From 921d1aeebada477a8ebe35b75e44e9dbecae8842 Mon Sep 17 00:00:00 2001
From: Anthony Ramine <n.oxyde@gmail.com>
Date: Fri, 9 Feb 2018 22:54:33 +0100
Subject: [PATCH] =?UTF-8?q?Make=20AnimationValue::id=20be=20just=20a=20poi?=
 =?UTF-8?q?nter=20cast=20=F0=9F=90=89=F0=9F=90=B2?=
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Now that PropertyDeclaration and AnimationValue have the same discriminants,
that means the trick found in PropertyDeclaration::id can be done in
AnimationValue::id.
---
 components/malloc_size_of/lib.rs                            | 2 +-
 .../style/properties/helpers/animated_properties.mako.rs    | 6 ++++--
 2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/components/malloc_size_of/lib.rs b/components/malloc_size_of/lib.rs
index 3801669ab5d..5e97a2709dc 100644
--- a/components/malloc_size_of/lib.rs
+++ b/components/malloc_size_of/lib.rs
@@ -58,9 +58,9 @@ extern crate smallvec;
 extern crate string_cache;
 #[cfg(feature = "url")]
 extern crate url;
+extern crate void;
 #[cfg(feature = "webrender_api")]
 extern crate webrender_api;
-extern crate void;
 #[cfg(feature = "servo")]
 extern crate xml5ever;
 
diff --git a/components/style/properties/helpers/animated_properties.mako.rs b/components/style/properties/helpers/animated_properties.mako.rs
index 703b6be9fe5..a5f1abd935e 100644
--- a/components/style/properties/helpers/animated_properties.mako.rs
+++ b/components/style/properties/helpers/animated_properties.mako.rs
@@ -364,7 +364,8 @@ pub enum AnimationValue {
 impl AnimationValue {
     /// Returns the longhand id this animated value corresponds to.
     pub fn id(&self) -> LonghandId {
-        match *self {
+        let id = unsafe { *(self as *const _ as *const LonghandId) };
+        debug_assert_eq!(id, match *self {
             % for prop in data.longhands:
             % if prop.animatable:
             AnimationValue::${prop.camel_case}(..) => LonghandId::${prop.camel_case},
@@ -372,7 +373,8 @@ impl AnimationValue {
             AnimationValue::${prop.camel_case}(void) => void::unreachable(void),
             % endif
             % endfor
-        }
+        });
+        id
     }
 
     /// "Uncompute" this animation value in order to be used inside the CSS