Remove {Method,Trait}Def::is_unsafe.

They are always `false`.

compiler/rustc_builtin_macros/src/deriving/bounds.rs

@@ -19,7 +19,6 @@ pub fn expand_deriving_copy(
         path: path_std!(marker::Copy),
         additional_bounds: Vec::new(),
         generics: Bounds::empty(),
-        is_unsafe: false,
         supports_unions: true,
         methods: Vec::new(),
         associated_types: Vec::new(),

compiler/rustc_builtin_macros/src/deriving/clone.rs

@@ -81,7 +81,6 @@ pub fn expand_deriving_clone(
         path: path_std!(clone::Clone),
         additional_bounds: bounds,
         generics: Bounds::empty(),
-        is_unsafe: false,
         supports_unions: true,
         methods: vec![MethodDef {
             name: sym::clone,
@@ -90,7 +89,6 @@ pub fn expand_deriving_clone(
             args: Vec::new(),
             ret_ty: Self_,
             attributes: attrs,
-            is_unsafe: false,
             unify_fieldless_variants: false,
             combine_substructure: substructure,
         }],

compiler/rustc_builtin_macros/src/deriving/cmp/eq.rs

@@ -27,7 +27,6 @@ pub fn expand_deriving_eq(
         path: path_std!(cmp::Eq),
         additional_bounds: Vec::new(),
         generics: Bounds::empty(),
-        is_unsafe: false,
         supports_unions: true,
         methods: vec![MethodDef {
             name: sym::assert_receiver_is_total_eq,
@@ -36,7 +35,6 @@ pub fn expand_deriving_eq(
             args: vec![],
             ret_ty: nil_ty(),
             attributes: attrs,
-            is_unsafe: false,
             unify_fieldless_variants: true,
             combine_substructure: combine_substructure(Box::new(|a, b, c| {
                 cs_total_eq_assert(a, b, c)

compiler/rustc_builtin_macros/src/deriving/cmp/ord.rs

@@ -23,7 +23,6 @@ pub fn expand_deriving_ord(
         path: path_std!(cmp::Ord),
         additional_bounds: Vec::new(),
         generics: Bounds::empty(),
-        is_unsafe: false,
         supports_unions: false,
         methods: vec![MethodDef {
             name: sym::cmp,
@@ -32,7 +31,6 @@ pub fn expand_deriving_ord(
             args: vec![(borrowed_self(), sym::other)],
             ret_ty: Literal(path_std!(cmp::Ordering)),
             attributes: attrs,
-            is_unsafe: false,
             unify_fieldless_variants: true,
             combine_substructure: combine_substructure(Box::new(|a, b, c| cs_cmp(a, b, c))),
         }],

compiler/rustc_builtin_macros/src/deriving/cmp/partial_eq.rs

@@ -73,7 +73,6 @@ pub fn expand_deriving_partial_eq(
                 args: vec![(borrowed_self(), sym::other)],
                 ret_ty: Literal(path_local!(bool)),
                 attributes: attrs,
-                is_unsafe: false,
                 unify_fieldless_variants: true,
                 combine_substructure: combine_substructure(Box::new(|a, b, c| $f(a, b, c))),
             }
@@ -102,7 +101,6 @@ pub fn expand_deriving_partial_eq(
         path: path_std!(cmp::PartialEq),
         additional_bounds: Vec::new(),
         generics: Bounds::empty(),
-        is_unsafe: false,
         supports_unions: false,
         methods,
         associated_types: Vec::new(),

compiler/rustc_builtin_macros/src/deriving/cmp/partial_ord.rs

@@ -33,7 +33,6 @@ pub fn expand_deriving_partial_ord(
         args: vec![(borrowed_self(), sym::other)],
         ret_ty,
         attributes: attrs,
-        is_unsafe: false,
         unify_fieldless_variants: true,
         combine_substructure: combine_substructure(Box::new(|cx, span, substr| {
             cs_partial_cmp(cx, span, substr)
@@ -46,7 +45,6 @@ pub fn expand_deriving_partial_ord(
         path: path_std!(cmp::PartialOrd),
         additional_bounds: vec![],
         generics: Bounds::empty(),
-        is_unsafe: false,
         supports_unions: false,
         methods: vec![partial_cmp_def],
         associated_types: Vec::new(),

compiler/rustc_builtin_macros/src/deriving/debug.rs

@@ -25,7 +25,6 @@ pub fn expand_deriving_debug(
         path: path_std!(fmt::Debug),
         additional_bounds: Vec::new(),
         generics: Bounds::empty(),
-        is_unsafe: false,
         supports_unions: false,
         methods: vec![MethodDef {
             name: sym::fmt,
@@ -34,7 +33,6 @@ pub fn expand_deriving_debug(
             args: vec![(fmtr, sym::f)],
             ret_ty: Literal(path_std!(fmt::Result)),
             attributes: Vec::new(),
-            is_unsafe: false,
             unify_fieldless_variants: false,
             combine_substructure: combine_substructure(Box::new(|a, b, c| {
                 show_substructure(a, b, c)

compiler/rustc_builtin_macros/src/deriving/decodable.rs

@@ -26,7 +26,6 @@ pub fn expand_deriving_rustc_decodable(
         path: Path::new_(vec![krate, sym::Decodable], None, vec![], PathKind::Global),
         additional_bounds: Vec::new(),
         generics: Bounds::empty(),
-        is_unsafe: false,
         supports_unions: false,
         methods: vec![MethodDef {
             name: sym::decode,
@@ -56,7 +55,6 @@ pub fn expand_deriving_rustc_decodable(
                 PathKind::Std,
             )),
             attributes: Vec::new(),
-            is_unsafe: false,
             unify_fieldless_variants: false,
             combine_substructure: combine_substructure(Box::new(|a, b, c| {
                 decodable_substructure(a, b, c, krate)

compiler/rustc_builtin_macros/src/deriving/default.rs

@@ -30,7 +30,6 @@ pub fn expand_deriving_default(
         path: Path::new(vec![kw::Default, sym::Default]),
         additional_bounds: Vec::new(),
         generics: Bounds::empty(),
-        is_unsafe: false,
         supports_unions: false,
         methods: vec![MethodDef {
             name: kw::Default,
@@ -39,7 +38,6 @@ pub fn expand_deriving_default(
             args: Vec::new(),
             ret_ty: Self_,
             attributes: attrs,
-            is_unsafe: false,
             unify_fieldless_variants: false,
             combine_substructure: combine_substructure(Box::new(|cx, trait_span, substr| {
                 match substr.fields {

compiler/rustc_builtin_macros/src/deriving/encodable.rs

@@ -111,7 +111,6 @@ pub fn expand_deriving_rustc_encodable(
         path: Path::new_(vec![krate, sym::Encodable], None, vec![], PathKind::Global),
         additional_bounds: Vec::new(),
         generics: Bounds::empty(),
-        is_unsafe: false,
         supports_unions: false,
         methods: vec![MethodDef {
             name: sym::encode,
@@ -141,7 +140,6 @@ pub fn expand_deriving_rustc_encodable(
                 PathKind::Std,
             )),
             attributes: Vec::new(),
-            is_unsafe: false,
             unify_fieldless_variants: false,
             combine_substructure: combine_substructure(Box::new(|a, b, c| {
                 encodable_substructure(a, b, c, krate)

compiler/rustc_builtin_macros/src/deriving/generic/mod.rs

@@ -210,9 +210,6 @@ pub struct TraitDef<'a> {
     /// Any extra lifetimes and/or bounds, e.g., `D: serialize::Decoder`
     pub generics: Bounds,
 
-    /// Is it an `unsafe` trait?
-    pub is_unsafe: bool,
-
     /// Can this trait be derived for unions?
     pub supports_unions: bool,
 
@@ -240,9 +237,6 @@ pub struct MethodDef<'a> {
 
     pub attributes: Vec<ast::Attribute>,
 
-    // Is it an `unsafe fn`?
-    pub is_unsafe: bool,
-
     /// Can we combine fieldless variants for enums into a single match arm?
     pub unify_fieldless_variants: bool,
 
@@ -717,14 +711,12 @@ impl<'a> TraitDef<'a> {
         let mut a = vec![attr, unused_qual];
         a.extend(self.attributes.iter().cloned());
 
-        let unsafety = if self.is_unsafe { ast::Unsafe::Yes(self.span) } else { ast::Unsafe::No };
-
         cx.item(
             self.span,
             Ident::empty(),
             a,
             ast::ItemKind::Impl(Box::new(ast::Impl {
-                unsafety,
+                unsafety: ast::Unsafe::No,
                 polarity: ast::ImplPolarity::Positive,
                 defaultness: ast::Defaultness::Final,
                 constness: ast::Const::No,
@@ -939,15 +931,9 @@ impl<'a> MethodDef<'a> {
         let fn_decl = cx.fn_decl(args, ast::FnRetTy::Ty(ret_type));
         let body_block = cx.block_expr(body);
 
-        let unsafety = if self.is_unsafe { ast::Unsafe::Yes(span) } else { ast::Unsafe::No };
-
         let trait_lo_sp = span.shrink_to_lo();
 
-        let sig = ast::FnSig {
+        let sig = ast::FnSig { header: ast::FnHeader::default(), decl: fn_decl, span };
-            header: ast::FnHeader { unsafety, ext: ast::Extern::None, ..ast::FnHeader::default() },
-            decl: fn_decl,
-            span,
-        };
         let defaultness = ast::Defaultness::Final;
 
         // Create the method.

compiler/rustc_builtin_macros/src/deriving/hash.rs

@@ -26,7 +26,6 @@ pub fn expand_deriving_hash(
         path,
         additional_bounds: Vec::new(),
         generics: Bounds::empty(),
-        is_unsafe: false,
         supports_unions: false,
         methods: vec![MethodDef {
             name: sym::hash,
@@ -35,7 +34,6 @@ pub fn expand_deriving_hash(
             args: vec![(Ptr(Box::new(Literal(arg)), Borrowed(None, Mutability::Mut)), sym::state)],
             ret_ty: nil_ty(),
             attributes: vec![],
-            is_unsafe: false,
             unify_fieldless_variants: true,
             combine_substructure: combine_substructure(Box::new(|a, b, c| {
                 hash_substructure(a, b, c)