Hi Masahiro, Thanks for your comments. El Fri, Apr 21, 2017 at 05:24:31PM +0900 Masahiro Yamada ha dit: > 2017-04-11 6:09 GMT+09:00 Matthias Kaehlcke <mka@xxxxxxxxxxxx>: > > > > COMPILER is previously set to "clang" if CC=clang was set from the > > make command line. So -target and -gcc-toolchain can be added to CC, > > since we already know that it is set. > > Can you reword or delete this paragraph? > I think this is confusing because COMPILER was replaced with cc-name > by commit 5631d9c4. Ok, I think not much is lost by deleting it. <snip> > > -KBUILD_CPPFLAGS := -D__KERNEL__ > > +KBUILD_CPPFLAGS := -D__KERNEL__ $(CLANG_FLAGS) > > > > KBUILD_CFLAGS := -Wall -Wundef -Wstrict-prototypes -Wno-trigraphs \ > > -fno-strict-aliasing -fno-common \ > > -Werror-implicit-function-declaration \ > > -Wno-format-security \ > > - -std=gnu89 $(call cc-option,-fno-PIE) > > - > > + -std=gnu89 $(call cc-option,-fno-PIE) \ > > + $(CLANG_FLAGS) > > > > KBUILD_AFLAGS_KERNEL := > > KBUILD_CFLAGS_KERNEL := > > -KBUILD_AFLAGS := -D__ASSEMBLY__ $(call cc-option,-fno-PIE) > > +KBUILD_AFLAGS := -D__ASSEMBLY__ $(call cc-option,-fno-PIE) $(CLANG_FLAGS) > > > This adds multiple -gcc-toolchain because both KBUILD_CPPFLAGS and KBUILD_CFLAGS > are added to c_flags. See scripts/Makefile.lib > > orig_c_flags = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) $(KBUILD_SUBDIR_CCFLAGS) \ > $(ccflags-y) $(CFLAGS_$(basetarget).o) > > > Pre-processing is related to the front-end part, > so -target and -gcc-toolchain are not necessary for KBUILD_CPPFLAGS? > > Maybe, adding it to KBUILD_CFLAGS and KBUILD_AFLAGS could be enough? Indeed it seems it is not needed in KBUILD_CPPFLAGS, at least I encountered no issues in a x86 and arm64 build. > Is it possible to move these to around line 700? > > ifeq ($(cc-name),clang) > < add here ? > > KBUILD_CPPFLAGS += $(call cc-option,-Qunused-arguments,) > KBUILD_CPPFLAGS += $(call cc-option,-Wno-unknown-warning-option,) > > I do not want to sprinkle ugly ifeq ($(cc-name,clang). I agree, better concentrate clang specific stuff when possible. I'll rework the patch and send out an update shortly. Cheers Matthias -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
