diff options
Diffstat (limited to 'include/linux/compiler_types.h')
| -rw-r--r-- | include/linux/compiler_types.h | 267 |
1 files changed, 135 insertions, 132 deletions
diff --git a/include/linux/compiler_types.h b/include/linux/compiler_types.h index 6b79a9bba9a7..3525c179698c 100644 --- a/include/linux/compiler_types.h +++ b/include/linux/compiler_types.h @@ -54,32 +54,32 @@ extern void __chk_io_ptr(const volatile void __iomem *); #ifdef __KERNEL__ -#ifdef __GNUC__ +/* Compiler specific macros. */ +#ifdef __clang__ +#include <linux/compiler-clang.h> +#elif defined(__INTEL_COMPILER) +#include <linux/compiler-intel.h> +#elif defined(__GNUC__) +/* The above compilers also define __GNUC__, so order is important here. */ #include <linux/compiler-gcc.h> -#endif - -#if defined(CC_USING_HOTPATCH) && !defined(__CHECKER__) -#define notrace __attribute__((hotpatch(0,0))) #else -#define notrace __attribute__((no_instrument_function)) +#error "Unknown compiler" #endif -/* Intel compiler defines __GNUC__. So we will overwrite implementations - * coming from above header files here - */ -#ifdef __INTEL_COMPILER -# include <linux/compiler-intel.h> -#endif - -/* Clang compiler defines __GNUC__. So we will overwrite implementations - * coming from above header files here +/* + * Some architectures need to provide custom definitions of macros provided + * by linux/compiler-*.h, and can do so using asm/compiler.h. We include that + * conditionally rather than using an asm-generic wrapper in order to avoid + * build failures if any C compilation, which will include this file via an + * -include argument in c_flags, occurs prior to the asm-generic wrappers being + * generated. */ -#ifdef __clang__ -#include <linux/compiler-clang.h> +#ifdef CONFIG_HAVE_ARCH_COMPILER_H +#include <asm/compiler.h> #endif /* - * Generic compiler-dependent macros required for kernel + * Generic compiler-independent macros required for kernel * build go below this comment. Actual compiler/compiler version * specific implementations come from the above header files */ @@ -106,169 +106,172 @@ struct ftrace_likely_data { unsigned long constant; }; +/* Don't. Just don't. */ +#define __deprecated +#define __deprecated_for_modules + #endif /* __KERNEL__ */ #endif /* __ASSEMBLY__ */ -#ifdef __KERNEL__ /* - * Allow us to mark functions as 'deprecated' and have gcc emit a nice - * warning for each use, in hopes of speeding the functions removal. - * Usage is: - * int __deprecated foo(void) + * The below symbols may be defined for one or more, but not ALL, of the above + * compilers. We don't consider that to be an error, so set them to nothing. + * For example, some of them are for compiler specific plugins. */ -#ifndef __deprecated -# define __deprecated /* unimplemented */ -#endif - -#ifdef MODULE -#define __deprecated_for_modules __deprecated -#else -#define __deprecated_for_modules -#endif - -#ifndef __must_check -#define __must_check -#endif - -#ifndef CONFIG_ENABLE_MUST_CHECK -#undef __must_check -#define __must_check -#endif -#ifndef CONFIG_ENABLE_WARN_DEPRECATED -#undef __deprecated -#undef __deprecated_for_modules -#define __deprecated -#define __deprecated_for_modules +#ifndef __designated_init +# define __designated_init #endif -#ifndef __malloc -#define __malloc +#ifndef __latent_entropy +# define __latent_entropy #endif -/* - * Allow us to avoid 'defined but not used' warnings on functions and data, - * as well as force them to be emitted to the assembly file. - * - * As of gcc 3.4, static functions that are not marked with attribute((used)) - * may be elided from the assembly file. As of gcc 3.4, static data not so - * marked will not be elided, but this may change in a future gcc version. - * - * NOTE: Because distributions shipped with a backported unit-at-a-time - * compiler in gcc 3.3, we must define __used to be __attribute__((used)) - * for gcc >=3.3 instead of 3.4. - * - * In prior versions of gcc, such functions and data would be emitted, but - * would be warned about except with attribute((unused)). - * - * Mark functions that are referenced only in inline assembly as __used so - * the code is emitted even though it appears to be unreferenced. - */ -#ifndef __used -# define __used /* unimplemented */ +#ifndef __randomize_layout +# define __randomize_layout __designated_init #endif -#ifndef __maybe_unused -# define __maybe_unused /* unimplemented */ +#ifndef __no_randomize_layout +# define __no_randomize_layout #endif -#ifndef __always_unused -# define __always_unused /* unimplemented */ +#ifndef randomized_struct_fields_start +# define randomized_struct_fields_start +# define randomized_struct_fields_end #endif -#ifndef noinline -#define noinline +#ifndef __visible +#define __visible #endif /* - * Rather then using noinline to prevent stack consumption, use - * noinline_for_stack instead. For documentation reasons. + * Assume alignment of return value. */ -#define noinline_for_stack noinline - -#ifndef __always_inline -#define __always_inline inline +#ifndef __assume_aligned +#define __assume_aligned(a, ...) #endif -#endif /* __KERNEL__ */ +/* Are two types/vars the same type (ignoring qualifiers)? */ +#define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b)) + +/* Is this type a native word size -- useful for atomic operations */ +#define __native_word(t) \ + (sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || \ + sizeof(t) == sizeof(int) || sizeof(t) == sizeof(long)) -/* - * From the GCC manual: - * - * Many functions do not examine any values except their arguments, - * and have no effects except the return value. Basically this is - * just slightly more strict class than the `pure' attribute above, - * since function is not allowed to read global memory. - * - * Note that a function that has pointer arguments and examines the - * data pointed to must _not_ be declared `const'. Likewise, a - * function that calls a non-`const' function usually must not be - * `const'. It does not make sense for a `const' function to return - * `void'. - */ #ifndef __attribute_const__ -# define __attribute_const__ /* unimplemented */ +#define __attribute_const__ __attribute__((__const__)) #endif -#ifndef __designated_init -# define __designated_init +#ifndef __noclone +#define __noclone #endif -#ifndef __latent_entropy -# define __latent_entropy +/* Helpers for emitting diagnostics in pragmas. */ +#ifndef __diag +#define __diag(string) #endif -#ifndef __randomize_layout -# define __randomize_layout __designated_init +#ifndef __diag_GCC +#define __diag_GCC(version, severity, string) #endif -#ifndef __no_randomize_layout -# define __no_randomize_layout -#endif +#define __diag_push() __diag(push) +#define __diag_pop() __diag(pop) -#ifndef randomized_struct_fields_start -# define randomized_struct_fields_start -# define randomized_struct_fields_end -#endif +#define __diag_ignore(compiler, version, option, comment) \ + __diag_ ## compiler(version, ignore, option) +#define __diag_warn(compiler, version, option, comment) \ + __diag_ ## compiler(version, warn, option) +#define __diag_error(compiler, version, option, comment) \ + __diag_ ## compiler(version, error, option) /* - * Tell gcc if a function is cold. The compiler will assume any path - * directly leading to the call is unlikely. + * From the GCC manual: + * + * Many functions have no effects except the return value and their + * return value depends only on the parameters and/or global + * variables. Such a function can be subject to common subexpression + * elimination and loop optimization just as an arithmetic operator + * would be. + * [...] */ - -#ifndef __cold -#define __cold +#define __pure __attribute__((pure)) +#define __aligned(x) __attribute__((aligned(x))) +#define __aligned_largest __attribute__((aligned)) +#define __printf(a, b) __attribute__((format(printf, a, b))) +#define __scanf(a, b) __attribute__((format(scanf, a, b))) +#define __maybe_unused __attribute__((unused)) +#define __always_unused __attribute__((unused)) +#define __mode(x) __attribute__((mode(x))) +#define __malloc __attribute__((__malloc__)) +#define __used __attribute__((__used__)) +#define __noreturn __attribute__((noreturn)) +#define __packed __attribute__((packed)) +#define __weak __attribute__((weak)) +#define __alias(symbol) __attribute__((alias(#symbol))) +#define __cold __attribute__((cold)) +#define __section(S) __attribute__((__section__(#S))) + + +#ifdef CONFIG_ENABLE_MUST_CHECK +#define __must_check __attribute__((warn_unused_result)) +#else +#define __must_check #endif -/* Simple shorthand for a section definition */ -#ifndef __section -# define __section(S) __attribute__ ((__section__(#S))) +#if defined(CC_USING_HOTPATCH) && !defined(__CHECKER__) +#define notrace __attribute__((hotpatch(0, 0))) +#else +#define notrace __attribute__((no_instrument_function)) #endif -#ifndef __visible -#define __visible -#endif +#define __compiler_offsetof(a, b) __builtin_offsetof(a, b) -#ifndef __nostackprotector -# define __nostackprotector +/* + * 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 /* - * Assume alignment of return value. + * Force always-inline if the user requests it so via the .config. + * 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. */ -#ifndef __assume_aligned -#define __assume_aligned(a, ...) +#if !defined(CONFIG_ARCH_SUPPORTS_OPTIMIZED_INLINING) || \ + !defined(CONFIG_OPTIMIZE_INLINING) +#define inline \ + inline __attribute__((always_inline, unused)) notrace __gnu_inline +#else +#define inline inline __attribute__((unused)) notrace __gnu_inline #endif +#define __inline__ inline +#define __inline inline +#define noinline __attribute__((noinline)) -/* Are two types/vars the same type (ignoring qualifiers)? */ -#ifndef __same_type -# define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b)) +#ifndef __always_inline +#define __always_inline inline __attribute__((always_inline)) #endif -/* Is this type a native word size -- useful for atomic operations */ -#ifndef __native_word -# define __native_word(t) (sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || sizeof(t) == sizeof(int) || sizeof(t) == sizeof(long)) -#endif +/* + * Rather then using noinline to prevent stack consumption, use + * noinline_for_stack instead. For documentation reasons. + */ +#define noinline_for_stack noinline #endif /* __LINUX_COMPILER_TYPES_H */ |