diff options
Diffstat (limited to 'include/linux/compiler-gcc.h')
| -rw-r--r-- | include/linux/compiler-gcc.h | 116 |
1 files changed, 40 insertions, 76 deletions
diff --git a/include/linux/compiler-gcc.h b/include/linux/compiler-gcc.h index fd282c7d3e5e..250b9b7cfd60 100644 --- a/include/linux/compiler-gcc.h +++ b/include/linux/compiler-gcc.h @@ -10,6 +10,10 @@ + __GNUC_MINOR__ * 100 \ + __GNUC_PATCHLEVEL__) +#if GCC_VERSION < 40600 +# error Sorry, your compiler is too old - please upgrade it. +#endif + /* Optimization barrier */ /* The "volatile" is due to gcc bugs */ @@ -58,6 +62,12 @@ #define OPTIMIZER_HIDE_VAR(var) \ __asm__ ("" : "=r" (var) : "0" (var)) +/* + * A trick to suppress uninitialized variable warning without generating any + * code + */ +#define uninitialized_var(x) x = x + #ifdef __CHECKER__ #define __must_be_array(a) 0 #else @@ -66,29 +76,43 @@ #endif /* + * Feature detection for gnu_inline (gnu89 extern inline semantics). Either + * __GNUC_STDC_INLINE__ is defined (not using gnu89 extern inline semantics, + * and we opt in to the gnu89 semantics), or __GNUC_STDC_INLINE__ is not + * defined so the gnu89 semantics are the default. + */ +#ifdef __GNUC_STDC_INLINE__ +# define __gnu_inline __attribute__((gnu_inline)) +#else +# define __gnu_inline +#endif + +/* * Force always-inline if the user requests it so via the .config, * or if gcc is too old. * GCC does not warn about unused static inline functions for * -Wunused-function. This turns out to avoid the need for complex #ifdef * directives. Suppress the warning in clang as well by using "unused" * function attribute, which is redundant but not harmful for gcc. + * Prefer gnu_inline, so that extern inline functions do not emit an + * externally visible function. This makes extern inline behave as per gnu89 + * semantics rather than c99. This prevents multiple symbol definition errors + * of extern inline functions at link time. + * A lot of inline functions can cause havoc with function tracing. */ #if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \ - !defined(CONFIG_OPTIMIZE_INLINING) || (__GNUC__ < 4) -#define inline inline __attribute__((always_inline,unused)) notrace -#define __inline__ __inline__ __attribute__((always_inline,unused)) notrace -#define __inline __inline __attribute__((always_inline,unused)) notrace + !defined(CONFIG_OPTIMIZE_INLINING) +#define inline \ + inline __attribute__((always_inline, unused)) notrace __gnu_inline #else -/* A lot of inline functions can cause havoc with function tracing */ -#define inline inline __attribute__((unused)) notrace -#define __inline__ __inline__ __attribute__((unused)) notrace -#define __inline __inline __attribute__((unused)) notrace +#define inline inline __attribute__((unused)) notrace __gnu_inline #endif +#define __inline__ inline +#define __inline inline #define __always_inline inline __attribute__((always_inline)) #define noinline __attribute__((noinline)) -#define __deprecated __attribute__((deprecated)) #define __packed __attribute__((packed)) #define __weak __attribute__((weak)) #define __alias(symbol) __attribute__((alias(#symbol))) @@ -133,47 +157,13 @@ #define __always_unused __attribute__((unused)) #define __mode(x) __attribute__((mode(x))) -/* gcc version specific checks */ - -#if GCC_VERSION < 30200 -# error Sorry, your compiler is too old - please upgrade it. -#endif - -#if GCC_VERSION < 30300 -# define __used __attribute__((__unused__)) -#else -# define __used __attribute__((__used__)) -#endif - -#ifdef CONFIG_GCOV_KERNEL -# if GCC_VERSION < 30400 -# error "GCOV profiling support for gcc versions below 3.4 not included" -# endif /* __GNUC_MINOR__ */ -#endif /* CONFIG_GCOV_KERNEL */ - -#if GCC_VERSION >= 30400 #define __must_check __attribute__((warn_unused_result)) #define __malloc __attribute__((__malloc__)) -#endif - -#if GCC_VERSION >= 40000 - -/* GCC 4.1.[01] miscompiles __weak */ -#ifdef __KERNEL__ -# if GCC_VERSION >= 40100 && GCC_VERSION <= 40101 -# error Your version of gcc miscompiles the __weak directive -# endif -#endif #define __used __attribute__((__used__)) #define __compiler_offsetof(a, b) \ __builtin_offsetof(a, b) -#if GCC_VERSION >= 40100 -# define __compiletime_object_size(obj) __builtin_object_size(obj, 0) -#endif - -#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 @@ -192,24 +182,19 @@ #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 */ -#if GCC_VERSION >= 40500 +#define __compiletime_object_size(obj) __builtin_object_size(obj, 0) #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 -#endif +#endif /* __CHECKER__ */ /* * calling noreturn functions, __builtin_unreachable() and __builtin_trap() @@ -247,10 +232,6 @@ #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 @@ -259,8 +240,7 @@ */ #define __visible __attribute__((externally_visible)) -#endif /* GCC_VERSION >= 40600 */ - +/* gcc version specific checks */ #if GCC_VERSION >= 40900 && !defined(__CHECKER__) /* @@ -294,10 +274,8 @@ * 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 @@ -326,10 +304,9 @@ * https://gcc.gnu.org/onlinedocs/gcc/Designated-Inits.html */ #define __designated_init __attribute__((designated_init)) +#define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1 #endif -#endif /* gcc version >= 40000 specific checks */ - #if !defined(__noclone) #define __noclone /* not needed */ #endif @@ -339,16 +316,6 @@ #endif /* - * A trick to suppress uninitialized variable warning without generating any - * code - */ -#define uninitialized_var(x) x = x - -#if GCC_VERSION >= 50100 -#define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1 -#endif - -/* * Turn individual warnings and errors on and off locally, depending * on version. */ @@ -360,12 +327,9 @@ #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) |