관리-도구

편집 파일: compiler-gcc.h

/* SPDX-License-Identifier: GPL-2.0 */ #ifndef __LINUX_COMPILER_TYPES_H #error "Please don't include <linux/compiler-gcc.h> directly, include <linux/compiler.h> instead." #endif /* * Common definitions for all gcc versions go here. */ #define GCC_VERSION (__GNUC__ * 10000 \ + __GNUC_MINOR__ * 100 \ + __GNUC_PATCHLEVEL__) /* * This macro obfuscates arithmetic on a variable address so that gcc * shouldn't recognize the original var, and make assumptions about it. * * This is needed because the C standard makes it undefined to do * pointer arithmetic on "objects" outside their boundaries and the * gcc optimizers assume this is the case. In particular they * assume such arithmetic does not wrap. * * A miscompilation has been observed because of this on PPC. * To work around it we hide the relationship of the pointer and the object * using this macro. * * Versions of the ppc64 compiler before 4.1 had a bug where use of * RELOC_HIDE could trash r30. The bug can be worked around by changing * the inline assembly constraint from =g to =r, in this particular * case either is valid. */ #define RELOC_HIDE(ptr, off) \ ({ \ unsigned long __ptr; \ __asm__ ("" : "=r"(__ptr) : "0"(ptr)); \ (typeof(ptr)) (__ptr + (off)); \ }) #ifdef CONFIG_RETPOLINE #define __noretpoline __attribute__((__indirect_branch__("keep"))) #endif #define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__) #define __compiletime_object_size(obj) __builtin_object_size(obj, 0) #define __compiletime_warning(message) __attribute__((__warning__(message))) #define __compiletime_error(message) __attribute__((__error__(message))) #if defined(LATENT_ENTROPY_PLUGIN) && !defined(__CHECKER__) #define __latent_entropy __attribute__((latent_entropy)) #endif /* * calling noreturn functions, __builtin_unreachable() and __builtin_trap() * confuse the stack allocation in gcc, leading to overly large stack * frames, see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82365 * * Adding an empty inline assembly before it works around the problem */ #define barrier_before_unreachable() asm volatile("") /* * Mark a position in code as unreachable. This can be used to * suppress control flow warnings after asm blocks that transfer * control elsewhere. */ #define unreachable() \ do { \ annotate_unreachable(); \ barrier_before_unreachable(); \ __builtin_unreachable(); \ } while (0) #if defined(RANDSTRUCT_PLUGIN) && !defined(__CHECKER__) #define __randomize_layout __attribute__((randomize_layout)) #define __no_randomize_layout __attribute__((no_randomize_layout)) /* This anon struct can add padding, so only enable it under randstruct. */ #define randomized_struct_fields_start struct { #define randomized_struct_fields_end } __randomize_layout; #endif /* * GCC 'asm goto' miscompiles certain code sequences: * * http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670 * * Work it around via a compiler barrier quirk suggested by Jakub Jelinek. * * (asm goto is automatically volatile - the naming reflects this.) */ #define asm_volatile_goto(x...) do { asm goto(x); asm (""); } while (0) #if defined(CONFIG_ARCH_USE_BUILTIN_BSWAP) #define __HAVE_BUILTIN_BSWAP32__ #define __HAVE_BUILTIN_BSWAP64__ #define __HAVE_BUILTIN_BSWAP16__ #endif /* CONFIG_ARCH_USE_BUILTIN_BSWAP */ #if GCC_VERSION >= 70000 #define KASAN_ABI_VERSION 5 #elif GCC_VERSION >= 50000 #define KASAN_ABI_VERSION 4 #elif GCC_VERSION >= 40902 #define KASAN_ABI_VERSION 3 #endif #if __has_attribute(__no_sanitize_address__) #define __no_sanitize_address __attribute__((no_sanitize_address)) #else #define __no_sanitize_address #endif #if defined(__SANITIZE_THREAD__) && __has_attribute(__no_sanitize_thread__) #define __no_sanitize_thread __attribute__((no_sanitize_thread)) #else #define __no_sanitize_thread #endif #if __has_attribute(__no_sanitize_undefined__) #define __no_sanitize_undefined __attribute__((no_sanitize_undefined)) #else #define __no_sanitize_undefined #endif #if defined(CONFIG_KCOV) && __has_attribute(__no_sanitize_coverage__) #define __no_sanitize_coverage __attribute__((no_sanitize_coverage)) #else #define __no_sanitize_coverage #endif #if GCC_VERSION >= 50100 #define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1 #endif /* * GCC does not support KMSAN. */ #define __no_sanitize_memory #define __no_kmsan_checks /* * Turn individual warnings and errors on and off locally, depending * on version. */ #define __diag_GCC(version, severity, s) \ __diag_GCC_ ## version(__diag_GCC_ ## severity s) /* Severity used in pragma directives */ #define __diag_GCC_ignore ignored #define __diag_GCC_warn warning #define __diag_GCC_error error #define __diag_str1(s) #s #define __diag_str(s) __diag_str1(s) #define __diag(s) _Pragma(__diag_str(GCC diagnostic s)) #if GCC_VERSION >= 80000 #define __diag_GCC_8(s) __diag(s) #else #define __diag_GCC_8(s) #endif #define __diag_ignore_all(option, comment) \ __diag_GCC(8, ignore, option) /* * Prior to 9.1, -Wno-alloc-size-larger-than (and therefore the "alloc_size" * attribute) do not work, and must be disabled. */ #if GCC_VERSION < 90100 #undef __alloc_size__ #endif