lttng: BUILD_RUNTIME_BUG_ON

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/staging/lttng/lib/bug.h

+#ifndef _LTTNG_BUG_H
+#define _LTTNG_BUG_H
+
+/*
+ * lib/bug.h
+ *
+ * (C) Copyright 2010-2011 - Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+ *
+ * Dual LGPL v2.1/GPL v2 license.
+ */
+
+/**
+ * BUILD_RUNTIME_BUG_ON - check condition at build (if constant) or runtime
+ * @condition: the condition which should be false.
+ *
+ * If the condition is a constant and true, the compiler will generate a build
+ * error. If the condition is not constant, a BUG will be triggered at runtime
+ * if the condition is ever true. If the condition is constant and false, no
+ * code is emitted.
+ */
+#define BUILD_RUNTIME_BUG_ON(condition)				\
+	do {							\
+		if (__builtin_constant_p(condition))		\
+			BUILD_BUG_ON(condition);		\
+		else						\
+			BUG_ON(condition);			\
+	} while (0)
+
+#endif