Linux kernel mirror (for testing)
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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#define __compiletime_object_size(obj) __builtin_object_size(obj, 0)
45
46#if defined(LATENT_ENTROPY_PLUGIN) && !defined(__CHECKER__)
47#define __latent_entropy __attribute__((latent_entropy))
48#endif
49
50/*
51 * calling noreturn functions, __builtin_unreachable() and __builtin_trap()
52 * confuse the stack allocation in gcc, leading to overly large stack
53 * frames, see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82365
54 *
55 * Adding an empty inline assembly before it works around the problem
56 */
57#define barrier_before_unreachable() asm volatile("")
58
59/*
60 * Mark a position in code as unreachable. This can be used to
61 * suppress control flow warnings after asm blocks that transfer
62 * control elsewhere.
63 */
64#define unreachable() \
65 do { \
66 annotate_unreachable(); \
67 barrier_before_unreachable(); \
68 __builtin_unreachable(); \
69 } while (0)
70
71#if defined(RANDSTRUCT_PLUGIN) && !defined(__CHECKER__)
72#define __randomize_layout __attribute__((randomize_layout))
73#define __no_randomize_layout __attribute__((no_randomize_layout))
74/* This anon struct can add padding, so only enable it under randstruct. */
75#define randomized_struct_fields_start struct {
76#define randomized_struct_fields_end } __randomize_layout;
77#endif
78
79/*
80 * GCC 'asm goto' miscompiles certain code sequences:
81 *
82 * http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670
83 *
84 * Work it around via a compiler barrier quirk suggested by Jakub Jelinek.
85 *
86 * (asm goto is automatically volatile - the naming reflects this.)
87 */
88#define asm_volatile_goto(x...) do { asm goto(x); asm (""); } while (0)
89
90#if defined(CONFIG_ARCH_USE_BUILTIN_BSWAP)
91#define __HAVE_BUILTIN_BSWAP32__
92#define __HAVE_BUILTIN_BSWAP64__
93#define __HAVE_BUILTIN_BSWAP16__
94#endif /* CONFIG_ARCH_USE_BUILTIN_BSWAP */
95
96#if GCC_VERSION >= 70000
97#define KASAN_ABI_VERSION 5
98#else
99#define KASAN_ABI_VERSION 4
100#endif
101
102#if __has_attribute(__no_sanitize_address__)
103#define __no_sanitize_address __attribute__((no_sanitize_address))
104#else
105#define __no_sanitize_address
106#endif
107
108#if defined(__SANITIZE_THREAD__) && __has_attribute(__no_sanitize_thread__)
109#define __no_sanitize_thread __attribute__((no_sanitize_thread))
110#else
111#define __no_sanitize_thread
112#endif
113
114#if __has_attribute(__no_sanitize_undefined__)
115#define __no_sanitize_undefined __attribute__((no_sanitize_undefined))
116#else
117#define __no_sanitize_undefined
118#endif
119
120#if defined(CONFIG_KCOV) && __has_attribute(__no_sanitize_coverage__)
121#define __no_sanitize_coverage __attribute__((no_sanitize_coverage))
122#else
123#define __no_sanitize_coverage
124#endif
125
126/*
127 * Turn individual warnings and errors on and off locally, depending
128 * on version.
129 */
130#define __diag_GCC(version, severity, s) \
131 __diag_GCC_ ## version(__diag_GCC_ ## severity s)
132
133/* Severity used in pragma directives */
134#define __diag_GCC_ignore ignored
135#define __diag_GCC_warn warning
136#define __diag_GCC_error error
137
138#define __diag_str1(s) #s
139#define __diag_str(s) __diag_str1(s)
140#define __diag(s) _Pragma(__diag_str(GCC diagnostic s))
141
142#if GCC_VERSION >= 80000
143#define __diag_GCC_8(s) __diag(s)
144#else
145#define __diag_GCC_8(s)
146#endif