From d9ac84d05fc58aa82b4c4306f42231bb6aeb9226 Mon Sep 17 00:00:00 2001
From: David Cook <divergentdave@gmail.com>
Date: Thu, 23 Apr 2020 20:00:09 -0500
Subject: [PATCH] Add message before dumping alloc

---
 src/diagnostics.rs | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/diagnostics.rs b/src/diagnostics.rs
index 565db7b178a..e72232323ba 100644
--- a/src/diagnostics.rs
+++ b/src/diagnostics.rs
@@ -118,7 +118,12 @@ pub fn report_error<'tcx, 'mir>(
     let result = report_msg(ecx, &format!("{}: {}", title, msg), msg, helps, true);
 
     if let UndefinedBehavior(UndefinedBehaviorInfo::InvalidUndefBytes(Some(ptr))) = e.kind {
+        eprintln!(
+            "Uninitialized read occurred at offset 0x{:x} into this allocation:",
+            ptr.offset.bytes(),
+        );
         ecx.memory.dump_alloc(ptr.alloc_id);
+        eprintln!();
     }
 
     result
-- 
2.44.0