rustc: Remove some long deprecated features:

* no_split_stack was renamed to no_stack_check
* deriving was renamed to derive
* `use foo::mod` was renamed to `use foo::self`;
* legacy lifetime definitions in closures have been replaced with `for` syntax
* `fn foo() -> &A + B` has been deprecated for some time (needs parens)
* Obsolete `for Sized?` syntax
* Obsolete `Sized? Foo` syntax
* Obsolete `|T| -> U` syntax

src/librustc_trans/trans/base.rs

@@ -428,11 +428,6 @@ pub fn set_llvm_fn_attrs(ccx: &CrateContext, attrs: &[ast::Attribute], llfn: Val
         let mut used = true;
         match &attr.name()[..] {
             "no_stack_check" => unset_split_stack(llfn),
-            "no_split_stack" => {
-                unset_split_stack(llfn);
-                ccx.sess().span_warn(attr.span,
-                                     "no_split_stack is a deprecated synonym for no_stack_check");
-            }
             "cold" => unsafe {
                 llvm::LLVMAddFunctionAttribute(llfn,
                                                llvm::FunctionIndex as c_uint,

src/libsyntax/ext/deriving/mod.rs

@@ -78,14 +78,6 @@ pub mod totalord;
 
 pub mod generic;
 
-fn expand_deprecated_deriving(cx: &mut ExtCtxt,
-                              span: Span,
-                              _: &MetaItem,
-                              _: &Item,
-                              _: &mut FnMut(P<Item>)) {
-    cx.span_err(span, "`deriving` has been renamed to `derive`");
-}
-
 fn expand_derive(cx: &mut ExtCtxt,
                  _: Span,
                  mitem: &MetaItem,
@@ -151,8 +143,6 @@ macro_rules! derive_traits {
 
             env.insert(intern("derive"),
                        Modifier(Box::new(expand_derive)));
-            env.insert(intern("deriving"),
-                       Decorator(Box::new(expand_deprecated_deriving)));
         }
 
         fn is_builtin_trait(name: &str) -> bool {

src/libsyntax/feature_gate.rs

@@ -201,7 +201,6 @@ pub const KNOWN_ATTRIBUTES: &'static [(&'static str, AttributeType)] = &[
     ("no_mangle", Normal),
     ("no_link", Normal),
     ("derive", Normal),
-    ("deriving", Normal), // deprecation err in expansion
     ("should_fail", Normal),
     ("should_panic", Normal),
     ("ignore", Normal),
@@ -259,7 +258,6 @@ pub const KNOWN_ATTRIBUTES: &'static [(&'static str, AttributeType)] = &[
     ("link_section", Whitelisted),
     ("no_builtins", Whitelisted),
     ("no_mangle", Whitelisted),
-    ("no_split_stack", Whitelisted),
     ("no_stack_check", Whitelisted),
     ("packed", Whitelisted),
     ("static_assert", Gated("static_assert",

src/libsyntax/parse/obsolete.rs

@@ -22,9 +22,6 @@ use ptr::P;
 /// The specific types of unsupported syntax
 #[derive(Copy, PartialEq, Eq, Hash)]
 pub enum ObsoleteSyntax {
-    Sized,
-    ForSized,
-    ClosureType,
     ClosureKind,
     EmptyIndex,
 }
@@ -49,27 +46,11 @@ impl<'a> ParserObsoleteMethods for parser::Parser<'a> {
     /// Reports an obsolete syntax non-fatal error.
     fn obsolete(&mut self, sp: Span, kind: ObsoleteSyntax) {
         let (kind_str, desc, error) = match kind {
-            ObsoleteSyntax::ForSized => (
-                "for Sized?",
-                "no longer required. Traits (and their `Self` type) do not have the `Sized` bound \
-                 by default",
-                true,
-            ),
-            ObsoleteSyntax::ClosureType => (
-                "`|usize| -> bool` closure type",
-                "use unboxed closures instead, no type annotation needed",
-                true,
-            ),
             ObsoleteSyntax::ClosureKind => (
                 "`:`, `&mut:`, or `&:`",
                 "rely on inference instead",
                 true,
             ),
-            ObsoleteSyntax::Sized => (
-                "`Sized? T` for removing the `Sized` bound",
-                "write `T: ?Sized` instead",
-                true,
-            ),
             ObsoleteSyntax::EmptyIndex => (
                 "[]",
                 "write `[..]` instead",