Auto merge of #46971 - green-s:master, r=alexcrichton

bors · bors · commit 4a7c072fa61b · 2017-12-25T12:55:52.000Z
Update compiler_builtins Fixes #46822 (see rust-lang/compiler-builtins#219)
diff --git a/src/libcompiler_builtins b/src/libcompiler_builtins
@@ -1 +1 @@
-Subproject commit 000d06a57a622eb4db4a15d0f76db48571f4d8e4
+Subproject commit 3a9ba44406dd088603b33740cbc18ccfde1c001b
