From 844be5eaa116820b14642b0893c288ba13a99e7f Mon Sep 17 00:00:00 2001
From: Amanieu d'Antras <amanieu@gmail.com>
Date: Tue, 20 Sep 2022 15:12:39 +0800
Subject: [PATCH] Fix `ReentrantMutexGuard::try_map` signature

This previously incorrectly used `&mut T` instead of `&T`.

Fixes #354
---
 lock_api/src/remutex.rs | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lock_api/src/remutex.rs b/lock_api/src/remutex.rs
index fa0e934d..c450798d 100644
--- a/lock_api/src/remutex.rs
+++ b/lock_api/src/remutex.rs
@@ -654,10 +654,10 @@ impl<'a, R: RawMutex + 'a, G: GetThreadId + 'a, T: ?Sized + 'a> ReentrantMutexGu
         f: F,
     ) -> Result<MappedReentrantMutexGuard<'a, R, G, U>, Self>
     where
-        F: FnOnce(&mut T) -> Option<&mut U>,
+        F: FnOnce(&T) -> Option<&U>,
     {
         let raw = &s.remutex.raw;
-        let data = match f(unsafe { &mut *s.remutex.data.get() }) {
+        let data = match f(unsafe { &*s.remutex.data.get() }) {
             Some(data) => data,
             None => return Err(s),
         };