bug.h, compiler.h: introduce compiletime_assert & BUILD_BUG_ON_MSG
[~shefty/rdma-dev.git] / include / linux / bug.h
index dc11dc762fc34e55367bbec155f0c2ce2ef3a0cf..7f4818673c41f80d391faee5ea1667435d7bbf84 100644 (file)
@@ -17,6 +17,7 @@ struct pt_regs;
 #define BUILD_BUG_ON_ZERO(e) (0)
 #define BUILD_BUG_ON_NULL(e) ((void*)0)
 #define BUILD_BUG_ON_INVALID(e) (0)
+#define BUILD_BUG_ON_MSG(cond, msg) (0)
 #define BUILD_BUG_ON(condition) (0)
 #define BUILD_BUG() (0)
 #else /* __CHECKER__ */
@@ -39,6 +40,15 @@ struct pt_regs;
  */
 #define BUILD_BUG_ON_INVALID(e) ((void)(sizeof((__force long)(e))))
 
+/**
+ * BUILD_BUG_ON_MSG - break compile if a condition is true & emit supplied
+ *                   error message.
+ * @condition: the condition which the compiler should know is false.
+ *
+ * See BUILD_BUG_ON for description.
+ */
+#define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg)
+
 /**
  * BUILD_BUG_ON - break compile if a condition is true.
  * @condition: the condition which the compiler should know is false.
@@ -60,15 +70,8 @@ struct pt_regs;
 #ifndef __OPTIMIZE__
 #define BUILD_BUG_ON(condition) ((void)sizeof(char[1 - 2*!!(condition)]))
 #else
-#define BUILD_BUG_ON(condition)                                                \
-       do {                                                            \
-               bool __cond = !!(condition);                            \
-               extern void __build_bug_on_failed(void)                 \
-                       __compiletime_error("BUILD_BUG_ON failed");     \
-               if (__cond)                                             \
-                       __build_bug_on_failed();                        \
-               __compiletime_error_fallback(__cond);                   \
-       } while (0)
+#define BUILD_BUG_ON(condition) \
+       BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition)
 #endif
 
 /**
@@ -78,12 +81,7 @@ struct pt_regs;
  * build time, you should use BUILD_BUG to detect if it is
  * unexpectedly used.
  */
-#define BUILD_BUG()                                            \
-       do {                                                    \
-               extern void __build_bug_failed(void)            \
-                       __compiletime_error("BUILD_BUG failed");\
-               __build_bug_failed();                           \
-       } while (0)
+#define BUILD_BUG() BUILD_BUG_ON_MSG(1, "BUILD_BUG failed")
 
 #endif /* __CHECKER__ */