[PATCH] kbuild: Add ability to test Clang's integrated assembler

[Nathan Chancellor]

There are some people interested in experimenting with Clang's
integrated assembler. To make it easy to do so without source
modification, allow the user to specify 'AS=clang' as part of the
make command to avoid adding '-no-integrated-as' to the {A,C}FLAGS.

Link: https://github.com/ClangBuiltLinux/linux/issues/577
Suggested-by: Dmitry Golovin <dima@xxxxxxxxxx>
Signed-off-by: Nathan Chancellor <natechancellor@xxxxxxxxx>
---
 Makefile | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/Makefile b/Makefile
index 5102b2bbd224..d77481129339 100644
--- a/Makefile
+++ b/Makefile
@@ -527,7 +527,9 @@ endif
 ifneq ($(GCC_TOOLCHAIN),)
 CLANG_FLAGS	+= --gcc-toolchain=$(GCC_TOOLCHAIN)
 endif
+ifeq ($(shell $(AS) --version 2>&1 | head -n 1 | grep clang),)
 CLANG_FLAGS	+= -no-integrated-as
+endif
 CLANG_FLAGS	+= -Werror=unknown-warning-option
 KBUILD_CFLAGS	+= $(CLANG_FLAGS)
 KBUILD_AFLAGS	+= $(CLANG_FLAGS)
-- 
2.22.0