include/linux/compiler-clang.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef __LINUX_COMPILER_TYPES_H
   3 #error "Please don't include <linux/compiler-clang.h> directly, include <linux/compiler.h> instead."
   4 #endif
   5
   6 /* Compiler specific definitions for Clang compiler */
   7
   8 /* same as gcc, this was present in clang-2.6 so we can assume it works
   9  * with any version that can compile the kernel
  10  */
  11 #define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__)
  12
  13 /* all clang versions usable with the kernel support KASAN ABI version 5 */
  14 #define KASAN_ABI_VERSION 5
  15
  16 /*
  17  * Note: Checking __has_feature(*_sanitizer) is only true if the feature is
  18  * enabled. Therefore it is not required to additionally check defined(CONFIG_*)
  19  * to avoid adding redundant attributes in other configurations.
  20  */
  21
  22 #if __has_feature(address_sanitizer) || __has_feature(hwaddress_sanitizer)
  23 /* Emulate GCC's __SANITIZE_ADDRESS__ flag */
  24 #define __SANITIZE_ADDRESS__
  25 #define __no_sanitize_address \
  26                 __attribute__((no_sanitize("address", "hwaddress")))
  27 #else
  28 #define __no_sanitize_address
  29 #endif
  30
  31 #if __has_feature(thread_sanitizer)
  32 /* emulate gcc's __SANITIZE_THREAD__ flag */
  33 #define __SANITIZE_THREAD__
  34 #define __no_sanitize_thread \
  35                 __attribute__((no_sanitize("thread")))
  36 #else
  37 #define __no_sanitize_thread
  38 #endif
  39
  40 #if defined(CONFIG_ARCH_USE_BUILTIN_BSWAP)
  41 #define __HAVE_BUILTIN_BSWAP32__
  42 #define __HAVE_BUILTIN_BSWAP64__
  43 #define __HAVE_BUILTIN_BSWAP16__
  44 #endif /* CONFIG_ARCH_USE_BUILTIN_BSWAP */
  45
  46 #if __has_feature(undefined_behavior_sanitizer)
  47 /* GCC does not have __SANITIZE_UNDEFINED__ */
  48 #define __no_sanitize_undefined \
  49                 __attribute__((no_sanitize("undefined")))
  50 #else
  51 #define __no_sanitize_undefined
  52 #endif
  53
  54 #if __has_feature(memory_sanitizer)
  55 #define __SANITIZE_MEMORY__
  56 /*
  57  * Unlike other sanitizers, KMSAN still inserts code into functions marked with
  58  * no_sanitize("kernel-memory"). Using disable_sanitizer_instrumentation
  59  * provides the behavior consistent with other __no_sanitize_ attributes,
  60  * guaranteeing that __no_sanitize_memory functions remain uninstrumented.
  61  */
  62 #define __no_sanitize_memory __disable_sanitizer_instrumentation
  63
  64 /*
  65  * The __no_kmsan_checks attribute ensures that a function does not produce
  66  * false positive reports by:
  67  *  - initializing all local variables and memory stores in this function;
  68  *  - skipping all shadow checks;
  69  *  - passing initialized arguments to this function's callees.
  70  */
  71 #define __no_kmsan_checks __attribute__((no_sanitize("kernel-memory")))
  72 #else
  73 #define __no_sanitize_memory
  74 #define __no_kmsan_checks
  75 #endif
  76
  77 /*
  78  * Support for __has_feature(coverage_sanitizer) was added in Clang 13 together
  79  * with no_sanitize("coverage"). Prior versions of Clang support coverage
  80  * instrumentation, but cannot be queried for support by the preprocessor.
  81  */
  82 #if __has_feature(coverage_sanitizer)
  83 #define __no_sanitize_coverage __attribute__((no_sanitize("coverage")))
  84 #else
  85 #define __no_sanitize_coverage
  86 #endif
  87
  88 #if __has_feature(shadow_call_stack)
  89 # define __noscs        __attribute__((__no_sanitize__("shadow-call-stack")))
  90 #endif
  91
  92 #if __has_feature(kcfi)
  93 /* Disable CFI checking inside a function. */
  94 #define __nocfi         __attribute__((__no_sanitize__("kcfi")))
  95 #endif
  96
  97 /*
  98  * Turn individual warnings and errors on and off locally, depending
  99  * on version.
 100  */
 101 #define __diag_clang(version, severity, s) \
 102         __diag_clang_ ## version(__diag_clang_ ## severity s)
 103
 104 /* Severity used in pragma directives */
 105 #define __diag_clang_ignore     ignored
 106 #define __diag_clang_warn       warning
 107 #define __diag_clang_error      error
 108
 109 #define __diag_str1(s)          #s
 110 #define __diag_str(s)           __diag_str1(s)
 111 #define __diag(s)               _Pragma(__diag_str(clang diagnostic s))
 112
 113 #if CONFIG_CLANG_VERSION >= 110000
 114 #define __diag_clang_11(s)      __diag(s)
 115 #else
 116 #define __diag_clang_11(s)
 117 #endif
 118
 119 #define __diag_ignore_all(option, comment) \
 120         __diag_clang(11, ignore, option)