateType, DependencyList)>;

#[derive(Copy, Clone, PartialEq, Debug, HashStable, Encodable, Decodable)]
pub enum Linkage {
    NotLinked,
    IncludedFromDylib,
    Static,
    Dynamic,
}