Kbuild provides per-file compiler flag addition/removal:
CFLAGS_<basetarget>.o
CFLAGS_REMOVE_<basetarget>.o
AFLAGS_<basetarget>.o
AFLAGS_REMOVE_<basetarget>.o
CPPFLAGS_<basetarget>
HOSTCFLAGS_<basetarget>.o
HOSTCXXFLAGS_<basetarget>.o
The <basetarget> is the filename of the target without its suffix.
This syntax comes into a trouble when two files with the same name
appear in one Makefile, for example:
obj-y += foo.o
obj-y += dir/foo.o
CFLAGS_foo.o := <some-flags>
Here, the <some-flags> applies to both foo.o and dir/foo.o
The real world problem is:
scripts/kconfig/util.c
scripts/kconfig/lxdialog/util.c
Both files are compiled into scripts/kconfig/mconf, but only the
latter should be given with additional flags for ncurses.
It is more sensible to use the relative path to the Makefile, like this:
obj-y += foo.o
CFLAGS_foo.o := <some-flags>
obj-y += dir/foo.o
CFLAGS_dir/foo.o := <other-flags>
The $* variable is replaced with the stem ('%') part in a pattern rule.
In other words, this only works for pattern rules.
Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx>
---
arch/arm/kvm/Makefile | 5 +++--
arch/x86/entry/vdso/Makefile | 3 ++-
scripts/Makefile.host | 30 +++++++++++++++---------------
scripts/Makefile.lib | 10 +++++-----
scripts/kconfig/Makefile | 8 ++++----
5 files changed, 29 insertions(+), 27 deletions(-)
diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile
index 531e59f5be9c..b76b75bd9e00 100644
--- a/arch/arm/kvm/Makefile
+++ b/arch/arm/kvm/Makefile
@@ -8,13 +8,14 @@ ifeq ($(plus_virt),+virt)
plus_virt_def := -DREQUIRES_VIRT=1
endif
+KVM := ../../../virt/kvm
+
ccflags-y += -I $(srctree)/$(src) -I $(srctree)/virt/kvm/arm/vgic
-CFLAGS_arm.o := $(plus_virt_def)
+CFLAGS_$(KVM)/arm/arm.o := $(plus_virt_def)
AFLAGS_init.o := -Wa,-march=armv7-a$(plus_virt)
AFLAGS_interrupts.o := -Wa,-march=armv7-a$(plus_virt)
-KVM := ../../../virt/kvm
kvm-arm-y = $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o $(KVM)/vfio.o
obj-$(CONFIG_KVM_ARM_HOST) += hyp/
diff --git a/arch/x86/entry/vdso/Makefile b/arch/x86/entry/vdso/Makefile
index 8df549138193..0f2154106d01 100644
--- a/arch/x86/entry/vdso/Makefile
+++ b/arch/x86/entry/vdso/Makefile
@@ -89,6 +89,7 @@ $(vobjs): KBUILD_CFLAGS := $(filter-out $(GCC_PLUGINS_CFLAGS) $(RETPOLINE_CFLAGS
#
CFLAGS_REMOVE_vdso-note.o = -pg
CFLAGS_REMOVE_vclock_gettime.o = -pg
+CFLAGS_REMOVE_vdso32/vclock_gettime.o = -pg
CFLAGS_REMOVE_vgetcpu.o = -pg
CFLAGS_REMOVE_vvar.o = -pg
@@ -128,7 +129,7 @@ $(obj)/%.so: $(obj)/%.so.dbg FORCE
$(obj)/vdsox32.so.dbg: $(obj)/vdsox32.lds $(vobjx32s) FORCE
$(call if_changed,vdso_and_check)
-CPPFLAGS_vdso32.lds = $(CPPFLAGS_vdso.lds)
+CPPFLAGS_vdso32/vdso32.lds = $(CPPFLAGS_vdso.lds)
VDSO_LDFLAGS_vdso32.lds = -m elf_i386 -soname linux-gate.so.1
targets += vdso32/vdso32.lds
diff --git a/scripts/Makefile.host b/scripts/Makefile.host
index b402c619147d..cd2b98e2f727 100644
--- a/scripts/Makefile.host
+++ b/scripts/Makefile.host
@@ -80,9 +80,9 @@ host-cxxshobjs := $(addprefix $(obj)/,$(host-cxxshobjs))
# Handle options to gcc. Support building with separate output directory
_hostc_flags = $(KBUILD_HOSTCFLAGS) $(HOST_EXTRACFLAGS) \
- $(HOSTCFLAGS_$(basetarget).o)
+ $(HOSTCFLAGS_$*.o)
_hostcxx_flags = $(KBUILD_HOSTCXXFLAGS) $(HOST_EXTRACXXFLAGS) \
- $(HOSTCXXFLAGS_$(basetarget).o)
+ $(HOSTCXXFLAGS_$*.o)
# $(objtree)/$(obj) for including generated headers from checkin source files
ifeq ($(KBUILD_EXTMOD),)
@@ -102,7 +102,7 @@ hostcxx_flags = -Wp,-MD,$(depfile) $(_hostcxx_flags)
# host-csingle -> Executable
quiet_cmd_host-csingle = HOSTCC $@
cmd_host-csingle = $(HOSTCC) $(hostc_flags) $(KBUILD_HOSTLDFLAGS) -o $@ $< \
- $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(@F))
+ $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$*)
$(host-csingle): $(obj)/%: $(src)/%.c FORCE
$(call if_changed_dep,host-csingle)
@@ -110,9 +110,9 @@ $(host-csingle): $(obj)/%: $(src)/%.c FORCE
# host-cmulti -> executable
quiet_cmd_host-cmulti = HOSTLD $@
cmd_host-cmulti = $(HOSTCC) $(KBUILD_HOSTLDFLAGS) -o $@ \
- $(addprefix $(obj)/,$($(@F)-objs)) \
- $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(@F))
-$(host-cmulti): FORCE
+ $(addprefix $(obj)/, $($*-objs)) \
+ $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$*)
+$(host-cmulti): $(obj)/%: FORCE
$(call if_changed,host-cmulti)
$(call multi_depend, $(host-cmulti), , -objs)
@@ -128,9 +128,9 @@ $(host-cobjs): $(obj)/%.o: $(src)/%.c FORCE
quiet_cmd_host-cxxmulti = HOSTLD $@
cmd_host-cxxmulti = $(HOSTCXX) $(KBUILD_HOSTLDFLAGS) -o $@ \
$(foreach o,objs cxxobjs,\
- $(addprefix $(obj)/,$($(@F)-$(o)))) \
- $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(@F))
-$(host-cxxmulti): FORCE
+ $(addprefix $(obj)/, $($*-$(o)))) \
+ $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$*)
+$(host-cxxmulti): $(obj)/%: FORCE
$(call if_changed,host-cxxmulti)
$(call multi_depend, $(host-cxxmulti), , -objs -cxxobjs)
@@ -161,9 +161,9 @@ $(host-cxxshobjs): $(obj)/%.o: $(src)/%.c FORCE
# *.o -> .so shared library (host-cshlib)
quiet_cmd_host-cshlib = HOSTLLD -shared $@
cmd_host-cshlib = $(HOSTCC) $(KBUILD_HOSTLDFLAGS) -shared -o $@ \
- $(addprefix $(obj)/,$($(@F:.so=-objs))) \
- $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(@F))
-$(host-cshlib): FORCE
+ $(addprefix $(obj)/, $($*-objs)) \
+ $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$*.so)
+$(host-cshlib): $(obj)/%.so: FORCE
$(call if_changed,host-cshlib)
$(call multi_depend, $(host-cshlib), .so, -objs)
@@ -171,9 +171,9 @@ $(call multi_depend, $(host-cshlib), .so, -objs)
# *.o -> .so shared library (host-cxxshlib)
quiet_cmd_host-cxxshlib = HOSTLLD -shared $@
cmd_host-cxxshlib = $(HOSTCXX) $(KBUILD_HOSTLDFLAGS) -shared -o $@ \
- $(addprefix $(obj)/,$($(@F:.so=-objs))) \
- $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(@F))
-$(host-cxxshlib): FORCE
+ $(addprefix $(obj)/, $($*-objs)) \
+ $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$*.so)
+$(host-cxxshlib): $(obj)/%.so: FORCE
$(call if_changed,host-cxxshlib)
$(call multi_depend, $(host-cxxshlib), .so, -objs)
diff --git a/scripts/Makefile.lib b/scripts/Makefile.lib
index 264611972c4a..0d48e17bfb07 100644
--- a/scripts/Makefile.lib
+++ b/scripts/Makefile.lib
@@ -109,12 +109,12 @@ basename_flags = -DKBUILD_BASENAME=$(call name-fix,$(basetarget))
modname_flags = -DKBUILD_MODNAME=$(call name-fix,$(modname))
orig_c_flags = $(KBUILD_CPPFLAGS) $(KBUILD_CFLAGS) \
- $(ccflags-y) $(CFLAGS_$(basetarget).o)
-_c_flags = $(filter-out $(CFLAGS_REMOVE_$(basetarget).o), $(orig_c_flags))
+ $(ccflags-y) $(CFLAGS_$*.o)
+_c_flags = $(filter-out $(CFLAGS_REMOVE_$*.o), $(orig_c_flags))
orig_a_flags = $(KBUILD_CPPFLAGS) $(KBUILD_AFLAGS) \
- $(asflags-y) $(AFLAGS_$(basetarget).o)
-_a_flags = $(filter-out $(AFLAGS_REMOVE_$(basetarget).o), $(orig_a_flags))
-_cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$(@F))
+ $(asflags-y) $(AFLAGS_$*.o)
+_a_flags = $(filter-out $(AFLAGS_REMOVE_$*.o), $(orig_a_flags))
+_cpp_flags = $(KBUILD_CPPFLAGS) $(cppflags-y) $(CPPFLAGS_$*.lds)
#
# Enable gcov profiling flags for a file, directory or for all files depending
diff --git a/scripts/kconfig/Makefile b/scripts/kconfig/Makefile
index bed7a5a2fbe9..ef2f2336c469 100644
--- a/scripts/kconfig/Makefile
+++ b/scripts/kconfig/Makefile
@@ -166,15 +166,15 @@ $(obj)/nconf.o $(obj)/nconf.gui.o: $(obj)/nconf-cfg
# mconf: Used for the menuconfig target based on lxdialog
hostprogs-y += mconf
-lxdialog := checklist.o inputbox.o menubox.o textbox.o util.o yesno.o
-mconf-objs := mconf.o $(addprefix lxdialog/, $(lxdialog)) $(common-objs)
+lxdialog := $(addprefix lxdialog/, \
+ checklist.o inputbox.o menubox.o textbox.o util.o yesno.o)
+mconf-objs := mconf.o $(lxdialog) $(common-objs)
HOSTLDLIBS_mconf = $(shell . $(obj)/mconf-cfg && echo $$libs)
$(foreach f, mconf.o $(lxdialog), \
$(eval HOSTCFLAGS_$f = $$(shell . $(obj)/mconf-cfg && echo $$$$cflags)))
-$(obj)/mconf.o: $(obj)/mconf-cfg
-$(addprefix $(obj)/lxdialog/, $(lxdialog)): $(obj)/mconf-cfg
+$(addprefix $(obj)/, mconf.o $(lxdialog)): $(obj)/mconf-cfg
# qconf: Used for the xconfig target based on Qt
hostprogs-y += qconf
--
2.17.1
