#ifndef __has_feature
#define __has_feature(x) 0
#endif
+#ifndef __has_extension
+ #define __has_extension(x) 0
+#endif
#if __GNUC__ && !__CHECKER__
#define NO_RETURN __attribute__((__noreturn__))
#define OVS_EXCLUDED(...) __attribute__((locks_excluded(__VA_ARGS__)))
#define OVS_ACQ_BEFORE(...) __attribute__((acquired_before(__VA_ARGS__)))
#define OVS_ACQ_AFTER(...) __attribute__((acquired_after(__VA_ARGS__)))
-#elif __CHECKER__
-/* "sparse" annotations for mutexes and mutex-like constructs.
- *
- * Change the thread-safety check annotations to use "context" attribute.
- *
- * OVS_MACRO_LOCK and OVS_MACRO_RELEASE are suitable for use within macros,
- * where there is no function prototype to annotate. */
-#define OVS_LOCKABLE
-#define OVS_REQ_RDLOCK(...) __attribute__((context(MUTEX, 1, 1)))
-#define OVS_ACQ_RDLOCK(...) __attribute__((context(MUTEX, 0, 1)))
-#define OVS_REQ_WRLOCK(...) __attribute__((context(MUTEX, 1, 1)))
-#define OVS_ACQ_WRLOCK(...) __attribute__((context(MUTEX, 0, 1)))
-#define OVS_REQUIRES(...) __attribute__((context(MUTEX, 1, 1)))
-#define OVS_ACQUIRES(...) __attribute__((context(MUTEX, 0, 1)))
-#define OVS_TRY_WRLOCK(RETVAL, ...)
-#define OVS_TRY_RDLOCK(RETVAL, ...)
-#define OVS_TRY_LOCK(REVAL, ...)
-#define OVS_GUARDED
-#define OVS_GUARDED_BY(...)
-#define OVS_EXCLUDED(...)
-#define OVS_RELEASES(...) __attribute__((context(MUTEX, 1, 0)))
-#define OVS_ACQ_BEFORE(...)
-#define OVS_ACQ_AFTER(...)
-#define OVS_MACRO_LOCK(...) __context__(MUTEX, 0, 1)
-#define OVS_MACRO_RELEASE(...) __context__(MUTEX, 1, 0)
-#else
+#define OVS_NO_THREAD_SAFETY_ANALYSIS \
+ __attribute__((no_thread_safety_analysis))
+#else /* not Clang */
#define OVS_LOCKABLE
#define OVS_REQ_RDLOCK(...)
#define OVS_ACQ_RDLOCK(...)
#define OVS_RELEASES(...)
#define OVS_ACQ_BEFORE(...)
#define OVS_ACQ_AFTER(...)
-#define OVS_MACRO_LOCK(...)
-#define OVS_MACRO_RELEASE(...)
+#define OVS_NO_THREAD_SAFETY_ANALYSIS
#endif
/* ISO C says that a C implementation may choose any integer type for an enum