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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef __LINUX_COMPILER_TYPES_H3#error "Please don't include <linux/compiler-gcc.h> directly, include <linux/compiler.h> instead."4#endif5 6/*7 * Common definitions for all gcc versions go here.8 */9#define GCC_VERSION (__GNUC__ * 10000 \10 + __GNUC_MINOR__ * 100 \11 + __GNUC_PATCHLEVEL__)12 13/*14 * This macro obfuscates arithmetic on a variable address so that gcc15 * shouldn't recognize the original var, and make assumptions about it.16 *17 * This is needed because the C standard makes it undefined to do18 * pointer arithmetic on "objects" outside their boundaries and the19 * gcc optimizers assume this is the case. In particular they20 * assume such arithmetic does not wrap.21 *22 * A miscompilation has been observed because of this on PPC.23 * To work around it we hide the relationship of the pointer and the object24 * using this macro.25 *26 * Versions of the ppc64 compiler before 4.1 had a bug where use of27 * RELOC_HIDE could trash r30. The bug can be worked around by changing28 * the inline assembly constraint from =g to =r, in this particular29 * case either is valid.30 */31#define RELOC_HIDE(ptr, off) \32({ \33 unsigned long __ptr; \34 __asm__ ("" : "=r"(__ptr) : "0"(ptr)); \35 (typeof(ptr)) (__ptr + (off)); \36})37 38#ifdef CONFIG_MITIGATION_RETPOLINE39#define __noretpoline __attribute__((__indirect_branch__("keep")))40#endif41 42#if defined(LATENT_ENTROPY_PLUGIN) && !defined(__CHECKER__)43#define __latent_entropy __attribute__((latent_entropy))44#endif45 46/*47 * calling noreturn functions, __builtin_unreachable() and __builtin_trap()48 * confuse the stack allocation in gcc, leading to overly large stack49 * frames, see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=8236550 *51 * Adding an empty inline assembly before it works around the problem52 */53#define barrier_before_unreachable() asm volatile("")54 55/*56 * Mark a position in code as unreachable. This can be used to57 * suppress control flow warnings after asm blocks that transfer58 * control elsewhere.59 */60#define unreachable() \61 do { \62 annotate_unreachable(); \63 barrier_before_unreachable(); \64 __builtin_unreachable(); \65 } while (0)66 67#if defined(CONFIG_ARCH_USE_BUILTIN_BSWAP)68#define __HAVE_BUILTIN_BSWAP32__69#define __HAVE_BUILTIN_BSWAP64__70#define __HAVE_BUILTIN_BSWAP16__71#endif /* CONFIG_ARCH_USE_BUILTIN_BSWAP */72 73#if GCC_VERSION >= 7000074#define KASAN_ABI_VERSION 575#else76#define KASAN_ABI_VERSION 477#endif78 79#ifdef CONFIG_SHADOW_CALL_STACK80#define __noscs __attribute__((__no_sanitize__("shadow-call-stack")))81#endif82 83#ifdef __SANITIZE_HWADDRESS__84#define __no_sanitize_address __attribute__((__no_sanitize__("hwaddress")))85#else86#define __no_sanitize_address __attribute__((__no_sanitize_address__))87#endif88 89#if defined(__SANITIZE_THREAD__)90#define __no_sanitize_thread __attribute__((__no_sanitize_thread__))91#else92#define __no_sanitize_thread93#endif94 95#define __no_sanitize_undefined __attribute__((__no_sanitize_undefined__))96 97/*98 * Only supported since gcc >= 1299 */100#if defined(CONFIG_KCOV) && __has_attribute(__no_sanitize_coverage__)101#define __no_sanitize_coverage __attribute__((__no_sanitize_coverage__))102#else103#define __no_sanitize_coverage104#endif105 106/*107 * Treat __SANITIZE_HWADDRESS__ the same as __SANITIZE_ADDRESS__ in the kernel,108 * matching the defines used by Clang.109 */110#ifdef __SANITIZE_HWADDRESS__111#define __SANITIZE_ADDRESS__112#endif113 114/*115 * GCC does not support KMSAN.116 */117#define __no_sanitize_memory118#define __no_kmsan_checks119 120/*121 * Turn individual warnings and errors on and off locally, depending122 * on version.123 */124#define __diag_GCC(version, severity, s) \125 __diag_GCC_ ## version(__diag_GCC_ ## severity s)126 127/* Severity used in pragma directives */128#define __diag_GCC_ignore ignored129#define __diag_GCC_warn warning130#define __diag_GCC_error error131 132#define __diag_str1(s) #s133#define __diag_str(s) __diag_str1(s)134#define __diag(s) _Pragma(__diag_str(GCC diagnostic s))135 136#if GCC_VERSION >= 80000137#define __diag_GCC_8(s) __diag(s)138#else139#define __diag_GCC_8(s)140#endif141 142#define __diag_ignore_all(option, comment) \143 __diag(__diag_GCC_ignore option)144 145/*146 * Prior to 9.1, -Wno-alloc-size-larger-than (and therefore the "alloc_size"147 * attribute) do not work, and must be disabled.148 */149#if GCC_VERSION < 90100150#undef __alloc_size__151#endif152