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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/* https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58145 */
14#if GCC_VERSION < 40900
15# error Sorry, your version of GCC is too old - please use 4.9 or newer.
16#elif defined(CONFIG_ARM64) && GCC_VERSION < 50100
17/*
18 * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=63293
19 * https://lore.kernel.org/r/20210107111841.GN1551@shell.armlinux.org.uk
20 */
21# error Sorry, your version of GCC is too old - please use 5.1 or newer.
22#endif
23
24/*
25 * This macro obfuscates arithmetic on a variable address so that gcc
26 * shouldn't recognize the original var, and make assumptions about it.
27 *
28 * This is needed because the C standard makes it undefined to do
29 * pointer arithmetic on "objects" outside their boundaries and the
30 * gcc optimizers assume this is the case. In particular they
31 * assume such arithmetic does not wrap.
32 *
33 * A miscompilation has been observed because of this on PPC.
34 * To work around it we hide the relationship of the pointer and the object
35 * using this macro.
36 *
37 * Versions of the ppc64 compiler before 4.1 had a bug where use of
38 * RELOC_HIDE could trash r30. The bug can be worked around by changing
39 * the inline assembly constraint from =g to =r, in this particular
40 * case either is valid.
41 */
42#define RELOC_HIDE(ptr, off) \
43({ \
44 unsigned long __ptr; \
45 __asm__ ("" : "=r"(__ptr) : "0"(ptr)); \
46 (typeof(ptr)) (__ptr + (off)); \
47})
48
49#ifdef CONFIG_RETPOLINE
50#define __noretpoline __attribute__((__indirect_branch__("keep")))
51#endif
52
53#define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__)
54
55#define __compiletime_object_size(obj) __builtin_object_size(obj, 0)
56
57#define __compiletime_warning(message) __attribute__((__warning__(message)))
58#define __compiletime_error(message) __attribute__((__error__(message)))
59
60#if defined(LATENT_ENTROPY_PLUGIN) && !defined(__CHECKER__)
61#define __latent_entropy __attribute__((latent_entropy))
62#endif
63
64/*
65 * calling noreturn functions, __builtin_unreachable() and __builtin_trap()
66 * confuse the stack allocation in gcc, leading to overly large stack
67 * frames, see https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82365
68 *
69 * Adding an empty inline assembly before it works around the problem
70 */
71#define barrier_before_unreachable() asm volatile("")
72
73/*
74 * Mark a position in code as unreachable. This can be used to
75 * suppress control flow warnings after asm blocks that transfer
76 * control elsewhere.
77 */
78#define unreachable() \
79 do { \
80 annotate_unreachable(); \
81 barrier_before_unreachable(); \
82 __builtin_unreachable(); \
83 } while (0)
84
85#if defined(RANDSTRUCT_PLUGIN) && !defined(__CHECKER__)
86#define __randomize_layout __attribute__((randomize_layout))
87#define __no_randomize_layout __attribute__((no_randomize_layout))
88/* This anon struct can add padding, so only enable it under randstruct. */
89#define randomized_struct_fields_start struct {
90#define randomized_struct_fields_end } __randomize_layout;
91#endif
92
93/*
94 * GCC 'asm goto' miscompiles certain code sequences:
95 *
96 * http://gcc.gnu.org/bugzilla/show_bug.cgi?id=58670
97 *
98 * Work it around via a compiler barrier quirk suggested by Jakub Jelinek.
99 *
100 * (asm goto is automatically volatile - the naming reflects this.)
101 */
102#define asm_volatile_goto(x...) do { asm goto(x); asm (""); } while (0)
103
104/*
105 * sparse (__CHECKER__) pretends to be gcc, but can't do constant
106 * folding in __builtin_bswap*() (yet), so don't set these for it.
107 */
108#if defined(CONFIG_ARCH_USE_BUILTIN_BSWAP) && !defined(__CHECKER__)
109#define __HAVE_BUILTIN_BSWAP32__
110#define __HAVE_BUILTIN_BSWAP64__
111#define __HAVE_BUILTIN_BSWAP16__
112#endif /* CONFIG_ARCH_USE_BUILTIN_BSWAP && !__CHECKER__ */
113
114#if GCC_VERSION >= 70000
115#define KASAN_ABI_VERSION 5
116#elif GCC_VERSION >= 50000
117#define KASAN_ABI_VERSION 4
118#elif GCC_VERSION >= 40902
119#define KASAN_ABI_VERSION 3
120#endif
121
122#if __has_attribute(__no_sanitize_address__)
123#define __no_sanitize_address __attribute__((no_sanitize_address))
124#else
125#define __no_sanitize_address
126#endif
127
128#if defined(__SANITIZE_THREAD__) && __has_attribute(__no_sanitize_thread__)
129#define __no_sanitize_thread __attribute__((no_sanitize_thread))
130#else
131#define __no_sanitize_thread
132#endif
133
134#if __has_attribute(__no_sanitize_undefined__)
135#define __no_sanitize_undefined __attribute__((no_sanitize_undefined))
136#else
137#define __no_sanitize_undefined
138#endif
139
140#if GCC_VERSION >= 50100
141#define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1
142#endif
143
144/*
145 * Turn individual warnings and errors on and off locally, depending
146 * on version.
147 */
148#define __diag_GCC(version, severity, s) \
149 __diag_GCC_ ## version(__diag_GCC_ ## severity s)
150
151/* Severity used in pragma directives */
152#define __diag_GCC_ignore ignored
153#define __diag_GCC_warn warning
154#define __diag_GCC_error error
155
156#define __diag_str1(s) #s
157#define __diag_str(s) __diag_str1(s)
158#define __diag(s) _Pragma(__diag_str(GCC diagnostic s))
159
160#if GCC_VERSION >= 80000
161#define __diag_GCC_8(s) __diag(s)
162#else
163#define __diag_GCC_8(s)
164#endif