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1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef __LINUX_COMPILER_TYPES_H
3#define __LINUX_COMPILER_TYPES_H
4
5/*
6 * __has_builtin is supported on gcc >= 10, clang >= 3 and icc >= 21.
7 * In the meantime, to support gcc < 10, we implement __has_builtin
8 * by hand.
9 */
10#ifndef __has_builtin
11#define __has_builtin(x) (0)
12#endif
13
14/* Indirect macros required for expanded argument pasting, eg. __LINE__. */
15#define ___PASTE(a, b) a##b
16#define __PASTE(a, b) ___PASTE(a, b)
17
18#ifndef __ASSEMBLY__
19
20/*
21 * C23 introduces "auto" as a standard way to define type-inferred
22 * variables, but "auto" has been a (useless) keyword even since K&R C,
23 * so it has always been "namespace reserved."
24 *
25 * Until at some future time we require C23 support, we need the gcc
26 * extension __auto_type, but there is no reason to put that elsewhere
27 * in the source code.
28 */
29#if __STDC_VERSION__ < 202311L
30# define auto __auto_type
31#endif
32
33/*
34 * Skipped when running bindgen due to a libclang issue;
35 * see https://github.com/rust-lang/rust-bindgen/issues/2244.
36 */
37#if defined(CONFIG_DEBUG_INFO_BTF) && defined(CONFIG_PAHOLE_HAS_BTF_TAG) && \
38 __has_attribute(btf_type_tag) && !defined(__BINDGEN__)
39# define BTF_TYPE_TAG(value) __attribute__((btf_type_tag(#value)))
40#else
41# define BTF_TYPE_TAG(value) /* nothing */
42#endif
43
44/* sparse defines __CHECKER__; see Documentation/dev-tools/sparse.rst */
45#ifdef __CHECKER__
46/* address spaces */
47# define __kernel __attribute__((address_space(0)))
48# define __user __attribute__((noderef, address_space(__user)))
49# define __iomem __attribute__((noderef, address_space(__iomem)))
50# define __percpu __attribute__((noderef, address_space(__percpu)))
51# define __rcu __attribute__((noderef, address_space(__rcu)))
52static inline void __chk_user_ptr(const volatile void __user *ptr) { }
53static inline void __chk_io_ptr(const volatile void __iomem *ptr) { }
54/* context/locking */
55# define __must_hold(x) __attribute__((context(x,1,1)))
56# define __acquires(x) __attribute__((context(x,0,1)))
57# define __cond_acquires(x) __attribute__((context(x,0,-1)))
58# define __releases(x) __attribute__((context(x,1,0)))
59# define __acquire(x) __context__(x,1)
60# define __release(x) __context__(x,-1)
61# define __cond_lock(x,c) ((c) ? ({ __acquire(x); 1; }) : 0)
62/* other */
63# define __force __attribute__((force))
64# define __nocast __attribute__((nocast))
65# define __safe __attribute__((safe))
66# define __private __attribute__((noderef))
67# define ACCESS_PRIVATE(p, member) (*((typeof((p)->member) __force *) &(p)->member))
68#else /* __CHECKER__ */
69/* address spaces */
70# define __kernel
71# ifdef STRUCTLEAK_PLUGIN
72# define __user __attribute__((user))
73# else
74# define __user BTF_TYPE_TAG(user)
75# endif
76# define __iomem
77# define __percpu __percpu_qual BTF_TYPE_TAG(percpu)
78# define __rcu BTF_TYPE_TAG(rcu)
79
80# define __chk_user_ptr(x) (void)0
81# define __chk_io_ptr(x) (void)0
82/* context/locking */
83# define __must_hold(x)
84# define __acquires(x)
85# define __cond_acquires(x)
86# define __releases(x)
87# define __acquire(x) (void)0
88# define __release(x) (void)0
89# define __cond_lock(x,c) (c)
90/* other */
91# define __force
92# define __nocast
93# define __safe
94# define __private
95# define ACCESS_PRIVATE(p, member) ((p)->member)
96# define __builtin_warning(x, y...) (1)
97#endif /* __CHECKER__ */
98
99#ifdef __KERNEL__
100
101/* Attributes */
102#include <linux/compiler_attributes.h>
103
104#if CONFIG_FUNCTION_ALIGNMENT > 0
105#define __function_aligned __aligned(CONFIG_FUNCTION_ALIGNMENT)
106#else
107#define __function_aligned
108#endif
109
110/*
111 * gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-cold-function-attribute
112 * gcc: https://gcc.gnu.org/onlinedocs/gcc/Label-Attributes.html#index-cold-label-attribute
113 *
114 * When -falign-functions=N is in use, we must avoid the cold attribute as
115 * GCC drops the alignment for cold functions. Worse, GCC can implicitly mark
116 * callees of cold functions as cold themselves, so it's not sufficient to add
117 * __function_aligned here as that will not ensure that callees are correctly
118 * aligned.
119 *
120 * See:
121 *
122 * https://lore.kernel.org/lkml/Y77%2FqVgvaJidFpYt@FVFF77S0Q05N
123 * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88345#c9
124 */
125#if defined(CONFIG_CC_HAS_SANE_FUNCTION_ALIGNMENT) || (CONFIG_FUNCTION_ALIGNMENT == 0)
126#define __cold __attribute__((__cold__))
127#else
128#define __cold
129#endif
130
131/*
132 * On x86-64 and arm64 targets, __preserve_most changes the calling convention
133 * of a function to make the code in the caller as unintrusive as possible. This
134 * convention behaves identically to the C calling convention on how arguments
135 * and return values are passed, but uses a different set of caller- and callee-
136 * saved registers.
137 *
138 * The purpose is to alleviates the burden of saving and recovering a large
139 * register set before and after the call in the caller. This is beneficial for
140 * rarely taken slow paths, such as error-reporting functions that may be called
141 * from hot paths.
142 *
143 * Note: This may conflict with instrumentation inserted on function entry which
144 * does not use __preserve_most or equivalent convention (if in assembly). Since
145 * function tracing assumes the normal C calling convention, where the attribute
146 * is supported, __preserve_most implies notrace. It is recommended to restrict
147 * use of the attribute to functions that should or already disable tracing.
148 *
149 * Optional: not supported by gcc.
150 *
151 * clang: https://clang.llvm.org/docs/AttributeReference.html#preserve-most
152 */
153#if __has_attribute(__preserve_most__) && (defined(CONFIG_X86_64) || defined(CONFIG_ARM64))
154# define __preserve_most notrace __attribute__((__preserve_most__))
155#else
156# define __preserve_most
157#endif
158
159/*
160 * Annotating a function/variable with __retain tells the compiler to place
161 * the object in its own section and set the flag SHF_GNU_RETAIN. This flag
162 * instructs the linker to retain the object during garbage-cleanup or LTO
163 * phases.
164 *
165 * Note that the __used macro is also used to prevent functions or data
166 * being optimized out, but operates at the compiler/IR-level and may still
167 * allow unintended removal of objects during linking.
168 *
169 * Optional: only supported since gcc >= 11, clang >= 13
170 *
171 * gcc: https://gcc.gnu.org/onlinedocs/gcc/Common-Function-Attributes.html#index-retain-function-attribute
172 * clang: https://clang.llvm.org/docs/AttributeReference.html#retain
173 */
174#if __has_attribute(__retain__) && \
175 (defined(CONFIG_LD_DEAD_CODE_DATA_ELIMINATION) || \
176 defined(CONFIG_LTO_CLANG))
177# define __retain __attribute__((__retain__))
178#else
179# define __retain
180#endif
181
182/* Compiler specific macros. */
183#ifdef __clang__
184#include <linux/compiler-clang.h>
185#elif defined(__GNUC__)
186/* The above compilers also define __GNUC__, so order is important here. */
187#include <linux/compiler-gcc.h>
188#else
189#error "Unknown compiler"
190#endif
191
192/*
193 * Some architectures need to provide custom definitions of macros provided
194 * by linux/compiler-*.h, and can do so using asm/compiler.h. We include that
195 * conditionally rather than using an asm-generic wrapper in order to avoid
196 * build failures if any C compilation, which will include this file via an
197 * -include argument in c_flags, occurs prior to the asm-generic wrappers being
198 * generated.
199 */
200#ifdef CONFIG_HAVE_ARCH_COMPILER_H
201#include <asm/compiler.h>
202#endif
203
204struct ftrace_branch_data {
205 const char *func;
206 const char *file;
207 unsigned line;
208 union {
209 struct {
210 unsigned long correct;
211 unsigned long incorrect;
212 };
213 struct {
214 unsigned long miss;
215 unsigned long hit;
216 };
217 unsigned long miss_hit[2];
218 };
219};
220
221struct ftrace_likely_data {
222 struct ftrace_branch_data data;
223 unsigned long constant;
224};
225
226#if defined(CC_USING_HOTPATCH)
227#define notrace __attribute__((hotpatch(0, 0)))
228#elif defined(CC_USING_PATCHABLE_FUNCTION_ENTRY)
229#define notrace __attribute__((patchable_function_entry(0, 0)))
230#else
231#define notrace __attribute__((__no_instrument_function__))
232#endif
233
234/*
235 * it doesn't make sense on ARM (currently the only user of __naked)
236 * to trace naked functions because then mcount is called without
237 * stack and frame pointer being set up and there is no chance to
238 * restore the lr register to the value before mcount was called.
239 */
240#define __naked __attribute__((__naked__)) notrace
241
242/*
243 * Prefer gnu_inline, so that extern inline functions do not emit an
244 * externally visible function. This makes extern inline behave as per gnu89
245 * semantics rather than c99. This prevents multiple symbol definition errors
246 * of extern inline functions at link time.
247 * A lot of inline functions can cause havoc with function tracing.
248 */
249#define inline inline __gnu_inline __inline_maybe_unused notrace
250
251/*
252 * gcc provides both __inline__ and __inline as alternate spellings of
253 * the inline keyword, though the latter is undocumented. New kernel
254 * code should only use the inline spelling, but some existing code
255 * uses __inline__. Since we #define inline above, to ensure
256 * __inline__ has the same semantics, we need this #define.
257 *
258 * However, the spelling __inline is strictly reserved for referring
259 * to the bare keyword.
260 */
261#define __inline__ inline
262
263/*
264 * GCC does not warn about unused static inline functions for -Wunused-function.
265 * Suppress the warning in clang as well by using __maybe_unused, but enable it
266 * for W=2 build. This will allow clang to find unused functions.
267 */
268#ifdef KBUILD_EXTRA_WARN2
269#define __inline_maybe_unused
270#else
271#define __inline_maybe_unused __maybe_unused
272#endif
273
274/*
275 * Rather then using noinline to prevent stack consumption, use
276 * noinline_for_stack instead. For documentation reasons.
277 */
278#define noinline_for_stack noinline
279
280/*
281 * Use noinline_for_tracing for functions that should not be inlined.
282 * For tracing reasons.
283 */
284#define noinline_for_tracing noinline
285
286/*
287 * Sanitizer helper attributes: Because using __always_inline and
288 * __no_sanitize_* conflict, provide helper attributes that will either expand
289 * to __no_sanitize_* in compilation units where instrumentation is enabled
290 * (__SANITIZE_*__), or __always_inline in compilation units without
291 * instrumentation (__SANITIZE_*__ undefined).
292 */
293#ifdef __SANITIZE_ADDRESS__
294/*
295 * We can't declare function 'inline' because __no_sanitize_address conflicts
296 * with inlining. Attempt to inline it may cause a build failure.
297 * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67368
298 * '__maybe_unused' allows us to avoid defined-but-not-used warnings.
299 */
300# define __no_kasan_or_inline __no_sanitize_address notrace __maybe_unused
301# define __no_sanitize_or_inline __no_kasan_or_inline
302#else
303# define __no_kasan_or_inline __always_inline
304#endif
305
306#ifdef __SANITIZE_THREAD__
307/*
308 * Clang still emits instrumentation for __tsan_func_{entry,exit}() and builtin
309 * atomics even with __no_sanitize_thread (to avoid false positives in userspace
310 * ThreadSanitizer). The kernel's requirements are stricter and we really do not
311 * want any instrumentation with __no_kcsan.
312 *
313 * Therefore we add __disable_sanitizer_instrumentation where available to
314 * disable all instrumentation. See Kconfig.kcsan where this is mandatory.
315 */
316# define __no_kcsan __no_sanitize_thread __disable_sanitizer_instrumentation
317/*
318 * Type qualifier to mark variables where all data-racy accesses should be
319 * ignored by KCSAN. Note, the implementation simply marks these variables as
320 * volatile, since KCSAN will treat such accesses as "marked".
321 */
322# define __data_racy volatile
323# define __no_sanitize_or_inline __no_kcsan notrace __maybe_unused
324#else
325# define __no_kcsan
326# define __data_racy
327#endif
328
329#ifdef __SANITIZE_MEMORY__
330/*
331 * Similarly to KASAN and KCSAN, KMSAN loses function attributes of inlined
332 * functions, therefore disabling KMSAN checks also requires disabling inlining.
333 *
334 * __no_sanitize_or_inline effectively prevents KMSAN from reporting errors
335 * within the function and marks all its outputs as initialized.
336 */
337# define __no_sanitize_or_inline __no_kmsan_checks notrace __maybe_unused
338#endif
339
340#ifndef __no_sanitize_or_inline
341#define __no_sanitize_or_inline __always_inline
342#endif
343
344/*
345 * The assume attribute is used to indicate that a certain condition is
346 * assumed to be true. If this condition is violated at runtime, the behavior
347 * is undefined. Compilers may or may not use this indication to generate
348 * optimized code.
349 *
350 * Note that the clang documentation states that optimizers may react
351 * differently to this attribute, and this may even have a negative
352 * performance impact. Therefore this attribute should be used with care.
353 *
354 * Optional: only supported since gcc >= 13
355 * Optional: only supported since clang >= 19
356 *
357 * gcc: https://gcc.gnu.org/onlinedocs/gcc/Statement-Attributes.html#index-assume-statement-attribute
358 * clang: https://clang.llvm.org/docs/AttributeReference.html#id13
359 *
360 */
361#ifdef CONFIG_CC_HAS_ASSUME
362# define __assume(expr) __attribute__((__assume__(expr)))
363#else
364# define __assume(expr)
365#endif
366
367/*
368 * Optional: only supported since gcc >= 15
369 * Optional: only supported since clang >= 18
370 *
371 * gcc: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=108896
372 * clang: https://github.com/llvm/llvm-project/pull/76348
373 *
374 * __bdos on clang < 19.1.2 can erroneously return 0:
375 * https://github.com/llvm/llvm-project/pull/110497
376 *
377 * __bdos on clang < 19.1.3 can be off by 4:
378 * https://github.com/llvm/llvm-project/pull/112636
379 */
380#ifdef CONFIG_CC_HAS_COUNTED_BY
381# define __counted_by(member) __attribute__((__counted_by__(member)))
382#else
383# define __counted_by(member)
384#endif
385
386/*
387 * Optional: only supported since gcc >= 15
388 * Optional: not supported by Clang
389 *
390 * gcc: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=117178
391 */
392#ifdef CONFIG_CC_HAS_MULTIDIMENSIONAL_NONSTRING
393# define __nonstring_array __attribute__((__nonstring__))
394#else
395# define __nonstring_array
396#endif
397
398/*
399 * Apply __counted_by() when the Endianness matches to increase test coverage.
400 */
401#ifdef __LITTLE_ENDIAN
402#define __counted_by_le(member) __counted_by(member)
403#define __counted_by_be(member)
404#else
405#define __counted_by_le(member)
406#define __counted_by_be(member) __counted_by(member)
407#endif
408
409/*
410 * This designates the minimum number of elements a passed array parameter must
411 * have. For example:
412 *
413 * void some_function(u8 param[at_least 7]);
414 *
415 * If a caller passes an array with fewer than 7 elements, the compiler will
416 * emit a warning.
417 */
418#ifndef __CHECKER__
419#define at_least static
420#else
421#define at_least
422#endif
423
424/* Do not trap wrapping arithmetic within an annotated function. */
425#ifdef CONFIG_UBSAN_INTEGER_WRAP
426# define __signed_wrap __attribute__((no_sanitize("signed-integer-overflow")))
427#else
428# define __signed_wrap
429#endif
430
431/* Section for code which can't be instrumented at all */
432#define __noinstr_section(section) \
433 noinline notrace __attribute((__section__(section))) \
434 __no_kcsan __no_sanitize_address __no_profile __no_sanitize_coverage \
435 __no_sanitize_memory __signed_wrap
436
437#define noinstr __noinstr_section(".noinstr.text")
438
439/*
440 * The __cpuidle section is used twofold:
441 *
442 * 1) the original use -- identifying if a CPU is 'stuck' in idle state based
443 * on it's instruction pointer. See cpu_in_idle().
444 *
445 * 2) supressing instrumentation around where cpuidle disables RCU; where the
446 * function isn't strictly required for #1, this is interchangeable with
447 * noinstr.
448 */
449#define __cpuidle __noinstr_section(".cpuidle.text")
450
451#endif /* __KERNEL__ */
452
453#endif /* __ASSEMBLY__ */
454
455/*
456 * The below symbols may be defined for one or more, but not ALL, of the above
457 * compilers. We don't consider that to be an error, so set them to nothing.
458 * For example, some of them are for compiler specific plugins.
459 */
460#ifndef __latent_entropy
461# define __latent_entropy
462#endif
463
464#if defined(RANDSTRUCT) && !defined(__CHECKER__)
465# define __randomize_layout __designated_init __attribute__((randomize_layout))
466# define __no_randomize_layout __attribute__((no_randomize_layout))
467/* This anon struct can add padding, so only enable it under randstruct. */
468# define randomized_struct_fields_start struct {
469# define randomized_struct_fields_end } __randomize_layout;
470#else
471# define __randomize_layout __designated_init
472# define __no_randomize_layout
473# define randomized_struct_fields_start
474# define randomized_struct_fields_end
475#endif
476
477#ifndef __no_kstack_erase
478# define __no_kstack_erase
479#endif
480
481#ifndef __noscs
482# define __noscs
483#endif
484
485#if defined(CONFIG_CFI)
486# define __nocfi __attribute__((__no_sanitize__("kcfi")))
487#else
488# define __nocfi
489#endif
490
491#if defined(CONFIG_ARCH_USES_CFI_GENERIC_LLVM_PASS)
492# define __nocfi_generic __nocfi
493#else
494# define __nocfi_generic
495#endif
496
497/*
498 * Any place that could be marked with the "alloc_size" attribute is also
499 * a place to be marked with the "malloc" attribute, except those that may
500 * be performing a _reallocation_, as that may alias the existing pointer.
501 * For these, use __realloc_size().
502 */
503#ifdef __alloc_size__
504# define __alloc_size(x, ...) __alloc_size__(x, ## __VA_ARGS__) __malloc
505# define __realloc_size(x, ...) __alloc_size__(x, ## __VA_ARGS__)
506#else
507# define __alloc_size(x, ...) __malloc
508# define __realloc_size(x, ...)
509#endif
510
511/*
512 * When the size of an allocated object is needed, use the best available
513 * mechanism to find it. (For cases where sizeof() cannot be used.)
514 *
515 * Optional: only supported since gcc >= 12
516 *
517 * gcc: https://gcc.gnu.org/onlinedocs/gcc/Object-Size-Checking.html
518 * clang: https://clang.llvm.org/docs/LanguageExtensions.html#evaluating-object-size
519 */
520#if __has_builtin(__builtin_dynamic_object_size)
521#define __struct_size(p) __builtin_dynamic_object_size(p, 0)
522#define __member_size(p) __builtin_dynamic_object_size(p, 1)
523#else
524#define __struct_size(p) __builtin_object_size(p, 0)
525#define __member_size(p) __builtin_object_size(p, 1)
526#endif
527
528/*
529 * Determine if an attribute has been applied to a variable.
530 * Using __annotated needs to check for __annotated being available,
531 * or negative tests may fail when annotation cannot be checked. For
532 * example, see the definition of __is_cstr().
533 */
534#if __has_builtin(__builtin_has_attribute)
535#define __annotated(var, attr) __builtin_has_attribute(var, attr)
536#endif
537
538/*
539 * Some versions of gcc do not mark 'asm goto' volatile:
540 *
541 * https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103979
542 *
543 * We do it here by hand, because it doesn't hurt.
544 */
545#ifndef asm_goto_output
546#define asm_goto_output(x...) asm volatile goto(x)
547#endif
548
549/*
550 * Clang has trouble with constraints with multiple
551 * alternative behaviors ("g" , "rm" and "=rm").
552 */
553#ifndef ASM_INPUT_G
554 #define ASM_INPUT_G "g"
555 #define ASM_INPUT_RM "rm"
556 #define ASM_OUTPUT_RM "=rm"
557#endif
558
559#ifdef CONFIG_CC_HAS_ASM_INLINE
560#define asm_inline asm __inline
561#else
562#define asm_inline asm
563#endif
564
565/* Are two types/vars the same type (ignoring qualifiers)? */
566#define __same_type(a, b) __builtin_types_compatible_p(typeof(a), typeof(b))
567
568/*
569 * __unqual_scalar_typeof(x) - Declare an unqualified scalar type, leaving
570 * non-scalar types unchanged.
571 */
572/*
573 * Prefer C11 _Generic for better compile-times and simpler code. Note: 'char'
574 * is not type-compatible with 'signed char', and we define a separate case.
575 */
576#define __scalar_type_to_expr_cases(type) \
577 unsigned type: (unsigned type)0, \
578 signed type: (signed type)0
579
580#define __unqual_scalar_typeof(x) typeof( \
581 _Generic((x), \
582 char: (char)0, \
583 __scalar_type_to_expr_cases(char), \
584 __scalar_type_to_expr_cases(short), \
585 __scalar_type_to_expr_cases(int), \
586 __scalar_type_to_expr_cases(long), \
587 __scalar_type_to_expr_cases(long long), \
588 default: (x)))
589
590/* Is this type a native word size -- useful for atomic operations */
591#define __native_word(t) \
592 (sizeof(t) == sizeof(char) || sizeof(t) == sizeof(short) || \
593 sizeof(t) == sizeof(int) || sizeof(t) == sizeof(long))
594
595#ifdef __OPTIMIZE__
596/*
597 * #ifdef __OPTIMIZE__ is only a good approximation; for instance "make
598 * CFLAGS_foo.o=-Og" defines __OPTIMIZE__, does not elide the conditional code
599 * and can break compilation with wrong error message(s). Combine with
600 * -U__OPTIMIZE__ when needed.
601 */
602# define __compiletime_assert(condition, msg, prefix, suffix) \
603 do { \
604 /* \
605 * __noreturn is needed to give the compiler enough \
606 * information to avoid certain possibly-uninitialized \
607 * warnings (regardless of the build failing). \
608 */ \
609 __noreturn extern void prefix ## suffix(void) \
610 __compiletime_error(msg); \
611 if (!(condition)) \
612 prefix ## suffix(); \
613 } while (0)
614#else
615# define __compiletime_assert(condition, msg, prefix, suffix) ((void)(condition))
616#endif
617
618#define _compiletime_assert(condition, msg, prefix, suffix) \
619 __compiletime_assert(condition, msg, prefix, suffix)
620
621/**
622 * compiletime_assert - break build and emit msg if condition is false
623 * @condition: a compile-time constant condition to check
624 * @msg: a message to emit if condition is false
625 *
626 * In tradition of POSIX assert, this macro will break the build if the
627 * supplied condition is *false*, emitting the supplied error message if the
628 * compiler has support to do so.
629 */
630#define compiletime_assert(condition, msg) \
631 _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__)
632
633#define compiletime_assert_atomic_type(t) \
634 compiletime_assert(__native_word(t), \
635 "Need native word sized stores/loads for atomicity.")
636
637/* Helpers for emitting diagnostics in pragmas. */
638#ifndef __diag
639#define __diag(string)
640#endif
641
642#ifndef __diag_GCC
643#define __diag_GCC(version, severity, string)
644#endif
645
646#define __diag_push() __diag(push)
647#define __diag_pop() __diag(pop)
648
649#define __diag_ignore(compiler, version, option, comment) \
650 __diag_ ## compiler(version, ignore, option)
651#define __diag_warn(compiler, version, option, comment) \
652 __diag_ ## compiler(version, warn, option)
653#define __diag_error(compiler, version, option, comment) \
654 __diag_ ## compiler(version, error, option)
655
656#ifndef __diag_ignore_all
657#define __diag_ignore_all(option, comment)
658#endif
659
660#endif /* __LINUX_COMPILER_TYPES_H */
661

source code of linux/include/linux/compiler_types.h