linux-stable/include/linux/compiler-clang.h
Nick Desaulniers 1f7a44f63e compiler-clang: add build check for clang 10.0.1
Patch series "set clang minimum version to 10.0.1", v3.

Adds a compile time #error to compiler-clang.h setting the effective
minimum supported version to clang 10.0.1.  A separate patch has already
been picked up into the Documentation/ tree also confirming the version.

Next are a series of reverts. One for 32b arm is a partial revert.

Then Marco suggested fixes to KASAN docs.

Finally, improve the warning for GCC too as per Kees.

This patch (of 7):

During Plumbers 2020, we voted to just support the latest release of Clang
for now.  Add a compile time check for this.

We plan to remove workarounds for older versions now, which will break in
subtle and not so subtle ways.

Suggested-by: Sedat Dilek <sedat.dilek@gmail.com>
Suggested-by: Nathan Chancellor <natechancellor@gmail.com>
Suggested-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Reviewed-by: Sedat Dilek <sedat.dilek@gmail.com>
Acked-by: Marco Elver <elver@google.com>
Acked-by: Nathan Chancellor <natechancellor@gmail.com>
Acked-by: Sedat Dilek <sedat.dilek@gmail.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Fangrui Song <maskray@google.com>
Cc: Masahiro Yamada <masahiroy@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Will Deacon <will@kernel.org>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lkml.kernel.org/r/20200902225911.209899-1-ndesaulniers@google.com
Link: https://lkml.kernel.org/r/20200902225911.209899-2-ndesaulniers@google.com
Link: https://github.com/ClangBuiltLinux/linux/issues/9
Link: https://github.com/ClangBuiltLinux/linux/issues/941
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-10-13 18:38:26 -07:00

71 lines
2.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __LINUX_COMPILER_TYPES_H
#error "Please don't include <linux/compiler-clang.h> directly, include <linux/compiler.h> instead."
#endif
#define CLANG_VERSION (__clang_major__ * 10000 \
+ __clang_minor__ * 100 \
+ __clang_patchlevel__)
#if CLANG_VERSION < 100001
# error Sorry, your version of Clang is too old - please use 10.0.1 or newer.
#endif
/* Compiler specific definitions for Clang compiler */
/* same as gcc, this was present in clang-2.6 so we can assume it works
* with any version that can compile the kernel
*/
#define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__)
/* all clang versions usable with the kernel support KASAN ABI version 5 */
#define KASAN_ABI_VERSION 5
#if __has_feature(address_sanitizer) || __has_feature(hwaddress_sanitizer)
/* Emulate GCC's __SANITIZE_ADDRESS__ flag */
#define __SANITIZE_ADDRESS__
#define __no_sanitize_address \
__attribute__((no_sanitize("address", "hwaddress")))
#else
#define __no_sanitize_address
#endif
#if __has_feature(thread_sanitizer)
/* emulate gcc's __SANITIZE_THREAD__ flag */
#define __SANITIZE_THREAD__
#define __no_sanitize_thread \
__attribute__((no_sanitize("thread")))
#else
#define __no_sanitize_thread
#endif
#if __has_feature(undefined_behavior_sanitizer)
/* GCC does not have __SANITIZE_UNDEFINED__ */
#define __no_sanitize_undefined \
__attribute__((no_sanitize("undefined")))
#else
#define __no_sanitize_undefined
#endif
/*
* Not all versions of clang implement the type-generic versions
* of the builtin overflow checkers. Fortunately, clang implements
* __has_builtin allowing us to avoid awkward version
* checks. Unfortunately, we don't know which version of gcc clang
* pretends to be, so the macro may or may not be defined.
*/
#if __has_builtin(__builtin_mul_overflow) && \
__has_builtin(__builtin_add_overflow) && \
__has_builtin(__builtin_sub_overflow)
#define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1
#endif
/* The following are for compatibility with GCC, from compiler-gcc.h,
* and may be redefined here because they should not be shared with other
* compilers, like ICC.
*/
#define barrier() __asm__ __volatile__("" : : : "memory")
#if __has_feature(shadow_call_stack)
# define __noscs __attribute__((__no_sanitize__("shadow-call-stack")))
#endif