Document cmm_cast_volatile

Change-Id: I3ce8df69a967b3bdaf940c4db06fd775e5b9eccb
Signed-off-by: Olivier Dion <odion@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>

diff --git a/include/urcu/compiler.h b/include/urcu/compiler.h
index 6254252ca8350dc4aabe134dc7665a89ea9a5fdf..e027c130100ea00b2078601317ba2bdca3a5c84a 100644 (file)
--- 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>