Linux kernel mirror (for testing)
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linux
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/*
70 * GCC 'asm goto' miscompiles certain code sequences:
71 *
72 * http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670
73 *
74 * Work it around via a compiler barrier quirk suggested by Jakub Jelinek.
75 *
76 * (asm goto is automatically volatile - the naming reflects this.)
77 */
78#define asm_volatile_goto(x...) do { asm goto(x); asm (""); } while (0)
79
80#if defined(CONFIG_ARCH_USE_BUILTIN_BSWAP)
81#define __HAVE_BUILTIN_BSWAP32__
82#define __HAVE_BUILTIN_BSWAP64__
83#define __HAVE_BUILTIN_BSWAP16__
84#endif /* CONFIG_ARCH_USE_BUILTIN_BSWAP */
85
86#if GCC_VERSION >= 70000
87#define KASAN_ABI_VERSION 5
88#else
89#define KASAN_ABI_VERSION 4
90#endif
91
92#ifdef CONFIG_SHADOW_CALL_STACK
93#define __noscs __attribute__((__no_sanitize__("shadow-call-stack")))
94#endif
95
96#if __has_attribute(__no_sanitize_address__)
97#define __no_sanitize_address __attribute__((no_sanitize_address))
98#else
99#define __no_sanitize_address
100#endif
101
102#if defined(__SANITIZE_THREAD__) && __has_attribute(__no_sanitize_thread__)
103#define __no_sanitize_thread __attribute__((no_sanitize_thread))
104#else
105#define __no_sanitize_thread
106#endif
107
108#if __has_attribute(__no_sanitize_undefined__)
109#define __no_sanitize_undefined __attribute__((no_sanitize_undefined))
110#else
111#define __no_sanitize_undefined
112#endif
113
114#if defined(CONFIG_KCOV) && __has_attribute(__no_sanitize_coverage__)
115#define __no_sanitize_coverage __attribute__((no_sanitize_coverage))
116#else
117#define __no_sanitize_coverage
118#endif
119
120/*
121 * Treat __SANITIZE_HWADDRESS__ the same as __SANITIZE_ADDRESS__ in the kernel,
122 * matching the defines used by Clang.
123 */
124#ifdef __SANITIZE_HWADDRESS__
125#define __SANITIZE_ADDRESS__
126#endif
127
128/*
129 * Turn individual warnings and errors on and off locally, depending
130 * on version.
131 */
132#define __diag_GCC(version, severity, s) \
133 __diag_GCC_ ## version(__diag_GCC_ ## severity s)
134
135/* Severity used in pragma directives */
136#define __diag_GCC_ignore ignored
137#define __diag_GCC_warn warning
138#define __diag_GCC_error error
139
140#define __diag_str1(s) #s
141#define __diag_str(s) __diag_str1(s)
142#define __diag(s) _Pragma(__diag_str(GCC diagnostic s))
143
144#if GCC_VERSION >= 80000
145#define __diag_GCC_8(s) __diag(s)
146#else
147#define __diag_GCC_8(s)
148#endif
149
150#define __diag_ignore_all(option, comment) \
151 __diag_GCC(8, ignore, option)
152
153/*
154 * Prior to 9.1, -Wno-alloc-size-larger-than (and therefore the "alloc_size"
155 * attribute) do not work, and must be disabled.
156 */
157#if GCC_VERSION < 90100
158#undef __alloc_size__
159#endif