a3f8a30f3f
Instead of using version checks per-compiler to define (or not)
each attribute, use __has_attribute to test for them, following
the cleanup started with commit 815f0ddb34
("include/linux/compiler*.h: make compiler-*.h mutually exclusive"),
which is supported on gcc >= 5, clang >= 2.9 and icc >= 17.
In the meantime, to support 4.6 <= gcc < 5, we implement
__has_attribute by hand.
All the attributes that can be unconditionally defined and directly
map to compiler attribute(s) (even if optional) have been moved
to a new file include/linux/compiler_attributes.h
In an effort to make the file as regular as possible, comments
stating the purpose of attributes have been removed. Instead,
links to the compiler docs have been added (i.e. to gcc and,
if available, to clang as well). In addition, they have been sorted.
Finally, if an attribute is optional (i.e. if it is guarded
by __has_attribute), the reason has been stated for future reference.
Tested-by: Sedat Dilek <sedat.dilek@gmail.com> # on top of v4.19-rc5, clang 7
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
42 lines
1.4 KiB
C
42 lines
1.4 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
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#ifndef __LINUX_COMPILER_TYPES_H
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#error "Please don't include <linux/compiler-clang.h> directly, include <linux/compiler.h> instead."
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#endif
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/* Some compiler specific definitions are overwritten here
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* for Clang compiler
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*/
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#define uninitialized_var(x) x = *(&(x))
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/* same as gcc, this was present in clang-2.6 so we can assume it works
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* with any version that can compile the kernel
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*/
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#define __UNIQUE_ID(prefix) __PASTE(__PASTE(__UNIQUE_ID_, prefix), __COUNTER__)
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/* all clang versions usable with the kernel support KASAN ABI version 5 */
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#define KASAN_ABI_VERSION 5
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/* emulate gcc's __SANITIZE_ADDRESS__ flag */
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#if __has_feature(address_sanitizer)
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#define __SANITIZE_ADDRESS__
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#endif
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/*
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* Not all versions of clang implement the the type-generic versions
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* of the builtin overflow checkers. Fortunately, clang implements
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* __has_builtin allowing us to avoid awkward version
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* checks. Unfortunately, we don't know which version of gcc clang
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* pretends to be, so the macro may or may not be defined.
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*/
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#if __has_builtin(__builtin_mul_overflow) && \
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__has_builtin(__builtin_add_overflow) && \
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__has_builtin(__builtin_sub_overflow)
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#define COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW 1
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#endif
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/* The following are for compatibility with GCC, from compiler-gcc.h,
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* and may be redefined here because they should not be shared with other
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* compilers, like ICC.
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*/
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#define barrier() __asm__ __volatile__("" : : : "memory")
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