From: Qian Cai <cai@xxxxxx>
Subject: mm: silence -Woverride-init/initializer-overrides
When compiling a kernel with W=1, there are several of those warnings due
to arm64 overriding a field on purpose. Just disable those warnings for
both GCC and Clang of this file, so it will help dig "gems" hidden in the
W=1 warnings by reducing some noises.
mm/init-mm.c:39:2: warning: initializer overrides prior initialization
of this subobject [-Winitializer-overrides]
INIT_MM_CONTEXT(init_mm)
^~~~~~~~~~~~~~~~~~~~~~~~
./arch/arm64/include/asm/mmu.h:133:9: note: expanded from macro
'INIT_MM_CONTEXT'
.pgd = init_pg_dir,
^~~~~~~~~~~
mm/init-mm.c:30:10: note: previous initialization is here
.pgd = swapper_pg_dir,
^~~~~~~~~~~~~~
Note: there is a side project trying to support explicitly allowing
specific initializer overrides in Clang, but there is no guarantee it
will happen or not.
https://github.com/ClangBuiltLinux/linux/issues/639
Link: http://lkml.kernel.org/r/1566920867-27453-1-git-send-email-cai@xxxxxx
Signed-off-by: Qian Cai <cai@xxxxxx>
Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
Cc: Mark Rutland <mark.rutland@xxxxxxx>
Cc: Arnd Bergmann <arnd@xxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
mm/Makefile | 3 +++
1 file changed, 3 insertions(+)
--- a/mm/Makefile~mm-silence-woverride-init-initializer-overrides
+++ a/mm/Makefile
@@ -21,6 +21,9 @@ KCOV_INSTRUMENT_memcontrol.o := n
KCOV_INSTRUMENT_mmzone.o := n
KCOV_INSTRUMENT_vmstat.o := n
+CFLAGS_init-mm.o += $(call cc-disable-warning, override-init)
+CFLAGS_init-mm.o += $(call cc-disable-warning, initializer-overrides)
+
mmu-y := nommu.o
mmu-$(CONFIG_MMU) := highmem.o memory.o mincore.o \
mlock.o mmap.o mmu_gather.o mprotect.o mremap.o \
_
