From 84d1f6aa82123c2951042aff99e43bdb894d3d81 Mon Sep 17 00:00:00 2001
From: Simonas Kazlauskas <git@kazlauskas.me>
Date: Wed, 8 Mar 2017 22:17:42 +0200
Subject: [PATCH] Do not bother creating StorageLive for TyNever

Keeps MIR cleaner, `StorageLive(_: !)` makes no sense anyway.
---
 src/librustc_mir/build/expr/as_temp.rs | 2 +-
 src/test/mir-opt/issue-38669.rs        | 1 -
 2 files changed, 1 insertion(+), 2 deletions(-)

diff --git a/src/librustc_mir/build/expr/as_temp.rs b/src/librustc_mir/build/expr/as_temp.rs
index 69b9570200921..42d9ab4d2bf27 100644
--- a/src/librustc_mir/build/expr/as_temp.rs
+++ b/src/librustc_mir/build/expr/as_temp.rs
@@ -55,7 +55,7 @@ impl<'a, 'gcx, 'tcx> Builder<'a, 'gcx, 'tcx> {
 (https://github.com/rust-lang/rust/issues/39283)");
         }
 
-        if temp_lifetime.is_some() {
+        if !expr_ty.is_never() && temp_lifetime.is_some() {
             this.cfg.push(block, Statement {
                 source_info: source_info,
                 kind: StatementKind::StorageLive(temp.clone())
diff --git a/src/test/mir-opt/issue-38669.rs b/src/test/mir-opt/issue-38669.rs
index 1d452907cf59a..fbbffe8953b38 100644
--- a/src/test/mir-opt/issue-38669.rs
+++ b/src/test/mir-opt/issue-38669.rs
@@ -35,7 +35,6 @@ fn main() {
 //     }
 //
 //     bb2: {
-//         StorageLive(_6);
 //         _0 = ();
 //         StorageDead(_4);
 //         StorageDead(_1);