Messages in this thread Patch in this message | | | From | Masahiro Yamada <> | Subject | [PATCH] compiler-gcc: get back Clang build | Date | Tue, 21 Aug 2018 15:48:08 +0900 |
| |
Commit cafa0010cd51 ("Raise the minimum required gcc version to 4.6") missed the fact that <linux/compiler-gcc.h> is included by Clang as well as by GCC.
Clang actually defines __GNUC__, __GNUC_MINOR__, __GNUC_PATCHLEVEL__ and it looks like GCC 4.2.1.
$ scripts/gcc-version.sh -p clang 040201
If you try to build the kernel with Clang, you will get the "Sorry, your compiler is too old - please upgrade it." followed by a bunch of "unknown attribute" warnings.
Add !defined(__clang__) to the minimum version check.
Also, revive the version test blocks for versions >= 4.2.1 in order to disable features not supported by Clang.
Fixes: cafa0010cd51 ("Raise the minimum required gcc version to 4.6") Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com> ---
include/linux/compiler-gcc.h | 34 ++++++++++++++++++++++++++++------ 1 file changed, 28 insertions(+), 6 deletions(-)
diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h index 250b9b7..8e41fd2 100644 --- a/include/linux/compiler-gcc.h +++ b/include/linux/compiler-gcc.h @@ -10,7 +10,7 @@ + __GNUC_MINOR__ * 100 \ + __GNUC_PATCHLEVEL__) -#if GCC_VERSION < 40600 +#if !defined(__clang__) && GCC_VERSION < 40600 # error Sorry, your compiler is too old - please upgrade it. #endif @@ -163,7 +163,16 @@ #define __used __attribute__((__used__)) #define __compiler_offsetof(a, b) \ __builtin_offsetof(a, b) +#define __compiletime_object_size(obj) __builtin_object_size(obj, 0) +/* + * GCC version specific checks + * + * Keep the version checks for 4.2.1 or newer + * because Clang defines GCC_VERSION as 40201 + */ + +#if GCC_VERSION >= 40300 /* Mark functions as cold. gcc will assume any path leading to a call * to them will be unlikely. This means a lot of manual unlikely()s * are unnecessary now for any paths leading to the usual suspects @@ -182,15 +191,20 @@ #define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__) +#ifndef __CHECKER__ +# define __compiletime_warning(message) __attribute__((warning(message))) +# define __compiletime_error(message) __attribute__((error(message))) +#endif /* __CHECKER__ */ +#endif /* GCC_VERSION >= 40300 */ + +#if GCC_VERSION >= 40400 #define __optimize(level) __attribute__((__optimize__(level))) #define __nostackprotector __optimize("no-stack-protector") +#endif /* GCC_VERSION >= 40400 */ -#define __compiletime_object_size(obj) __builtin_object_size(obj, 0) +#if GCC_VERSION >= 40500 #ifndef __CHECKER__ -#define __compiletime_warning(message) __attribute__((warning(message))) -#define __compiletime_error(message) __attribute__((error(message))) - #ifdef LATENT_ENTROPY_PLUGIN #define __latent_entropy __attribute__((latent_entropy)) #endif @@ -232,6 +246,9 @@ #define randomized_struct_fields_end } __randomize_layout; #endif +#endif /* GCC_VERSION >= 40500 */ + +#if GCC_VERSION >= 40600 /* * When used with Link Time Optimization, gcc can optimize away C functions or * variables which are referenced only from assembly code. __visible tells the @@ -240,7 +257,7 @@ */ #define __visible __attribute__((externally_visible)) -/* gcc version specific checks */ +#endif /* GCC_VERSION >= 40600 */ #if GCC_VERSION >= 40900 && !defined(__CHECKER__) /* @@ -274,8 +291,10 @@ * folding in __builtin_bswap*() (yet), so don't set these for it. */ #if defined(CONFIG_ARCH_USE_BUILTIN_BSWAP) && !defined(__CHECKER__) +#if GCC_VERSION >= 40400 #define __HAVE_BUILTIN_BSWAP32__ #define __HAVE_BUILTIN_BSWAP64__ +#endif #if GCC_VERSION >= 40800 #define __HAVE_BUILTIN_BSWAP16__ #endif @@ -327,9 +346,12 @@ #define __diag_GCC_warn warning #define __diag_GCC_error error +/* Compilers before gcc-4.6 do not understand "#pragma GCC diagnostic push" */ +#if GCC_VERSION >= 40600 #define __diag_str1(s) #s #define __diag_str(s) __diag_str1(s) #define __diag(s) _Pragma(__diag_str(GCC diagnostic s)) +#endif #if GCC_VERSION >= 80000 #define __diag_GCC_8(s) __diag(s) -- 2.7.4
| |