compiler*.h: sync include/linux/compiler*.h with Linux 3.16

Copy them from Linux v3.16 tag.
My main motivation of this commit is to add compiler-clang.h.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
Cc: Jeroen Hofstee <jeroen@myspectrum.nl>

1 files changed, 41 insertions, 16 deletions

diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h
index 9896e54..02ae99e 100644
--- a/include/linux/compiler-gcc.h
+++ b/include/linux/compiler-gcc.h
@@ -5,6 +5,9 @@
 /*
  * Common definitions for all gcc versions go here.
  */
+#define GCC_VERSION (__GNUC__ * 10000 \
+		   + __GNUC_MINOR__ * 100 \
+		   + __GNUC_PATCHLEVEL__)
 
 
 /* Optimization barrier */
@@ -34,9 +37,15 @@
     __asm__ ("" : "=r"(__ptr) : "0"(ptr));		\
     (typeof(ptr)) (__ptr + (off)); })
 
+/* Make the optimizer believe the variable can be manipulated arbitrarily. */
+#define OPTIMIZER_HIDE_VAR(var) __asm__ ("" : "=r" (var) : "0" (var))
+
+#ifdef __CHECKER__
+#define __must_be_array(arr) 0
+#else
 /* &a[0] degrades to a pointer: a different type from an array */
-#define __must_be_array(a) \
-  BUILD_BUG_ON_ZERO(__builtin_types_compatible_p(typeof(a), typeof(&a[0])))
+#define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0]))
+#endif
 
 /*
  * Force always-inline if the user requests it so via the .config,
@@ -44,15 +53,18 @@
  */
 #if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \
     !defined(CONFIG_OPTIMIZE_INLINING) || (__GNUC__ < 4)
-# define inline		inline		__attribute__((always_inline))
-# define __inline__	__inline__	__attribute__((always_inline))
-# define __inline	__inline	__attribute__((always_inline))
+# define inline		inline		__attribute__((always_inline)) notrace
+# define __inline__	__inline__	__attribute__((always_inline)) notrace
+# define __inline	__inline	__attribute__((always_inline)) notrace
+#else
+/* A lot of inline functions can cause havoc with function tracing */
+# define inline		inline		notrace
+# define __inline__	__inline__	notrace
+# define __inline	__inline	notrace
 #endif
 
 #define __deprecated			__attribute__((deprecated))
-#ifndef __packed
-# define __packed			__attribute__((packed))
-#endif
+#define __packed			__attribute__((packed))
 #define __weak				__attribute__((weak))
 
 /*
@@ -60,8 +72,12 @@
  * naked functions because then mcount is called without stack and frame pointer
  * being set up and there is no chance to restore the lr register to the value
  * before mcount was called.
+ *
+ * The asm() bodies of naked functions often depend on standard calling conventions,
+ * therefore they must be noinline and noclone.  GCC 4.[56] currently fail to enforce
+ * this, so we must do so ourselves.  See GCC PR44290.
  */
-#define __naked				__attribute__((naked)) notrace
+#define __naked				__attribute__((naked)) noinline __noclone notrace
 
 #define __noreturn			__attribute__((noreturn))
 
@@ -75,13 +91,10 @@
  * would be.
  * [...]
  */
-#ifndef __pure
-# define __pure				__attribute__((pure))
-#endif
-#ifndef __aligned
-# define __aligned(x)			__attribute__((aligned(x)))
-#endif
-#define __printf(a,b)			__attribute__((format(printf,a,b)))
+#define __pure				__attribute__((pure))
+#define __aligned(x)			__attribute__((aligned(x)))
+#define __printf(a, b)			__attribute__((format(printf, a, b)))
+#define __scanf(a, b)			__attribute__((format(scanf, a, b)))
 #define  noinline			__attribute__((noinline))
 #define __attribute_const__		__attribute__((__const__))
 #define __maybe_unused			__attribute__((unused))
@@ -91,3 +104,15 @@
 #define _gcc_header(x) __gcc_header(linux/compiler-gcc##x.h)
 #define gcc_header(x) _gcc_header(x)
 #include gcc_header(__GNUC__)
+
+#if !defined(__noclone)
+#define __noclone	/* not needed */
+#endif
+
+/*
+ * A trick to suppress uninitialized variable warning without generating any
+ * code
+ */
+#define uninitialized_var(x) x = x
+
+#define __always_inline		inline __attribute__((always_inline))