[PATCH 1/3] powerpc: boot: include compiler_attributes.h

From: Nick Desaulniers
Date: Sun Nov 15 2020 - 23:36:23 EST


The kernel uses `-include` to include include/linux/compiler_types.h
into all translation units (see scripts/Makefile.lib), which #includes
compiler_attributes.h.

arch/powerpc/boot/ uses different compiler flags from the rest of the
kernel. As such, it doesn't contain the definitions from these headers,
and redefines a few that it needs.

For the purpose of enabling -Wimplicit-fallthrough for ppc, include
compiler_types.h via `-include`.

Link: https://github.com/ClangBuiltLinux/linux/issues/236
Signed-off-by: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
---
We could just `#include "include/linux/compiler_types.h"` in the few .c
sources used from lib/ (there are proper header guards in
compiler_types.h).

It was also noted in 6a9dc5fd6170 that we could -D__KERNEL__ and
-include compiler_types.h like the main kernel does, though testing that
produces a whole sea of warnings to cleanup. This approach is minimally
invasive.

arch/powerpc/boot/Makefile | 1 +
arch/powerpc/boot/decompress.c | 1 -
2 files changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/boot/Makefile b/arch/powerpc/boot/Makefile
index f8ce6d2dde7b..1659963a8f1d 100644
--- a/arch/powerpc/boot/Makefile
+++ b/arch/powerpc/boot/Makefile
@@ -31,6 +31,7 @@ endif
BOOTCFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \
-fno-strict-aliasing -O2 -msoft-float -mno-altivec -mno-vsx \
-pipe -fomit-frame-pointer -fno-builtin -fPIC -nostdinc \
+ -include $(srctree)/include/linux/compiler_attributes.h \
$(LINUXINCLUDE)

ifdef CONFIG_PPC64_BOOT_WRAPPER
diff --git a/arch/powerpc/boot/decompress.c b/arch/powerpc/boot/decompress.c
index 8bf39ef7d2df..6098b879ac97 100644
--- a/arch/powerpc/boot/decompress.c
+++ b/arch/powerpc/boot/decompress.c
@@ -21,7 +21,6 @@

#define STATIC static
#define INIT
-#define __always_inline inline

/*
* The build process will copy the required zlib source files and headers
--
2.29.2.299.gdc1121823c-goog