From: Simon Marchi <simon.marchi@efficios.com>
Date: Tue, 20 Aug 2019 01:51:52 +0000 (-0400)
Subject: Make bitfield.h C++-friendly
X-Git-Tag: v2.12.0-pre~32
X-Git-Url: http://git.lttng.org/?p=lttng-modules.git;a=commitdiff_plain;h=ff0d3a20659704a3762b0394844f42a89afbe246

Make bitfield.h C++-friendly

This patch changes bitfield.h to be usable in C++11.

It will probably never be compiled as C++ in the context of
lttng-modules, but this is just to keep things sync'ed across projects.

Signed-off-by: Simon Marchi <simon.marchi@efficios.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
---

diff --git a/lib/bitfield.h b/lib/bitfield.h
index a9e268b4..7d5eaeaa 100644
--- a/lib/bitfield.h
+++ b/lib/bitfield.h
@@ -55,8 +55,12 @@
  * Produce a build-time error if the condition `cond` is non-zero.
  * Evaluates as a size_t expression.
  */
+#ifdef __cplusplus
+#define _BT_BUILD_ASSERT(cond) ([]{static_assert((cond), "");}, 0)
+#else
 #define _BT_BUILD_ASSERT(cond)					\
 	sizeof(struct { int f:(2 * !!(cond) - 1); })
+#endif
 
 /*
  * Cast value `v` to an unsigned integer of the same size as `v`.
@@ -362,7 +366,7 @@ do {									\
 do {									\
 	__typeof__(*(vptr)) *_vptr = (vptr);				\
 	__typeof__(*_vptr) _v;						\
-	type *_ptr = (void *) (ptr);					\
+	type *_ptr = (type *) (ptr);					\
 	unsigned long _start = (start), _length = (length);		\
 	type _mask, _cmask;						\
 	unsigned long _ts = sizeof(type) * CHAR_BIT; /* type size */	\