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1/* SPDX-License-Identifier: GPL-2.0 */ 2#ifndef __LINUX_COMPILER_TYPES_H 3#error "Please don't include <linux/compiler-gcc.h> directly, include <linux/compiler.h> instead." 4#endif 5 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 gcc 15 * shouldn't recognize the original var, and make assumptions about it. 16 * 17 * This is needed because the C standard makes it undefined to do 18 * pointer arithmetic on "objects" outside their boundaries and the 19 * gcc optimizers assume this is the case. In particular they 20 * 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 object 24 * using this macro. 25 * 26 * Versions of the ppc64 compiler before 4.1 had a bug where use of 27 * RELOC_HIDE could trash r30. The bug can be worked around by changing 28 * the inline assembly constraint from =g to =r, in this particular 29 * 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_RETPOLINE 39#define __noretpoline __attribute__((__indirect_branch__("keep"))) 40#endif 41 42#define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__) 43 44#if defined(LATENT_ENTROPY_PLUGIN) && !defined(__CHECKER__) 45#define __latent_entropy __attribute__((latent_entropy)) 46#endif 47 48/* 49 * calling noreturn functions, __builtin_unreachable() and __builtin_trap() 50 * confuse the stack allocation in gcc, leading to overly large stack 51 * frames, see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82365 52 * 53 * Adding an empty inline assembly before it works around the problem 54 */ 55#define barrier_before_unreachable() asm volatile("") 56 57/* 58 * Mark a position in code as unreachable. This can be used to 59 * suppress control flow warnings after asm blocks that transfer 60 * control elsewhere. 61 */ 62#define unreachable() \ 63 do { \ 64 annotate_unreachable(); \ 65 barrier_before_unreachable(); \ 66 __builtin_unreachable(); \ 67 } while (0) 68 69#if defined(CONFIG_ARCH_USE_BUILTIN_BSWAP) 70#define __HAVE_BUILTIN_BSWAP32__ 71#define __HAVE_BUILTIN_BSWAP64__ 72#define __HAVE_BUILTIN_BSWAP16__ 73#endif /* CONFIG_ARCH_USE_BUILTIN_BSWAP */ 74 75#if GCC_VERSION >= 70000 76#define KASAN_ABI_VERSION 5 77#else 78#define KASAN_ABI_VERSION 4 79#endif 80 81#ifdef CONFIG_SHADOW_CALL_STACK 82#define __noscs __attribute__((__no_sanitize__("shadow-call-stack"))) 83#endif 84 85#define __no_sanitize_address __attribute__((__no_sanitize_address__)) 86 87#if defined(__SANITIZE_THREAD__) 88#define __no_sanitize_thread __attribute__((__no_sanitize_thread__)) 89#else 90#define __no_sanitize_thread 91#endif 92 93#define __no_sanitize_undefined __attribute__((__no_sanitize_undefined__)) 94 95/* 96 * Only supported since gcc >= 12 97 */ 98#if defined(CONFIG_KCOV) && __has_attribute(__no_sanitize_coverage__) 99#define __no_sanitize_coverage __attribute__((__no_sanitize_coverage__)) 100#else 101#define __no_sanitize_coverage 102#endif 103 104/* 105 * Treat __SANITIZE_HWADDRESS__ the same as __SANITIZE_ADDRESS__ in the kernel, 106 * matching the defines used by Clang. 107 */ 108#ifdef __SANITIZE_HWADDRESS__ 109#define __SANITIZE_ADDRESS__ 110#endif 111 112/* 113 * GCC does not support KMSAN. 114 */ 115#define __no_sanitize_memory 116#define __no_kmsan_checks 117 118/* 119 * Turn individual warnings and errors on and off locally, depending 120 * on version. 121 */ 122#define __diag_GCC(version, severity, s) \ 123 __diag_GCC_ ## version(__diag_GCC_ ## severity s) 124 125/* Severity used in pragma directives */ 126#define __diag_GCC_ignore ignored 127#define __diag_GCC_warn warning 128#define __diag_GCC_error error 129 130#define __diag_str1(s) #s 131#define __diag_str(s) __diag_str1(s) 132#define __diag(s) _Pragma(__diag_str(GCC diagnostic s)) 133 134#if GCC_VERSION >= 80000 135#define __diag_GCC_8(s) __diag(s) 136#else 137#define __diag_GCC_8(s) 138#endif 139 140#define __diag_ignore_all(option, comment) \ 141 __diag_GCC(8, ignore, option) 142 143/* 144 * Prior to 9.1, -Wno-alloc-size-larger-than (and therefore the "alloc_size" 145 * attribute) do not work, and must be disabled. 146 */ 147#if GCC_VERSION < 90100 148#undef __alloc_size__ 149#endif