From: Miguel Ojeda Subject: [PATCH v5 04/15] Compiler Attributes: homogenize __must_be_array Date: Thu, 20 Sep 2018 19:22:50 +0200 Message-ID: <20180920172301.21868-5-miguel.ojeda.sandonis@gmail.com> References: <20180920172301.21868-1-miguel.ojeda.sandonis@gmail.com> Cc: linux-kernel@vger.kernel.org, Miguel Ojeda , Andreas Dilger , Masahiro Yamada , Michal Marek , Steven Rostedt , Mauro Carvalho Chehab , Olof Johansson , Konstantin Ryabitsev , "David S . Miller" , Andrey Ryabinin , Kees Cook , Thomas Gleixner , Ingo Molnar , Paul Lawrence , Sandipan Das , Andrey Konovalov , David Woodhouse , Will Deac To: Greg Kroah-Hartman Return-path: In-Reply-To: <20180920172301.21868-1-miguel.ojeda.sandonis@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org Different definitions of __must_be_array: * gcc: disabled for __CHECKER__ * clang: same definition as gcc's, but without __CHECKER__ * intel: the comment claims __builtin_types_compatible_p() is unsupported; but icc seems to support it since 13.0.1 (released in 2012). See https://godbolt.org/z/S0l6QQ Therefore, we can remove all of them and have a single definition in compiler.h Reviewed-by: Nick Desaulniers Reviewed-by: Luc Van Oostenryck Signed-off-by: Miguel Ojeda --- include/linux/compiler-clang.h | 1 - include/linux/compiler-gcc.h | 7 ------- include/linux/compiler-intel.h | 3 --- include/linux/compiler.h | 7 +++++++ 4 files changed, 7 insertions(+), 11 deletions(-) diff --git a/include/linux/compiler-clang.h b/include/linux/compiler-clang.h index d11cad61ba5c..fa9532f8d885 100644 --- a/include/linux/compiler-clang.h +++ b/include/linux/compiler-clang.h @@ -41,6 +41,5 @@ * compilers, like ICC. */ #define barrier() __asm__ __volatile__("" : : : "memory") -#define __must_be_array(a) BUILD_BUG_ON_ZERO(__same_type((a), &(a)[0])) #define __assume_aligned(a, ...) \ __attribute__((__assume_aligned__(a, ## __VA_ARGS__))) diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h index 7a1de7683df5..3b32bbfa5a49 100644 --- a/include/linux/compiler-gcc.h +++ b/include/linux/compiler-gcc.h @@ -68,13 +68,6 @@ */ #define uninitialized_var(x) x = x -#ifdef __CHECKER__ -#define __must_be_array(a) 0 -#else -/* &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])) -#endif - #ifdef RETPOLINE #define __noretpoline __attribute__((__indirect_branch__("keep"))) #endif diff --git a/include/linux/compiler-intel.h b/include/linux/compiler-intel.h index fef8bb3e53ef..6004b4588bd4 100644 --- a/include/linux/compiler-intel.h +++ b/include/linux/compiler-intel.h @@ -29,9 +29,6 @@ */ #define OPTIMIZER_HIDE_VAR(var) barrier() -/* Intel ECC compiler doesn't support __builtin_types_compatible_p() */ -#define __must_be_array(a) 0 - #endif /* icc has this, but it's called _bswap16 */ diff --git a/include/linux/compiler.h b/include/linux/compiler.h index ec4a28bad2c6..165b1d5683ed 100644 --- a/include/linux/compiler.h +++ b/include/linux/compiler.h @@ -357,4 +357,11 @@ static inline void *offset_to_ptr(const int *off) compiletime_assert(__native_word(t), \ "Need native word sized stores/loads for atomicity.") +#ifdef __CHECKER__ +#define __must_be_array(a) 0 +#else +/* &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])) +#endif + #endif /* __LINUX_COMPILER_H */ -- 2.17.1