From: Matthias Kaehlcke <m...@chromium.org>
commit 20c6c189045539d29f4854d92b7ea9c329e1edfc upstream.
The clang warning 'address-of-packed-member' is disabled for the general
kernel code, also disable it for the x86 boot code.
This suppresses a bunch of warnings like this when building with clang:
./arch/x86/include/asm/processor.h:535:30: warning: taking address of
packed member 'sp0' of class or structure 'x86_hw_tss' may result in an
unaligned pointer value [-Waddress-of-packed-member]
return this_cpu_read_stable(cpu_tss.x86_tss.sp0);
^~~~~~~~~~~~~~~~~~~
./arch/x86/include/asm/percpu.h:391:59: note: expanded from macro
'this_cpu_read_stable'
#define this_cpu_read_stable(var) percpu_stable_op("mov", var)
^~~
./arch/x86/include/asm/percpu.h:228:16: note: expanded from macro
'percpu_stable_op'
: "p" (&(var)));
^~~
Signed-off-by: Matthias Kaehlcke <m...@chromium.org>
Cc: Doug Anderson <diand...@chromium.org>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: Masahiro Yamada <yamada.masah...@socionext.com>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Thomas Gleixner <t...@linutronix.de>
Link: http://lkml.kernel.org/r/20170725215053.135586-1-...@chromium.org
Signed-off-by: Ingo Molnar <mi...@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
arch/x86/boot/compressed/Makefile | 1 +
1 file changed, 1 insertion(+)
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -30,6 +30,7 @@ KBUILD_CFLAGS += $(cflags-y)
KBUILD_CFLAGS += -mno-mmx -mno-sse
KBUILD_CFLAGS += $(call cc-option,-ffreestanding)
KBUILD_CFLAGS += $(call cc-option,-fno-stack-protector)
+KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member)
KBUILD_AFLAGS := $(KBUILD_CFLAGS) -D__ASSEMBLY__
GCOV_PROFILE := n
