[PATCH 5/8] liblockdep: Fix 'unused value' warnings

From: Levin, Alexander
Date: Fri Jul 29 2016 - 23:03:34 EST


From: Ben Hutchings <ben@xxxxxxxxxxxxxxx>

liblockdep defines various macros that may expand to an expression
with no effect, while the in-kernel definition does have an effect.
This results in warnings from gcc when -Wunused-value is enabled, and
is is enabled by -Wall. Fix this by introducing trivial functions,
as function return values are generally allowed to be ignored.

Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxx>
---
tools/lib/lockdep/uinclude/linux/debug_locks.h | 2 +-
tools/lib/lockdep/uinclude/linux/kernel.h | 12 +++++++++---
tools/lib/lockdep/uinclude/linux/lockdep.h | 6 +++++-
3 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/tools/lib/lockdep/uinclude/linux/debug_locks.h b/tools/lib/lockdep/uinclude/linux/debug_locks.h
index f38eb64..1d4fbec 100644
--- a/tools/lib/lockdep/uinclude/linux/debug_locks.h
+++ b/tools/lib/lockdep/uinclude/linux/debug_locks.h
@@ -4,7 +4,7 @@
#include <stddef.h>
#include <linux/compiler.h>

-#define DEBUG_LOCKS_WARN_ON(x) (x)
+#define DEBUG_LOCKS_WARN_ON(x) WARN_ON(x)

extern bool debug_locks;
extern bool debug_locks_silent;
diff --git a/tools/lib/lockdep/uinclude/linux/kernel.h b/tools/lib/lockdep/uinclude/linux/kernel.h
index da87bd9..021cff4 100644
--- a/tools/lib/lockdep/uinclude/linux/kernel.h
+++ b/tools/lib/lockdep/uinclude/linux/kernel.h
@@ -22,10 +22,16 @@
_max1 > _max2 ? _max1 : _max2; })

#define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
-#define WARN_ON(x) (x)
-#define WARN_ON_ONCE(x) (x)
+
+static inline int lockdep_warn(int condition)
+{
+ return condition;
+}
+#define WARN_ON(x) lockdep_warn(x)
+#define WARN_ON_ONCE(x) WARN_ON(x)
+#define WARN(x, y...) WARN_ON(x)
+
#define likely(x) (x)
-#define WARN(x, y...) (x)
#define uninitialized_var(x) x
#define __init
#define noinline
diff --git a/tools/lib/lockdep/uinclude/linux/lockdep.h b/tools/lib/lockdep/uinclude/linux/lockdep.h
index d302142..d107903 100644
--- a/tools/lib/lockdep/uinclude/linux/lockdep.h
+++ b/tools/lib/lockdep/uinclude/linux/lockdep.h
@@ -29,7 +29,11 @@ extern struct task_struct *__curr(void);

#define current (__curr())

-#define debug_locks_off() 1
+static inline int debug_locks_off(void)
+{
+ return 1;
+}
+
#define task_pid_nr(tsk) ((tsk)->pid)

#define KSYM_NAME_LEN 128
--
2.7.4