From 942831eef4ddc75c72e3f9921a219a00f1622082 Mon Sep 17 00:00:00 2001
From: Jethro Beekman <jethro@fortanix.com>
Date: Tue, 23 Apr 2019 10:06:27 -0700
Subject: [PATCH] Debug-print error when using rtunwrap

---
 src/libstd/sys_common/mod.rs | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/src/libstd/sys_common/mod.rs b/src/libstd/sys_common/mod.rs
index 6260c3b77ff..78e15994264 100644
--- a/src/libstd/sys_common/mod.rs
+++ b/src/libstd/sys_common/mod.rs
@@ -30,10 +30,12 @@ macro_rules! rtassert {
 
 #[allow(unused_macros)] // not used on all platforms
 macro_rules! rtunwrap {
-    ($ok:ident, $e:expr) => (if let $ok(v) = $e {
-        v
-    } else {
-        rtabort!(concat!("unwrap failed: ", stringify!($e)));
+    ($ok:ident, $e:expr) => (match $e {
+        $ok(v) => v,
+        ref err => {
+            let err = err.as_ref().map(|_|()); // map Ok/Some which might not be Debug
+            rtabort!(concat!("unwrap failed: ", stringify!($e), " = {:?}"), err)
+        },
     })
 }
 
-- 
2.44.0