From 5d6c5132c130ac1250a17048249815ef1f5939ac Mon Sep 17 00:00:00 2001
From: Anthony Ramine <nox@nox.paris>
Date: Sat, 4 Apr 2020 20:29:25 +0200
Subject: [PATCH] Don't use transmute to create PaintOrder values

I checked that rustc optimises the code just as well as with the transmute.

https://rust.godbolt.org/z/w6UJN4
---
 components/style/values/specified/svg.rs | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/components/style/values/specified/svg.rs b/components/style/values/specified/svg.rs
index 6ae1eac2d4a..e603ddfda07 100644
--- a/components/style/values/specified/svg.rs
+++ b/components/style/values/specified/svg.rs
@@ -146,8 +146,13 @@ impl SVGPaintOrder {
 
     /// Get variant of `paint-order`
     pub fn order_at(&self, pos: u8) -> PaintOrder {
-        // Safe because PaintOrder covers all possible patterns.
-        unsafe { std::mem::transmute((self.0 >> pos * PAINT_ORDER_SHIFT) & PAINT_ORDER_MASK) }
+        match (self.0 >> pos * PAINT_ORDER_SHIFT) & PAINT_ORDER_MASK {
+            0 => PaintOrder::Normal,
+            1 => PaintOrder::Fill,
+            2 => PaintOrder::Stroke,
+            3 => PaintOrder::Markers,
+            _ => unreachable!("this cannot happen"),
+        }
     }
 }