Mark derived StructuralEq as automatically derived.

compiler/rustc_builtin_macros/src/deriving/mod.rs

@@ -131,23 +131,27 @@ fn inject_impl_of_structural_trait(
     // Create generics param list for where clauses and impl headers
     let mut generics = generics.clone();
 
+    let ctxt = span.ctxt();
+
     // Create the type of `self`.
     //
     // in addition, remove defaults from generic params (impls cannot have them).
     let self_params: Vec<_> = generics
         .params
         .iter_mut()
         .map(|param| match &mut param.kind {
-            ast::GenericParamKind::Lifetime => {
-                ast::GenericArg::Lifetime(cx.lifetime(span, param.ident))
-            }
+            ast::GenericParamKind::Lifetime => ast::GenericArg::Lifetime(
+                cx.lifetime(param.ident.span.with_ctxt(ctxt), param.ident),
+            ),
             ast::GenericParamKind::Type { default } => {
                 *default = None;
-                ast::GenericArg::Type(cx.ty_ident(span, param.ident))
+                ast::GenericArg::Type(cx.ty_ident(param.ident.span.with_ctxt(ctxt), param.ident))
             }
             ast::GenericParamKind::Const { ty: _, kw_span: _, default } => {
                 *default = None;
-                ast::GenericArg::Const(cx.const_ident(span, param.ident))
+                ast::GenericArg::Const(
+                    cx.const_ident(param.ident.span.with_ctxt(ctxt), param.ident),
+                )
             }
         })
         .collect();
@@ -174,6 +178,8 @@ fn inject_impl_of_structural_trait(
             })
             .cloned(),
     );
+    // Mark as `automatically_derived` to avoid some silly lints.
+    attrs.push(cx.attribute(cx.meta_word(span, sym::automatically_derived)));
 
     let newitem = cx.item(
         span,

src/test/ui/deriving/deriving-all-codegen.stdout

@@ -46,13 +46,15 @@ impl ::core::default::Default for Empty {
 impl ::core::hash::Hash for Empty {
     fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {}
 }
-impl ::core::marker::StructuralPartialEq for Empty {}
+#[automatically_derived]
+impl ::core::marker::StructuralPartialEq for Empty { }
 #[automatically_derived]
 impl ::core::cmp::PartialEq for Empty {
     #[inline]
     fn eq(&self, other: &Empty) -> bool { true }
 }
-impl ::core::marker::StructuralEq for Empty {}
+#[automatically_derived]
+impl ::core::marker::StructuralEq for Empty { }
 #[automatically_derived]
 impl ::core::cmp::Eq for Empty {
     #[inline]
@@ -115,15 +117,17 @@ impl ::core::hash::Hash for Point {
         ::core::hash::Hash::hash(&self.y, state)
     }
 }
-impl ::core::marker::StructuralPartialEq for Point {}
+#[automatically_derived]
+impl ::core::marker::StructuralPartialEq for Point { }
 #[automatically_derived]
 impl ::core::cmp::PartialEq for Point {
     #[inline]
     fn eq(&self, other: &Point) -> bool {
         self.x == other.x && self.y == other.y
     }
 }
-impl ::core::marker::StructuralEq for Point {}
+#[automatically_derived]
+impl ::core::marker::StructuralEq for Point { }
 #[automatically_derived]
 impl ::core::cmp::Eq for Point {
     #[inline]
@@ -225,7 +229,8 @@ impl ::core::hash::Hash for Big {
         ::core::hash::Hash::hash(&self.b8, state)
     }
 }
-impl ::core::marker::StructuralPartialEq for Big {}
+#[automatically_derived]
+impl ::core::marker::StructuralPartialEq for Big { }
 #[automatically_derived]
 impl ::core::cmp::PartialEq for Big {
     #[inline]
@@ -236,7 +241,8 @@ impl ::core::cmp::PartialEq for Big {
             self.b8 == other.b8
     }
 }
-impl ::core::marker::StructuralEq for Big {}
+#[automatically_derived]
+impl ::core::marker::StructuralEq for Big { }
 #[automatically_derived]
 impl ::core::cmp::Eq for Big {
     #[inline]
@@ -345,13 +351,15 @@ impl ::core::hash::Hash for Unsized {
         ::core::hash::Hash::hash(&self.0, state)
     }
 }
-impl ::core::marker::StructuralPartialEq for Unsized {}
+#[automatically_derived]
+impl ::core::marker::StructuralPartialEq for Unsized { }
 #[automatically_derived]
 impl ::core::cmp::PartialEq for Unsized {
     #[inline]
     fn eq(&self, other: &Unsized) -> bool { self.0 == other.0 }
 }
-impl ::core::marker::StructuralEq for Unsized {}
+#[automatically_derived]
+impl ::core::marker::StructuralEq for Unsized { }
 #[automatically_derived]
 impl ::core::cmp::Eq for Unsized {
     #[inline]
@@ -410,13 +418,15 @@ impl ::core::hash::Hash for PackedCopy {
         ::core::hash::Hash::hash(&{ self.0 }, state)
     }
 }
-impl ::core::marker::StructuralPartialEq for PackedCopy {}
+#[automatically_derived]
+impl ::core::marker::StructuralPartialEq for PackedCopy { }
 #[automatically_derived]
 impl ::core::cmp::PartialEq for PackedCopy {
     #[inline]
     fn eq(&self, other: &PackedCopy) -> bool { { self.0 } == { other.0 } }
 }
-impl ::core::marker::StructuralEq for PackedCopy {}
+#[automatically_derived]
+impl ::core::marker::StructuralEq for PackedCopy { }
 #[automatically_derived]
 impl ::core::cmp::Eq for PackedCopy {
     #[inline]
@@ -479,7 +489,8 @@ impl ::core::hash::Hash for PackedNonCopy {
         ::core::hash::Hash::hash(__self_0_0, state)
     }
 }
-impl ::core::marker::StructuralPartialEq for PackedNonCopy {}
+#[automatically_derived]
+impl ::core::marker::StructuralPartialEq for PackedNonCopy { }
 #[automatically_derived]
 impl ::core::cmp::PartialEq for PackedNonCopy {
     #[inline]
@@ -489,7 +500,8 @@ impl ::core::cmp::PartialEq for PackedNonCopy {
         *__self_0_0 == *__self_1_0
     }
 }
-impl ::core::marker::StructuralEq for PackedNonCopy {}
+#[automatically_derived]
+impl ::core::marker::StructuralEq for PackedNonCopy { }
 #[automatically_derived]
 impl ::core::cmp::Eq for PackedNonCopy {
     #[inline]
@@ -540,15 +552,17 @@ impl ::core::hash::Hash for Enum0 {
         unsafe { ::core::intrinsics::unreachable() }
     }
 }
-impl ::core::marker::StructuralPartialEq for Enum0 {}
+#[automatically_derived]
+impl ::core::marker::StructuralPartialEq for Enum0 { }
 #[automatically_derived]
 impl ::core::cmp::PartialEq for Enum0 {
     #[inline]
     fn eq(&self, other: &Enum0) -> bool {
         unsafe { ::core::intrinsics::unreachable() }
     }
 }
-impl ::core::marker::StructuralEq for Enum0 {}
+#[automatically_derived]
+impl ::core::marker::StructuralEq for Enum0 { }
 #[automatically_derived]
 impl ::core::cmp::Eq for Enum0 {
     #[inline]
@@ -607,7 +621,8 @@ impl ::core::hash::Hash for Enum1 {
         }
     }
 }
-impl ::core::marker::StructuralPartialEq for Enum1 {}
+#[automatically_derived]
+impl ::core::marker::StructuralPartialEq for Enum1 { }
 #[automatically_derived]
 impl ::core::cmp::PartialEq for Enum1 {
     #[inline]
@@ -618,7 +633,8 @@ impl ::core::cmp::PartialEq for Enum1 {
         }
     }
 }
-impl ::core::marker::StructuralEq for Enum1 {}
+#[automatically_derived]
+impl ::core::marker::StructuralEq for Enum1 { }
 #[automatically_derived]
 impl ::core::cmp::Eq for Enum1 {
     #[inline]
@@ -676,13 +692,15 @@ impl ::core::default::Default for Fieldless1 {
 impl ::core::hash::Hash for Fieldless1 {
     fn hash<__H: ::core::hash::Hasher>(&self, state: &mut __H) -> () {}
 }
-impl ::core::marker::StructuralPartialEq for Fieldless1 {}
+#[automatically_derived]
+impl ::core::marker::StructuralPartialEq for Fieldless1 { }
 #[automatically_derived]
 impl ::core::cmp::PartialEq for Fieldless1 {
     #[inline]
     fn eq(&self, other: &Fieldless1) -> bool { true }
 }
-impl ::core::marker::StructuralEq for Fieldless1 {}
+#[automatically_derived]
+impl ::core::marker::StructuralEq for Fieldless1 { }
 #[automatically_derived]
 impl ::core::cmp::Eq for Fieldless1 {
     #[inline]
@@ -743,7 +761,8 @@ impl ::core::hash::Hash for Fieldless {
         ::core::hash::Hash::hash(&__self_tag, state)
     }
 }
-impl ::core::marker::StructuralPartialEq for Fieldless {}
+#[automatically_derived]
+impl ::core::marker::StructuralPartialEq for Fieldless { }
 #[automatically_derived]
 impl ::core::cmp::PartialEq for Fieldless {
     #[inline]
@@ -753,7 +772,8 @@ impl ::core::cmp::PartialEq for Fieldless {
         __self_tag == __arg1_tag
     }
 }
-impl ::core::marker::StructuralEq for Fieldless {}
+#[automatically_derived]
+impl ::core::marker::StructuralEq for Fieldless { }
 #[automatically_derived]
 impl ::core::cmp::Eq for Fieldless {
     #[inline]
@@ -838,7 +858,8 @@ impl ::core::hash::Hash for Mixed {
         }
     }
 }
-impl ::core::marker::StructuralPartialEq for Mixed {}
+#[automatically_derived]
+impl ::core::marker::StructuralPartialEq for Mixed { }
 #[automatically_derived]
 impl ::core::cmp::PartialEq for Mixed {
     #[inline]
@@ -856,7 +877,8 @@ impl ::core::cmp::PartialEq for Mixed {
             }
     }
 }
-impl ::core::marker::StructuralEq for Mixed {}
+#[automatically_derived]
+impl ::core::marker::StructuralEq for Mixed { }
 #[automatically_derived]
 impl ::core::cmp::Eq for Mixed {
     #[inline]
@@ -963,7 +985,8 @@ impl ::core::hash::Hash for Fielded {
         }
     }
 }
-impl ::core::marker::StructuralPartialEq for Fielded {}
+#[automatically_derived]
+impl ::core::marker::StructuralPartialEq for Fielded { }
 #[automatically_derived]
 impl ::core::cmp::PartialEq for Fielded {
     #[inline]
@@ -982,7 +1005,8 @@ impl ::core::cmp::PartialEq for Fielded {
             }
     }
 }
-impl ::core::marker::StructuralEq for Fielded {}
+#[automatically_derived]
+impl ::core::marker::StructuralEq for Fielded { }
 #[automatically_derived]
 impl ::core::cmp::Eq for Fielded {
     #[inline]

src/test/ui/single-use-lifetime/derive-eq.rs

@@ -0,0 +1,11 @@
+// check-pass
+
+#![deny(single_use_lifetimes)]
+
+#[derive(PartialEq, Eq)]
+struct Foo<'a, T> {
+    /// a reference to the underlying secret data that will be derefed
+    pub data: &'a mut T,
+}
+
+fn main() {}