15 files changed, 25 insertions, 1 deletions

diff --git a/src/libsyntax/ext/deriving/bounds.rs b/src/libsyntax/ext/deriving/bounds.rs
index 71b6184390a..87a6d0805b5 100644
--- a/src/libsyntax/ext/deriving/bounds.rs
+++ b/src/libsyntax/ext/deriving/bounds.rs
@@ -40,6 +40,7 @@ pub fn expand_deriving_copy(cx: &mut ExtCtxt,
         path: path,
         additional_bounds: Vec::new(),
         generics: LifetimeBounds::empty(),
+        is_unsafe: false,
         methods: Vec::new(),
         associated_types: Vec::new(),
     };
diff --git a/src/libsyntax/ext/deriving/clone.rs b/src/libsyntax/ext/deriving/clone.rs
index 9261c0162c7..f1a2983479c 100644
--- a/src/libsyntax/ext/deriving/clone.rs
+++ b/src/libsyntax/ext/deriving/clone.rs
@@ -31,6 +31,7 @@ pub fn expand_deriving_clone(cx: &mut ExtCtxt,
         path: path_std!(cx, core::clone::Clone),
         additional_bounds: Vec::new(),
         generics: LifetimeBounds::empty(),
+        is_unsafe: false,
         methods: vec!(
             MethodDef {
                 name: "clone",
diff --git a/src/libsyntax/ext/deriving/cmp/eq.rs b/src/libsyntax/ext/deriving/cmp/eq.rs
index b370757e8fb..bd6b27fb44e 100644
--- a/src/libsyntax/ext/deriving/cmp/eq.rs
+++ b/src/libsyntax/ext/deriving/cmp/eq.rs
@@ -51,6 +51,7 @@ pub fn expand_deriving_eq(cx: &mut ExtCtxt,
         path: path_std!(cx, core::cmp::Eq),
         additional_bounds: Vec::new(),
         generics: LifetimeBounds::empty(),
+        is_unsafe: false,
         methods: vec!(
             MethodDef {
                 name: "assert_receiver_is_total_eq",
diff --git a/src/libsyntax/ext/deriving/cmp/ord.rs b/src/libsyntax/ext/deriving/cmp/ord.rs
index 815448ac610..ff36e01d6cc 100644
--- a/src/libsyntax/ext/deriving/cmp/ord.rs
+++ b/src/libsyntax/ext/deriving/cmp/ord.rs
@@ -32,6 +32,7 @@ pub fn expand_deriving_ord(cx: &mut ExtCtxt,
         path: path_std!(cx, core::cmp::Ord),
         additional_bounds: Vec::new(),
         generics: LifetimeBounds::empty(),
+        is_unsafe: false,
         methods: vec!(
             MethodDef {
                 name: "cmp",
diff --git a/src/libsyntax/ext/deriving/cmp/partial_eq.rs b/src/libsyntax/ext/deriving/cmp/partial_eq.rs
index e5d6408ca1b..495761c499b 100644
--- a/src/libsyntax/ext/deriving/cmp/partial_eq.rs
+++ b/src/libsyntax/ext/deriving/cmp/partial_eq.rs
@@ -85,6 +85,7 @@ pub fn expand_deriving_partial_eq(cx: &mut ExtCtxt,
         path: path_std!(cx, core::cmp::PartialEq),
         additional_bounds: Vec::new(),
         generics: LifetimeBounds::empty(),
+        is_unsafe: false,
         methods: vec!(
             md!("eq", cs_eq),
             md!("ne", cs_ne)
diff --git a/src/libsyntax/ext/deriving/cmp/partial_ord.rs b/src/libsyntax/ext/deriving/cmp/partial_ord.rs
index a11e9f473a4..084e3ef3f91 100644
--- a/src/libsyntax/ext/deriving/cmp/partial_ord.rs
+++ b/src/libsyntax/ext/deriving/cmp/partial_ord.rs
@@ -73,6 +73,7 @@ pub fn expand_deriving_partial_ord(cx: &mut ExtCtxt,
         path: path_std!(cx, core::cmp::PartialOrd),
         additional_bounds: vec![],
         generics: LifetimeBounds::empty(),
+        is_unsafe: false,
         methods: vec![
             partial_cmp_def,
             md!("lt", true, false),
diff --git a/src/libsyntax/ext/deriving/decodable.rs b/src/libsyntax/ext/deriving/decodable.rs
index 99fac991e7f..0fdcbec8447 100644
--- a/src/libsyntax/ext/deriving/decodable.rs
+++ b/src/libsyntax/ext/deriving/decodable.rs
@@ -59,6 +59,7 @@ fn expand_deriving_decodable_imp(cx: &mut ExtCtxt,
         path: Path::new_(vec!(krate, "Decodable"), None, vec!(), true),
         additional_bounds: Vec::new(),
         generics: LifetimeBounds::empty(),
+        is_unsafe: false,
         methods: vec!(
             MethodDef {
                 name: "decode",
diff --git a/src/libsyntax/ext/deriving/default.rs b/src/libsyntax/ext/deriving/default.rs
index 3f4e9da0ed5..6a25088782a 100644
--- a/src/libsyntax/ext/deriving/default.rs
+++ b/src/libsyntax/ext/deriving/default.rs
@@ -31,6 +31,7 @@ pub fn expand_deriving_default(cx: &mut ExtCtxt,
         path: path_std!(cx, core::default::Default),
         additional_bounds: Vec::new(),
         generics: LifetimeBounds::empty(),
+        is_unsafe: false,
         methods: vec!(
             MethodDef {
                 name: "default",
diff --git a/src/libsyntax/ext/deriving/encodable.rs b/src/libsyntax/ext/deriving/encodable.rs
index 3c77effe5f5..786739938e5 100644
--- a/src/libsyntax/ext/deriving/encodable.rs
+++ b/src/libsyntax/ext/deriving/encodable.rs
@@ -135,6 +135,7 @@ fn expand_deriving_encodable_imp(cx: &mut ExtCtxt,
         path: Path::new_(vec!(krate, "Encodable"), None, vec!(), true),
         additional_bounds: Vec::new(),
         generics: LifetimeBounds::empty(),
+        is_unsafe: false,
         methods: vec!(
             MethodDef {
                 name: "encode",
diff --git a/src/libsyntax/ext/deriving/generic/mod.rs b/src/libsyntax/ext/deriving/generic/mod.rs
index 3196380ec6c..9fc2745cf92 100644
--- a/src/libsyntax/ext/deriving/generic/mod.rs
+++ b/src/libsyntax/ext/deriving/generic/mod.rs
@@ -229,6 +229,9 @@ pub struct TraitDef<'a> {
     /// Any extra lifetimes and/or bounds, e.g. `D: serialize::Decoder`
     pub generics: LifetimeBounds<'a>,
 
+    /// Is it an `unsafe` trait?
+    pub is_unsafe: bool,
+
     pub methods: Vec<MethodDef<'a>>,
 
     pub associated_types: Vec<(ast::Ident, Ty<'a>)>,
@@ -625,11 +628,18 @@ impl<'a> TraitDef<'a> {
                                            InternedString::new("unused_qualifications"))]));
         let mut a = vec![attr, unused_qual];
         a.extend(self.attributes.iter().cloned());
+
+        let unsafety = if self.is_unsafe {
+            ast::Unsafety::Unsafe
+        } else {
+            ast::Unsafety::Normal
+        };
+
         cx.item(
             self.span,
             ident,
             a,
-            ast::ItemImpl(ast::Unsafety::Normal,
+            ast::ItemImpl(unsafety,
                           ast::ImplPolarity::Positive,
                           trait_generics,
                           opt_trait_ref,
diff --git a/src/libsyntax/ext/deriving/hash.rs b/src/libsyntax/ext/deriving/hash.rs
index 97c50ed1eea..96be774ebdc 100644
--- a/src/libsyntax/ext/deriving/hash.rs
+++ b/src/libsyntax/ext/deriving/hash.rs
@@ -32,6 +32,7 @@ pub fn expand_deriving_hash(cx: &mut ExtCtxt,
         path: path,
         additional_bounds: Vec::new(),
         generics: LifetimeBounds::empty(),
+        is_unsafe: false,
         methods: vec!(
             MethodDef {
                 name: "hash",
diff --git a/src/libsyntax/ext/deriving/primitive.rs b/src/libsyntax/ext/deriving/primitive.rs
index 5eb98d3aa15..5d3cc50557c 100644
--- a/src/libsyntax/ext/deriving/primitive.rs
+++ b/src/libsyntax/ext/deriving/primitive.rs
@@ -32,6 +32,7 @@ pub fn expand_deriving_from_primitive(cx: &mut ExtCtxt,
         path: path_std!(cx, core::num::FromPrimitive),
         additional_bounds: Vec::new(),
         generics: LifetimeBounds::empty(),
+        is_unsafe: false,
         methods: vec!(
             MethodDef {
                 name: "from_i64",
diff --git a/src/libsyntax/ext/deriving/show.rs b/src/libsyntax/ext/deriving/show.rs
index 3a478884c6a..4d70ca1ebf1 100644
--- a/src/libsyntax/ext/deriving/show.rs
+++ b/src/libsyntax/ext/deriving/show.rs
@@ -34,6 +34,7 @@ pub fn expand_deriving_show(cx: &mut ExtCtxt,
         path: path_std!(cx, core::fmt::Debug),
         additional_bounds: Vec::new(),
         generics: LifetimeBounds::empty(),
+        is_unsafe: false,
         methods: vec![
             MethodDef {
                 name: "fmt",
diff --git a/src/test/auxiliary/custom_derive_plugin.rs b/src/test/auxiliary/custom_derive_plugin.rs
index 8c1445a172d..44ab4cc89a0 100644
--- a/src/test/auxiliary/custom_derive_plugin.rs
+++ b/src/test/auxiliary/custom_derive_plugin.rs
@@ -46,6 +46,7 @@ fn expand(cx: &mut ExtCtxt,
         additional_bounds: vec![],
         generics: LifetimeBounds::empty(),
         associated_types: vec![],
+        is_unsafe: false,
         methods: vec![
             MethodDef {
                 name: "total_sum",
diff --git a/src/test/auxiliary/custom_derive_plugin_attr.rs b/src/test/auxiliary/custom_derive_plugin_attr.rs
index 01fde91fef5..82d0edfb163 100644
--- a/src/test/auxiliary/custom_derive_plugin_attr.rs
+++ b/src/test/auxiliary/custom_derive_plugin_attr.rs
@@ -48,6 +48,7 @@ fn expand(cx: &mut ExtCtxt,
         additional_bounds: vec![],
         generics: LifetimeBounds::empty(),
         associated_types: vec![],
+        is_unsafe: false,
         methods: vec![
             MethodDef {
                 name: "total_sum",