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 /*
  55  * Support for __has_feature(coverage_sanitizer) was added in Clang 13 together
  56  * with no_sanitize("coverage"). Prior versions of Clang support coverage
  57  * instrumentation, but cannot be queried for support by the preprocessor.
  58  */
  59 #if __has_feature(coverage_sanitizer)
  60 #define __no_sanitize_coverage __attribute__((no_sanitize("coverage")))
  61 #else
  62 #define __no_sanitize_coverage
  63 #endif
  64
  65 /*
  66  * Not all versions of clang implement the type-generic versions
  67  * of the builtin overflow checkers. Fortunately, clang implements
  68  * __has_builtin allowing us to avoid awkward version
  69  * checks. Unfortunately, we don't know which version of gcc clang
  70  * pretends to be, so the macro may or may not be defined.
  71  */
  72 #if __has_builtin(__builtin_mul_overflow) && \
  73     __has_builtin(__builtin_add_overflow) && \
  74     __has_builtin(__builtin_sub_overflow)
  75 #define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1
  76 #endif
  77
  78 #if __has_feature(shadow_call_stack)
  79 # define __noscs        __attribute__((__no_sanitize__("shadow-call-stack")))
  80 #endif
  81
  82 #define __nocfi         __attribute__((__no_sanitize__("cfi")))
  83 #define __cficanonical  __attribute__((__cfi_canonical_jump_table__))