On Fri, 2019-07-26 at 19:35 +0000, Moore, Robert wrote: > We've taken the change to ACPI_TO_POINTER. I am a bit confused here. I saw the commit in the acpia repo. https://github.com/acpica/acpica/commit/02bbca5070e42d298c9b824300aa0eb8a082d797 but how does that change will go into the linux kernel? Suppose Rafael will need to pick it up manually? > > > -----Original Message----- > From: Qian Cai [mailto:cai@xxxxxx] ; > Sent: Thursday, July 18, 2019 12:49 PM > To: Wysocki, Rafael J <rafael.j.wysocki@xxxxxxxxx> > Cc: Moore, Robert <robert.moore@xxxxxxxxx>; Schmauss, Erik <erik.schmauss@inte > l.com>; jkim@xxxxxxxxxxx; lenb@xxxxxxxxxx; ndesaulniers@xxxxxxxxxx; linux-acpi > @vger.kernel.org; devel@xxxxxxxxxx; clang-built-linux@xxxxxxxxxxxxxxxx; linux- > kernel@xxxxxxxxxxxxxxx; Qian Cai <cai@xxxxxx> > Subject: [PATCH v2] acpica: fix -Wnull-pointer-arithmetic warnings > > Clang generate quite a few of those warnings. > > drivers/acpi/scan.c:759:28: warning: arithmetic on a null pointer treated as a > cast from integer to pointer is a GNU extension [-Wnull-pointer-arithmetic] > status = acpi_get_handle(ACPI_ROOT_OBJECT, > obj->string.pointer, > ^~~~~~~~~~~~~~~~ > ./include/acpi/actypes.h:458:56: note: expanded from macro 'ACPI_ROOT_OBJECT' > #define ACPI_ROOT_OBJECT ((acpi_handle) ACPI_TO_POINTER > (ACPI_MAX_PTR)) > ^~~~~~~~~~~~~~~ > ./include/acpi/actypes.h:509:41: note: expanded from macro 'ACPI_TO_POINTER' > #define ACPI_TO_POINTER(i) ACPI_ADD_PTR (void, (void *) 0, > (acpi_size) (i)) > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > ./include/acpi/actypes.h:503:84: note: expanded from macro 'ACPI_ADD_PTR' > #define ACPI_ADD_PTR(t, a, b) ACPI_CAST_PTR (t, > (ACPI_CAST_PTR (u8, (a)) + (acpi_size)(b))) > ^~~~~~~~~~~~~~~~~ > ./include/acpi/actypes.h:501:66: note: expanded from macro 'ACPI_CAST_PTR' > #define ACPI_CAST_PTR(t, p) ((t *) (acpi_uintptr_t) (p)) > ^ This is > because pointer arithmetic on a pointer not pointing to an array is an > undefined behavior (C11 6.5.6, constraint 8). Fix it by just casting the > corresponding pointers using ACPI_CAST_PTR() and skip the arithmetic. Also, > fix a checkpatch warning together. > > ERROR: Macros with complex values should be enclosed in parentheses > #45: FILE: include/acpi/actypes.h:509: > +#define ACPI_TO_POINTER(i) ACPI_CAST_PTR (void, i) > > Signed-off-by: Qian Cai <cai@xxxxxx> > --- > > v2: Use ACPI_CAST_PTR() in ACPI_TO_POINTER() directly without > arithmetic. > > include/acpi/actypes.h | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/include/acpi/actypes.h b/include/acpi/actypes.h index > ad6892a24015..163181e2d884 100644 > --- a/include/acpi/actypes.h > +++ b/include/acpi/actypes.h > @@ -506,7 +506,7 @@ typedef u64 acpi_integer; > > /* Pointer/Integer type conversions */ > > -#define ACPI_TO_POINTER(i) ACPI_ADD_PTR (void, (void *) 0, > (acpi_size) (i)) > +#define ACPI_TO_POINTER(i) (ACPI_CAST_PTR (void, 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_PHYSADDR_TO_PTR(i) ACPI_TO_POINTER(i) > -- > 2.20.1 (Apple Git-117) >
