Rollup merge of #41141 - michaelwoerister:direct-metadata-ich-final, r=nikomatsakis

[rust.git] / src / librustc / ty / mod.rs

diff --git a/src/librustc/ty/mod.rs b/src/librustc/ty/mod.rs
index 292e30e3d41f19403353bfdd2a055ac4c1066daf..23f35d3bdd7929e262e1a56313ed7edf88dfe48d 100644 (file)
--- a/src/librustc/ty/mod.rs
+++ b/src/librustc/ty/mod.rs
@@ -452,6 +452,23 @@ fn hash<H: Hasher>(&self, s: &mut H) {
     }
 }
 
+impl<'a, 'tcx> HashStable<StableHashingContext<'a, 'tcx>> for ty::TyS<'tcx> {
+    fn hash_stable<W: StableHasherResult>(&self,
+                                          hcx: &mut StableHashingContext<'a, 'tcx>,
+                                          hasher: &mut StableHasher<W>) {
+        let ty::TyS {
+            ref sty,
+
+            // The other fields just provide fast access to information that is
+            // also contained in `sty`, so no need to hash them.
+            flags: _,
+            region_depth: _,
+        } = *self;
+
+        sty.hash_stable(hcx, hasher);
+    }
+}
+
 pub type Ty<'tcx> = &'tcx TyS<'tcx>;
 
 impl<'tcx> serialize::UseSpecializedEncodable for Ty<'tcx> {}
@@ -1411,13 +1428,16 @@ pub struct ReprOptions {
     pub packed: bool,
     pub simd: bool,
     pub int: Option<attr::IntType>,
+    // Internal only for now. If true, don't reorder fields.
+    pub linear: bool,
 }
 
 impl_stable_hash_for!(struct ReprOptions {
     c,
     packed,
     simd,
-    int
+    int,
+    linear
 });
 
 impl ReprOptions {
@@ -1440,6 +1460,9 @@ pub fn new(tcx: TyCtxt, did: DefId) -> ReprOptions {
             ret.simd = true;
         }
 
+        // This is here instead of layout because the choice must make it into metadata.
+        ret.linear = !tcx.consider_optimizing(|| format!("Reorder fields of {:?}",
+            tcx.item_path_str(did)));
         ret
     }