kbuild: remove AS variable

commit aa824e0c962b532d5073cbb41b2efcd6f5e72bae upstream.

As commit 5ef872636ca7 ("kbuild: get rid of misleading $(AS) from
documents") noted, we rarely use $(AS) directly in the kernel build.

Now that the only/last user of $(AS) in drivers/net/wan/Makefile was
converted to $(CC), $(AS) is no longer used in the build process.

You can still pass in AS=clang, which is just a switch to turn on
the LLVM integrated assembler.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/Makefile b/Makefile
index 1ccab8a919287ed1004446b4d0441de03e93b5e8..e5ab1905d39a7eecd3a8b691d83f0c3cdb4019fb 100644 (file)
--- a/Makefile
+++ b/Makefile
@@ -404,7 +404,6 @@ KBUILD_HOSTLDFLAGS  := $(HOST_LFS_LDFLAGS) $(HOSTLDFLAGS)
 KBUILD_HOSTLDLIBS   := $(HOST_LFS_LIBS) $(HOSTLDLIBS)
 
 # Make variables (CC, etc...)
-AS             = $(CROSS_COMPILE)as
 LD             = $(CROSS_COMPILE)ld
 CC             = $(CROSS_COMPILE)gcc
 CPP            = $(CC) -E
@@ -471,7 +470,7 @@ KBUILD_LDFLAGS :=
 GCC_PLUGINS_CFLAGS :=
 CLANG_FLAGS :=
 
-export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE AS LD CC
+export ARCH SRCARCH CONFIG_SHELL BASH HOSTCC KBUILD_HOSTCFLAGS CROSS_COMPILE LD CC
 export CPP AR NM STRIP OBJCOPY OBJDUMP OBJSIZE READELF PAHOLE LEX YACC AWK INSTALLKERNEL
 export PERL PYTHON PYTHON3 CHECK CHECKFLAGS MAKE UTS_MACHINE HOSTCXX
 export KBUILD_HOSTCXXFLAGS KBUILD_HOSTLDFLAGS KBUILD_HOSTLDLIBS LDFLAGS_MODULE
@@ -534,7 +533,7 @@ endif
 ifneq ($(GCC_TOOLCHAIN),)
 CLANG_FLAGS    += --gcc-toolchain=$(GCC_TOOLCHAIN)
 endif
-ifeq ($(shell $(AS) --version 2>&1 | head -n 1 | grep clang),)
+ifeq ($(if $(AS),$(shell $(AS) --version 2>&1 | head -n 1 | grep clang)),)
 CLANG_FLAGS    += -no-integrated-as
 endif
 CLANG_FLAGS    += -Werror=unknown-warning-option