Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
compiler_types: Identify compiler versions for __builtin_dynamic_object_size
Clarify when __builtin_dynamic_object_size() is available. All our
supported Clang versions support it. GCC 12 and later support it. Link
to documentation for both.
Acked-by: Miguel Ojeda <ojeda@kernel.org>
Link: https://lore.kernel.org/r/20250416172016.work.154-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
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+5
include/linux/compiler_types.h
+5
include/linux/compiler_types.h
···
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/*
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* When the size of an allocated object is needed, use the best available
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* mechanism to find it. (For cases where sizeof() cannot be used.)
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*
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* Optional: only supported since gcc >= 12
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*
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* gcc: https://gcc.gnu.org/onlinedocs/gcc/Object-Size-Checking.html
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* clang: https://clang.llvm.org/docs/LanguageExtensions.html#evaluating-object-size
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*/
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#if __has_builtin(__builtin_dynamic_object_size)
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#define __struct_size(p) __builtin_dynamic_object_size(p, 0)