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 #if __has_feature(address_sanitizer) || __has_feature(hwaddress_sanitizer)
  17 /* Emulate GCC's __SANITIZE_ADDRESS__ flag */
  18 #define __SANITIZE_ADDRESS__
  19 #define __no_sanitize_address \
  20                 __attribute__((no_sanitize("address", "hwaddress")))
  21 #else
  22 #define __no_sanitize_address
  23 #endif
  24
  25 #if __has_feature(thread_sanitizer)
  26 /* emulate gcc's __SANITIZE_THREAD__ flag */
  27 #define __SANITIZE_THREAD__
  28 #define __no_sanitize_thread \
  29                 __attribute__((no_sanitize("thread")))
  30 #else
  31 #define __no_sanitize_thread
  32 #endif
  33
  34 #if __has_feature(undefined_behavior_sanitizer)
  35 /* GCC does not have __SANITIZE_UNDEFINED__ */
  36 #define __no_sanitize_undefined \
  37                 __attribute__((no_sanitize("undefined")))
  38 #else
  39 #define __no_sanitize_undefined
  40 #endif
  41
  42 /*
  43  * Not all versions of clang implement the the type-generic versions
  44  * of the builtin overflow checkers. Fortunately, clang implements
  45  * __has_builtin allowing us to avoid awkward version
  46  * checks. Unfortunately, we don't know which version of gcc clang
  47  * pretends to be, so the macro may or may not be defined.
  48  */
  49 #if __has_builtin(__builtin_mul_overflow) && \
  50     __has_builtin(__builtin_add_overflow) && \
  51     __has_builtin(__builtin_sub_overflow)
  52 #define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1
  53 #endif
  54
  55 /* The following are for compatibility with GCC, from compiler-gcc.h,
  56  * and may be redefined here because they should not be shared with other
  57  * compilers, like ICC.
  58  */
  59 #define barrier() __asm__ __volatile__("" : : : "memory")
  60
  61 #if __has_feature(shadow_call_stack)
  62 # define __noscs        __attribute__((__no_sanitize__("shadow-call-stack")))
  63 #endif