[PATCH 2/2] LoongArch: Include KBUILD_CPPFLAGS in CHECKFLAGS invocation

[WANG Xuerui]

From: WANG Xuerui <git@xxxxxxxxxx>

This is a port of commit 08f6554ff90e ("mips: Include KBUILD_CPPFLAGS
in CHECKFLAGS invocation") to arch/loongarch, for fixing
cross-compilation of Linux/LoongArch with Clang, where previously the
`--target` flag would no longer be present for the CHECKFLAGS cc
invocation leading to build failure.

Reported-by: Nathan Chancellor <nathan@xxxxxxxxxx>
Link: https://github.com/ClangBuiltLinux/linux/issues/1787#issuecomment-1608306002
Signed-off-by: WANG Xuerui <git@xxxxxxxxxx>
---
 arch/loongarch/Makefile | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/loongarch/Makefile b/arch/loongarch/Makefile
index a63683da3bcf..09ba338a64de 100644
--- a/arch/loongarch/Makefile
+++ b/arch/loongarch/Makefile
@@ -112,7 +112,7 @@ KBUILD_CFLAGS += -isystem $(shell $(CC) -print-file-name=include)
 KBUILD_LDFLAGS	+= -m $(ld-emul)
 
 ifdef CONFIG_LOONGARCH
-CHECKFLAGS += $(shell $(CC) $(KBUILD_CFLAGS) -dM -E -x c /dev/null | \
+CHECKFLAGS += $(shell $(CC) $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) -dM -E -x c /dev/null | \
 	grep -E -vw '__GNUC_(MINOR_|PATCHLEVEL_)?_' | \
 	sed -e "s/^\#define /-D'/" -e "s/ /'='/" -e "s/$$/'/" -e 's/\$$/&&/g')
 endif
-- 
2.40.0