Bob, this is ACPICA material.
Would it be possible to apply this to the upstream from the patch or do
you need a PR for this?
On 9/27/2021 2:13 PM, Arnd Bergmann wrote:
From: Arnd Bergmann <arnd@xxxxxxxx>
There are some very old macros for doing an open-coded offsetof() and
cast between pointer and integer in ACPI headers. clang-14 now complains
about these:
drivers/acpi/acpica/tbfadt.c:86:3: error: performing pointer subtraction with a null pointer has undefined behavior [-Werror,-Wnull-pointer-subtraction]
ACPI_FADT_OFFSET(pm_timer_block),
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/acpi/actbl.h:376:47: note: expanded from macro 'ACPI_FADT_OFFSET'
#define ACPI_FADT_OFFSET(f) (u16) ACPI_OFFSET (struct acpi_table_fadt, f)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/acpi/actypes.h:511:41: note: expanded from macro 'ACPI_OFFSET'
#define ACPI_OFFSET(d, f) ACPI_PTR_DIFF (&(((d *) 0)->f), (void *) 0)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/acpi/actypes.h:505:79: note: expanded from macro 'ACPI_PTR_DIFF'
#define ACPI_PTR_DIFF(a, b) ((acpi_size) (ACPI_CAST_PTR (u8, (a)) - ACPI_CAST_PTR (u8, (b))))
^ ~~~~~~~~~~~~~~~~~~~~~~~
Convert them to the modern equivalents.
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
include/acpi/actypes.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h
index 92c71dfce0d5..285bc7b73de3 100644
--- a/include/acpi/actypes.h
+++ b/include/acpi/actypes.h
@@ -507,8 +507,8 @@ typedef u64 acpi_integer;
/* Pointer/Integer type conversions */
#define ACPI_TO_POINTER(i) ACPI_CAST_PTR (void, (acpi_size) (i))
-#define ACPI_TO_INTEGER(p) ACPI_PTR_DIFF (p, (void *) 0)
-#define ACPI_OFFSET(d, f) ACPI_PTR_DIFF (&(((d *) 0)->f), (void *) 0)
+#define ACPI_TO_INTEGER(p) ((uintptr_t)(p))
+#define ACPI_OFFSET(d, f) offsetof(d, f)
#define ACPI_PHYSADDR_TO_PTR(i) ACPI_TO_POINTER(i)
#define ACPI_PTR_TO_PHYSADDR(i) ACPI_TO_INTEGER(i)
