4.4-stable review patch. If anyone has any objections, please let me know.
------------------
From: Masahiro Yamada yamada.masahiro@socionext.com
commit cfe17c9bbe6a673fdafdab179c32b355ed447f66 upstream.
Geert reported commit ae6b289a3789 ("kbuild: Set KBUILD_CFLAGS before incl. arch Makefile") broke cross-compilation using a cross-compiler that supports less compiler options than the host compiler.
For example,
cc1: error: unrecognized command line option "-Wno-unused-but-set-variable"
This problem happens on architectures that setup CROSS_COMPILE in their arch/*/Makefile.
Move the cc-option and cc-disable-warning back to the original position, but keep the Clang target options untouched.
Fixes: ae6b289a3789 ("kbuild: Set KBUILD_CFLAGS before incl. arch Makefile") Reported-by: Geert Uytterhoeven geert@linux-m68k.org Signed-off-by: Masahiro Yamada yamada.masahiro@socionext.com Tested-by: Geert Uytterhoeven geert@linux-m68k.org [nc: Adjust context] Signed-off-by: Nathan Chancellor natechancellor@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- Makefile | 43 +++++++++++++++++++++++-------------------- 1 file changed, 23 insertions(+), 20 deletions(-)
--- a/Makefile +++ b/Makefile @@ -622,26 +622,6 @@ CLANG_GCC_TC := -gcc-toolchain $(GCC_TOO endif KBUILD_CFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) KBUILD_AFLAGS += $(CLANG_TARGET) $(CLANG_GCC_TC) -KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,) -KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable) -KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier) -KBUILD_CFLAGS += $(call cc-disable-warning, gnu) -KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member) -# Quiet clang warning: comparison of unsigned expression < 0 is always false -KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare) -# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the -# source of a reference will be _MergedGlobals and not on of the whitelisted names. -# See modpost pattern 2 -KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,) -KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior) -KBUILD_CFLAGS += $(call cc-option, -no-integrated-as) -KBUILD_AFLAGS += $(call cc-option, -no-integrated-as) -else - -# These warnings generated too much noise in a regular build. -# Use make W=1 to enable them (see scripts/Makefile.build) -KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable) -KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable) endif
# The arch Makefile can set ARCH_{CPP,A,C}FLAGS to override the default @@ -729,6 +709,29 @@ endif endif KBUILD_CFLAGS += $(stackp-flag)
+ifeq ($(cc-name),clang) +KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,) +KBUILD_CFLAGS += $(call cc-disable-warning, unused-variable) +KBUILD_CFLAGS += $(call cc-disable-warning, format-invalid-specifier) +KBUILD_CFLAGS += $(call cc-disable-warning, gnu) +KBUILD_CFLAGS += $(call cc-disable-warning, address-of-packed-member) +# Quiet clang warning: comparison of unsigned expression < 0 is always false +KBUILD_CFLAGS += $(call cc-disable-warning, tautological-compare) +# CLANG uses a _MergedGlobals as optimization, but this breaks modpost, as the +# source of a reference will be _MergedGlobals and not on of the whitelisted names. +# See modpost pattern 2 +KBUILD_CFLAGS += $(call cc-option, -mno-global-merge,) +KBUILD_CFLAGS += $(call cc-option, -fcatch-undefined-behavior) +KBUILD_CFLAGS += $(call cc-option, -no-integrated-as) +KBUILD_AFLAGS += $(call cc-option, -no-integrated-as) +else + +# These warnings generated too much noise in a regular build. +# Use make W=1 to enable them (see scripts/Makefile.extrawarn) +KBUILD_CFLAGS += $(call cc-disable-warning, unused-but-set-variable) +KBUILD_CFLAGS += $(call cc-disable-warning, unused-const-variable) +endif + ifdef CONFIG_FRAME_POINTER KBUILD_CFLAGS += -fno-omit-frame-pointer -fno-optimize-sibling-calls else