| Message ID | 20220113134807.544872-2-sjg@chromium.org |
|---|---|
| State | Accepted |
| Commit | 78aac05eb1de0f70f7643a575ff543211d2cc6f4 |
| Delegated to: | Simon Glass |
| Headers | show |
| Series | [v3,01/12] stddef: Avoid warning with clang with offsetof() | expand |
Some bright sparks have decided that a cast on a constant cannot be a
constant, so offsetof() produces this warning on clang-10:
include/intel_gnvs.h:113:1: error: static_assert expression is not an
integral constant expression
check_member(acpi_global_nvs, unused2, GNVS_CHROMEOS_ACPI_OFFSET);
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/kernel.h:284:2: note: expanded from macro 'check_member'
offsetof(struct structure, member) == (offset), \
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/stddef.h:20:32: note: expanded from macro 'offsetof'
^
include/intel_gnvs.h:113:1: note: cast that performs the conversions of
a reinterpret_cast is ot allowed in a constant expression
include/linux/stddef.h:20:33: note: expanded from macro 'offsetof'
Fix it by using the compiler built-in version, if available. This syncs
the function to the same implementation as Linux v5.16 in this header
file.
Signed-off-by: Simon Glass <sjg@chromium.org>
---
Changes in v3:
- Update commit message to mention this syncs with Linux
include/linux/stddef.h | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
Applied to u-boot-dm, thanks!
diff --git a/include/linux/stddef.h b/include/linux/stddef.h index c540f6100d4..a7f546fdfe5 100644 --- a/include/linux/stddef.h +++ b/include/linux/stddef.h @@ -1,6 +1,8 @@ #ifndef _LINUX_STDDEF_H #define _LINUX_STDDEF_H +#include <linux/compiler_types.h> + #undef NULL #if defined(__cplusplus) #define NULL 0 @@ -14,7 +16,11 @@ #ifndef __CHECKER__ #undef offsetof -#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER) +#ifdef __compiler_offsetof +#define offsetof(TYPE, MEMBER) __compiler_offsetof(TYPE, MEMBER) +#else +#define offsetof(TYPE, MEMBER) ((size_t)&((TYPE *)0)->MEMBER) +#endif #endif #endif
Some bright sparks have decided that a cast on a constant cannot be a constant, so offsetof() produces this warning on clang-10: include/intel_gnvs.h:113:1: error: static_assert expression is not an integral constant expression check_member(acpi_global_nvs, unused2, GNVS_CHROMEOS_ACPI_OFFSET); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/kernel.h:284:2: note: expanded from macro 'check_member' offsetof(struct structure, member) == (offset), \ ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/stddef.h:20:32: note: expanded from macro 'offsetof' ^ include/intel_gnvs.h:113:1: note: cast that performs the conversions of a reinterpret_cast is ot allowed in a constant expression include/linux/stddef.h:20:33: note: expanded from macro 'offsetof' Fix it by using the compiler built-in version, if available. This syncs the function to the same implementation as Linux v5.16 in this header file. Signed-off-by: Simon Glass <sjg@chromium.org> --- Changes in v3: - Update commit message to mention this syncs with Linux include/linux/stddef.h | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-)