From c14ad18ca87d34519799774a018f6d0da2df1fc2 Mon Sep 17 00:00:00 2001
From: Falk Werner <falk.werner@gmx.net>
Date: Thu, 18 Apr 2019 19:21:07 +0200
Subject: [PATCH] makes WF_CONTAINER_OF use typeof, if available

---
 lib/webfuse/core/container_of.h | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/lib/webfuse/core/container_of.h b/lib/webfuse/core/container_of.h
index fa51a26..4154d15 100644
--- a/lib/webfuse/core/container_of.h
+++ b/lib/webfuse/core/container_of.h
@@ -7,7 +7,15 @@
 #include <cstddef>
 #endif
 
+#ifdef __GNUC__
+#define WF_CONTAINER_OF(pointer, type, member) \
+    ({ \
+        const typeof( ((type *)0)->member ) * __member = (pointer); \
+        (type *)( (char *)__member - offsetof(type, member) ); \
+    })
+#else
 #define WF_CONTAINER_OF(pointer, type, member) \
     (type *)  (((char *) pointer) - offsetof(type, member))
+#endif
 
 #endif