The 'addtree' and 'flags' in scripts/Kbuild.include are so compilecated and ugly. As I mentioned in [1], Kbuild should stop automatic prefixing of header search path options. Instead, in-kernel Makefiles should explicitly add $(srctree)/ to the search paths in the srctree. Kbuild still caters to add $(srctree)/$(src) and $(objtree)/$(obj) to the header search path for O= building, but never touches extra compiler options from ccflags-y etc. Going forward, in-kernel Makefiles should explicitly specify $(srctree)/ if extra search paths are needed. Example) ccflags-y += -I $(srctree)/foo/bar You do not have to change external module Makefiles because $(src) is already an absolute path for external modules. Example) ccflags-y += -I $(src)/foo/bar [1]: https://patchwork.kernel.org/patch/9632347/ Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> --- scripts/Kbuild.include | 8 -------- scripts/Makefile.host | 12 +++++------- scripts/Makefile.lib | 26 ++++++++------------------ 3 files changed, 13 insertions(+), 33 deletions(-) diff --git a/scripts/Kbuild.include b/scripts/Kbuild.include index 7484b9d8272f..a675ce11a573 100644 --- a/scripts/Kbuild.include +++ b/scripts/Kbuild.include @@ -192,14 +192,6 @@ clean := -f $(srctree)/scripts/Makefile.clean obj # $(Q)$(MAKE) $(hdr-inst)=dir hdr-inst := -f $(srctree)/scripts/Makefile.headersinst obj -# Prefix -I with $(srctree) if it is not an absolute path. -# skip if -I has no parameter -addtree = $(if $(patsubst -I%,%,$(1)), \ -$(if $(filter-out -I/% -I./% -I../%,$(1)),$(patsubst -I%,-I$(srctree)/%,$(1)),$(1)),$(1)) - -# Find all -I options and call addtree -flags = $(foreach o,$($(1)),$(if $(filter -I%,$(o)),$(call addtree,$(o)),$(o))) - # echo command. # Short version is used, if $(quiet) equals `quiet_', otherwise full one. echo-cmd = $(if $($(quiet)cmd_$(1)),\ diff --git a/scripts/Makefile.host b/scripts/Makefile.host index 73b804197fca..b6a54bdf0965 100644 --- a/scripts/Makefile.host +++ b/scripts/Makefile.host @@ -67,18 +67,16 @@ _hostc_flags = $(KBUILD_HOSTCFLAGS) $(HOST_EXTRACFLAGS) \ _hostcxx_flags = $(KBUILD_HOSTCXXFLAGS) $(HOST_EXTRACXXFLAGS) \ $(HOSTCXXFLAGS_$(basetarget).o) -__hostc_flags = $(_hostc_flags) -__hostcxx_flags = $(_hostcxx_flags) - +# $(objtree)/$(obj) for including generated headers from checkin source files ifeq ($(KBUILD_EXTMOD),) ifneq ($(srctree),.) -__hostc_flags = -I$(obj) $(call flags,_hostc_flags) -__hostcxx_flags = -I$(obj) $(call flags,_hostcxx_flags) +_hostc_flags += -I $(objtree)/$(obj) +_hostcxx_flags += -I $(objtree)/$(obj) endif endif -hostc_flags = -Wp,-MD,$(depfile) $(__hostc_flags) -hostcxx_flags = -Wp,-MD,$(depfile) $(__hostcxx_flags) +hostc_flags = -Wp,-MD,$(depfile) $(_hostc_flags) +hostcxx_flags = -Wp,-MD,$(depfile) $(_hostcxx_flags) ##### # Compile programs on the host diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib index 41e98fa66b91..1b412d4394ae 100644 --- a/scripts/Makefile.lib +++ b/scripts/Makefile.lib @@ -137,36 +137,26 @@ _c_flags += $(if $(patsubst n%,, \ $(CFLAGS_KCOV)) endif -__c_flags = $(_c_flags) -__a_flags = $(_a_flags) -__cpp_flags = $(_cpp_flags) - -# If building the kernel in a separate objtree expand all occurrences -# of -Idir to -I$(srctree)/dir except for absolute paths (starting with '/'). +# $(srctree)/$(src) for including checkin headers from generated source files +# $(objtree)/$(obj) for including generated headers from checkin source files ifeq ($(KBUILD_EXTMOD),) ifneq ($(srctree),.) - -# -I$(obj) locates generated .h files -# $(call addtree,-I$(obj)) locates .h files in srctree, from generated .c files -# and locates generated .h files -# FIXME: Replace both with specific CFLAGS* statements in the makefiles -__c_flags = $(if $(obj),$(call addtree,-I$(src)) -I$(obj)) \ - $(call flags,_c_flags) -__a_flags = $(call flags,_a_flags) -__cpp_flags = $(call flags,_cpp_flags) +_c_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj) +_a_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj) +_cpp_flags += -I $(srctree)/$(src) -I $(objtree)/$(obj) endif endif c_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ -include $(srctree)/include/linux/compiler_types.h \ - $(__c_flags) $(modkern_cflags) \ + $(_c_flags) $(modkern_cflags) \ $(basename_flags) $(modname_flags) a_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ - $(__a_flags) $(modkern_aflags) + $(_a_flags) $(modkern_aflags) cpp_flags = -Wp,-MD,$(depfile) $(NOSTDINC_FLAGS) $(LINUXINCLUDE) \ - $(__cpp_flags) + $(_cpp_flags) ld_flags = $(KBUILD_LDFLAGS) $(ldflags-y) $(LDFLAGS_$(@F)) -- 2.17.1
