From 7fa87f2535a2b0b7ade1b85c470d5503b3bfdce3 Mon Sep 17 00:00:00 2001
From: Deadbeef <ent3rm4n@gmail.com>
Date: Tue, 15 Feb 2022 22:22:37 +1100
Subject: [PATCH] Clarify confusing UB statement in MIR

---
 compiler/rustc_middle/src/mir/mod.rs | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/compiler/rustc_middle/src/mir/mod.rs b/compiler/rustc_middle/src/mir/mod.rs
index 0688d7d2569f5..2d6afbe1130fa 100644
--- a/compiler/rustc_middle/src/mir/mod.rs
+++ b/compiler/rustc_middle/src/mir/mod.rs
@@ -2270,11 +2270,13 @@ pub enum BinOp {
     Mul,
     /// The `/` operator (division)
     ///
-    /// Division by zero is UB.
+    /// Division by zero is UB, because the compiler should have inserted checks
+    /// prior to this.
     Div,
     /// The `%` operator (modulus)
     ///
-    /// Using zero as the modulus (second operand) is UB.
+    /// Using zero as the modulus (second operand) is UB, because the compiler
+    /// should have inserted checks prior to this.
     Rem,
     /// The `^` operator (bitwise xor)
     BitXor,