3 files changed, 18 insertions, 2 deletions
diff --git a/src/libsyntax/attr/builtin.rs b/src/libsyntax/attr/builtin.rs
index 15e480496f7..1a4b45e76b4 100644
--- a/src/libsyntax/attr/builtin.rs
+++ b/src/libsyntax/attr/builtin.rs
@@ -63,6 +63,13 @@ pub enum InlineAttr {
     Never,
 }
 
+#[derive(Copy, Clone, Hash, PartialEq, RustcEncodable, RustcDecodable)]
+pub enum OptimizeAttr {
+    None,
+    Speed,
+    Size,
+}
+
 #[derive(Copy, Clone, PartialEq)]
 pub enum UnwindAttr {
     Allowed,
diff --git a/src/libsyntax/attr/mod.rs b/src/libsyntax/attr/mod.rs
index e5ce6a3f19a..58be7c3e085 100644
--- a/src/libsyntax/attr/mod.rs
+++ b/src/libsyntax/attr/mod.rs
@@ -4,8 +4,8 @@ mod builtin;
 
 pub use self::builtin::{
     cfg_matches, contains_feature_attr, eval_condition, find_crate_name, find_deprecation,
-    find_repr_attrs, find_stability, find_unwind_attr, Deprecation, InlineAttr, IntType, ReprAttr,
-    RustcDeprecation, Stability, StabilityLevel, UnwindAttr,
+    find_repr_attrs, find_stability, find_unwind_attr, Deprecation, InlineAttr, OptimizeAttr,
+    IntType, ReprAttr, RustcDeprecation, Stability, StabilityLevel, UnwindAttr,
 };
 pub use self::IntType::*;
 pub use self::ReprAttr::*;
diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs
index 85e80f7bdaf..d74a0d5623a 100644
--- a/src/libsyntax/feature_gate.rs
+++ b/src/libsyntax/feature_gate.rs
@@ -461,6 +461,9 @@ declare_features! (
 
     // Re-Rebalance coherence
     (active, re_rebalance_coherence, "1.32.0", Some(55437), None),
+
+    // #[optimize(X)]
+    (active, optimize_attribute, "1.34.0", Some(54882), None),
 );
 
 declare_features! (
@@ -1222,6 +1225,12 @@ pub const BUILTIN_ATTRIBUTES: &[(&str, AttributeType, AttributeTemplate, Attribu
                            "#[alloc_error_handler] is an unstable feature",
                            cfg_fn!(alloc_error_handler))),
 
+    // RFC 2412
+    ("optimize", Whitelisted, template!(List: "size|speed"), Gated(Stability::Unstable,
+                               "optimize_attribute",
+                               "#[optimize] attribute is an unstable feature",
+                               cfg_fn!(optimize_attribute))),
+
     // Crate level attributes
     ("crate_name", CrateLevel, template!(NameValueStr: "name"), Ungated),
     ("crate_type", CrateLevel, template!(NameValueStr: "bin|lib|..."), Ungated),