From 031ece570138435e3438166ee49b13b574bce25a Mon Sep 17 00:00:00 2001
From: Olivier Dion <odion@efficios.com>
Date: Thu, 21 Nov 2024 11:54:55 -0500
Subject: [PATCH] Document cmm_cast_volatile

Change-Id: I3ce8df69a967b3bdaf940c4db06fd775e5b9eccb
Signed-off-by: Olivier Dion <odion@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---
 include/urcu/compiler.h | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/include/urcu/compiler.h b/include/urcu/compiler.h
index 6254252..e027c13 100644
--- a/include/urcu/compiler.h
+++ b/include/urcu/compiler.h
@@ -193,6 +193,13 @@
 
 /*
  * Helper to add the volatile qualifier to a pointer.
+ *
+ * This is used to enforce volatile accesses even when using atomic
+ * builtins. Indeed, C11 atomic operations all work on volatile memory
+ * accesses, but this is not documented for compiler atomic builtins.
+ *
+ * This could prevent certain classes of optimization from the compiler such
+ * as load/store fusing.
  */
 #if defined __cplusplus
 template <typename T>
-- 
2.39.5