From 07a368b3f55a79d33cad113d506b279e04fd2a00 Mon Sep 17 00:00:00 2001 From: Maxim Levitsky Date: Tue, 25 Oct 2022 15:47:27 +0300 Subject: bug: introduce ASSERT_STRUCT_OFFSET ASSERT_STRUCT_OFFSET allows to assert during the build of the kernel that a field in a struct have an expected offset. KVM used to have such macro, but there is almost nothing KVM specific in it so move it to build_bug.h, so that it can be used in other places in KVM. Signed-off-by: Maxim Levitsky Message-Id: <20221025124741.228045-10-mlevitsk@redhat.com> Signed-off-by: Paolo Bonzini --- include/linux/build_bug.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'include/linux/build_bug.h') diff --git a/include/linux/build_bug.h b/include/linux/build_bug.h index e3a0be2c90ad..3aa3640f8c18 100644 --- a/include/linux/build_bug.h +++ b/include/linux/build_bug.h @@ -77,4 +77,13 @@ #define static_assert(expr, ...) __static_assert(expr, ##__VA_ARGS__, #expr) #define __static_assert(expr, msg, ...) _Static_assert(expr, msg) + +/* + * Compile time check that field has an expected offset + */ +#define ASSERT_STRUCT_OFFSET(type, field, expected_offset) \ + BUILD_BUG_ON_MSG(offsetof(type, field) != (expected_offset), \ + "Offset of " #field " in " #type " has changed.") + + #endif /* _LINUX_BUILD_BUG_H */ -- cgit