compiler.h: Move compiletime_assert() macros into compiler_types.h
authorWill Deacon <will@kernel.org>
Tue, 21 Jul 2020 08:54:15 +0000 (09:54 +0100)
committerWill Deacon <will@kernel.org>
Tue, 21 Jul 2020 09:50:37 +0000 (10:50 +0100)
The kernel test robot reports that moving READ_ONCE() out into its own
header breaks a W=1 build for parisc, which is relying on the definition
of compiletime_assert() being available:

  | In file included from ./arch/parisc/include/generated/asm/rwonce.h:1,
  |                  from ./include/asm-generic/barrier.h:16,
  |                  from ./arch/parisc/include/asm/barrier.h:29,
  |                  from ./arch/parisc/include/asm/atomic.h:11,
  |                  from ./include/linux/atomic.h:7,
  |                  from kernel/locking/percpu-rwsem.c:2:
  | ./arch/parisc/include/asm/atomic.h: In function 'atomic_read':
  | ./include/asm-generic/rwonce.h:36:2: error: implicit declaration of function 'compiletime_assert' [-Werror=implicit-function-declaration]
  |    36 |  compiletime_assert(__native_word(t) || sizeof(t) == sizeof(long long), \
  |       |  ^~~~~~~~~~~~~~~~~~
  | ./include/asm-generic/rwonce.h:49:2: note: in expansion of macro 'compiletime_assert_rwonce_type'
  |    49 |  compiletime_assert_rwonce_type(x);    \
  |       |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  | ./arch/parisc/include/asm/atomic.h:73:9: note: in expansion of macro 'READ_ONCE'
  |    73 |  return READ_ONCE((v)->counter);
  |       |         ^~~~~~~~~

Move these macros into compiler_types.h, so that they are available to
READ_ONCE() and friends.

Link: http://lists.infradead.org/pipermail/linux-arm-kernel/2020-July/587094.html
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Will Deacon <will@kernel.org>
include/linux/compiler.h
include/linux/compiler_types.h

index f075a3d..59f7194 100644 (file)
@@ -273,47 +273,6 @@ static inline void *offset_to_ptr(const int *off)
 
 #endif /* __ASSEMBLY__ */
 
-/* Compile time object size, -1 for unknown */
-#ifndef __compiletime_object_size
-# define __compiletime_object_size(obj) -1
-#endif
-#ifndef __compiletime_warning
-# define __compiletime_warning(message)
-#endif
-#ifndef __compiletime_error
-# define __compiletime_error(message)
-#endif
-
-#ifdef __OPTIMIZE__
-# define __compiletime_assert(condition, msg, prefix, suffix)          \
-       do {                                                            \
-               extern void prefix ## suffix(void) __compiletime_error(msg); \
-               if (!(condition))                                       \
-                       prefix ## suffix();                             \
-       } while (0)
-#else
-# define __compiletime_assert(condition, msg, prefix, suffix) do { } while (0)
-#endif
-
-#define _compiletime_assert(condition, msg, prefix, suffix) \
-       __compiletime_assert(condition, msg, prefix, suffix)
-
-/**
- * compiletime_assert - break build and emit msg if condition is false
- * @condition: a compile-time constant condition to check
- * @msg:       a message to emit if condition is false
- *
- * In tradition of POSIX assert, this macro will break the build if the
- * supplied condition is *false*, emitting the supplied error message if the
- * compiler has support to do so.
- */
-#define compiletime_assert(condition, msg) \
-       _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
-
-#define compiletime_assert_atomic_type(t)                              \
-       compiletime_assert(__native_word(t),                            \
-               "Need native word sized stores/loads for atomicity.")
-
 /* &a[0] degrades to a pointer: a different type from an array */
 #define __must_be_array(a)     BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0]))
 
index c3bf771..d9bbb62 100644 (file)
@@ -300,6 +300,47 @@ struct ftrace_likely_data {
        (sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || \
         sizeof(t) == sizeof(int) || sizeof(t) == sizeof(long))
 
+/* Compile time object size, -1 for unknown */
+#ifndef __compiletime_object_size
+# define __compiletime_object_size(obj) -1
+#endif
+#ifndef __compiletime_warning
+# define __compiletime_warning(message)
+#endif
+#ifndef __compiletime_error
+# define __compiletime_error(message)
+#endif
+
+#ifdef __OPTIMIZE__
+# define __compiletime_assert(condition, msg, prefix, suffix)          \
+       do {                                                            \
+               extern void prefix ## suffix(void) __compiletime_error(msg); \
+               if (!(condition))                                       \
+                       prefix ## suffix();                             \
+       } while (0)
+#else
+# define __compiletime_assert(condition, msg, prefix, suffix) do { } while (0)
+#endif
+
+#define _compiletime_assert(condition, msg, prefix, suffix) \
+       __compiletime_assert(condition, msg, prefix, suffix)
+
+/**
+ * compiletime_assert - break build and emit msg if condition is false
+ * @condition: a compile-time constant condition to check
+ * @msg:       a message to emit if condition is false
+ *
+ * In tradition of POSIX assert, this macro will break the build if the
+ * supplied condition is *false*, emitting the supplied error message if the
+ * compiler has support to do so.
+ */
+#define compiletime_assert(condition, msg) \
+       _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
+
+#define compiletime_assert_atomic_type(t)                              \
+       compiletime_assert(__native_word(t),                            \
+               "Need native word sized stores/loads for atomicity.")
+
 /* Helpers for emitting diagnostics in pragmas. */
 #ifndef __diag
 #define __diag(string)