Built-in implementation of Tuple trait

[rust.git] / compiler / rustc_middle / src / traits / mod.rs

diff --git a/compiler/rustc_middle/src/traits/mod.rs b/compiler/rustc_middle/src/traits/mod.rs
index 72b848c3ee2dd150728d09ba9a05e1d556597b2a..53d22eb00706d93c05030654dc9ffcdb7b32a4c2 100644 (file)
--- a/compiler/rustc_middle/src/traits/mod.rs
+++ b/compiler/rustc_middle/src/traits/mod.rs
@@ -634,6 +634,10 @@ pub enum ImplSource<'tcx, N> {
 
     /// ImplSource for a `const Drop` implementation.
     ConstDestruct(ImplSourceConstDestructData<N>),
+
+    /// ImplSource for a `std::marker::Tuple` implementation.
+    /// This has no nested predicates ever, so no data.
+    Tuple,
 }
 
 impl<'tcx, N> ImplSource<'tcx, N> {
@@ -648,7 +652,8 @@ pub fn nested_obligations(self) -> Vec<N> {
             ImplSource::Object(d) => d.nested,
             ImplSource::FnPointer(d) => d.nested,
             ImplSource::DiscriminantKind(ImplSourceDiscriminantKindData)
-            | ImplSource::Pointee(ImplSourcePointeeData) => Vec::new(),
+            | ImplSource::Pointee(ImplSourcePointeeData)
+            | ImplSource::Tuple => Vec::new(),
             ImplSource::TraitAlias(d) => d.nested,
             ImplSource::TraitUpcasting(d) => d.nested,
             ImplSource::ConstDestruct(i) => i.nested,
@@ -666,7 +671,8 @@ pub fn borrow_nested_obligations(&self) -> &[N] {
             ImplSource::Object(d) => &d.nested,
             ImplSource::FnPointer(d) => &d.nested,
             ImplSource::DiscriminantKind(ImplSourceDiscriminantKindData)
-            | ImplSource::Pointee(ImplSourcePointeeData) => &[],
+            | ImplSource::Pointee(ImplSourcePointeeData)
+            | ImplSource::Tuple => &[],
             ImplSource::TraitAlias(d) => &d.nested,
             ImplSource::TraitUpcasting(d) => &d.nested,
             ImplSource::ConstDestruct(i) => &i.nested,
@@ -733,6 +739,7 @@ pub fn map<M, F>(self, f: F) -> ImplSource<'tcx, M>
                     nested: i.nested.into_iter().map(f).collect(),
                 })
             }
+            ImplSource::Tuple => ImplSource::Tuple,
         }
     }
 }