[libc-commits] [libc] [libc] Add template deduction guide for cpp::lock_guard. (PR #91589)

[via libc-commits]

https://github.com/lntue created https://github.com/llvm/llvm-project/pull/91589

Fix ctad-maybe-unsupported warnings for `cpp::lock_guard`.

>From 53ee829147f98b95a639d15b65db447fa6b23b48 Mon Sep 17 00:00:00 2001
From: Tue Ly <lntue at google.com>
Date: Thu, 9 May 2024 09:20:51 -0400
Subject: [PATCH] [libc] Add template deduction guide for cpp::lock_guard.

---
 libc/src/__support/CPP/mutex.h | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/libc/src/__support/CPP/mutex.h b/libc/src/__support/CPP/mutex.h
index 345816fae2336..ff9c9f43a43cc 100644
--- a/libc/src/__support/CPP/mutex.h
+++ b/libc/src/__support/CPP/mutex.h
@@ -40,6 +40,9 @@ template <typename MutexType> class lock_guard {
   lock_guard(const lock_guard &) = delete;
 };
 
+// Deduction guide for lock_guard to suppress CTAD warnings.
+template <typename T> lock_guard(T &) -> lock_guard<T>;
+
 } // namespace cpp
 } // namespace LIBC_NAMESPACE