u-boot.git/include/linux/stddef.h, branch next

Fix sparse checks processing

2023-05-15T18:08:45+00:00

A lot of errors are encountered when building with sparse checking
activated (make C=1 or make C=2).

Many of them are fixed in Linux.

Resynchronise Makefile and include/linux/build_bug.h with Linux
kernel sources by porting the following Linux commits into u-boot:
- 6c49f359ca14 ("kbuild: disable sparse warnings about unknown attributes")
- 80591e61a0f7 ("kbuild: tell sparse about the $ARCH")
- 8788994376d8 ("linux/build_bug.h: change type to int")
- 527edbc18a70 ("build_bug.h: remove most of dummy BUILD_BUG_ON stubs for Sparse")
- c60d3b79423a ("build_bug.h: remove negative-array fallback for BUILD_BUG_ON()")
- 14e83077d55f ("include: drop pointless __compiler_offsetof indirection")

Also revert commit aa9e891c63 ("include/linux/stddef.h: avoid
'warning: preprocessor token offsetof redefined'") because the
error it creates is worse than the warning it is trying to fix.

Signed-off-by: Christophe Leroy

stddef: Avoid warning with clang with offsetof()

2022-01-13T16:13:41+00:00

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

include/linux/stddef.h: avoid 'warning: preprocessor token offsetof redefined'

2012-11-04T18:00:34+00:00

hack to avoid:

/opt/gcc-4.6.3-nolibc/powerpc-linux/bin/../lib/gcc/powerpc-linux/4.6.3/include/stddef.h:413:9: warning: preprocessor token offsetof redefined
u-boot/include/linux/stddef.h:20:9: this was the original definition

tried protecting with __KERNEL__, and #including compiler.h first.

Even tried include dir reordering to no avail:

 +++ b/config.mk
 @@ -194,7 +194,11 @@ OBJCFLAGS += --gap-fill=0xff
 gccincdir := $(shell $(CC) -print-file-name=include)

 CPPFLAGS := $(DBGFLAGS) $(OPTFLAGS) $(RELFLAGS)                \
 -       -D__KERNEL__
 +       -D__KERNEL__  \
 +       -I $(gccincdir) \
 +       -nostdinc
 +
 +#      -isystem $(gccincdir) \

 # Enable garbage collection of un-used sections for SPL
 ifeq ($(CONFIG_SPL_BUILD),y)
 @@ -227,8 +231,7 @@ CPPFLAGS += -I$(OBJTREE)/include2 -I$(OBJTREE)/include
 endif

 CPPFLAGS += -I$(TOPDIR)/include
 -CPPFLAGS += -fno-builtin -ffreestanding -nostdinc      \
 -       -isystem $(gccincdir) -pipe $(PLATFORM_CPPFLAGS)
 +CPPFLAGS += -fno-builtin -ffreestanding -pipe $(PLATFORM_CPPFLAGS)

Signed-off-by: Kim Phillips

Initial revision

2002-03-31T12:34:56+00:00