linux/scripts/Makefile.host
Masahiro Yamada 42640b134b kbuild: move host .so build rules to scripts/gcc-plugins/Makefile
The host shared library rules are currently implemented in
scripts/Makefile.host, but actually GCC-plugin is the only user of
them. (The VDSO .so files are built for the target by different
build rules) Hence, they do not need to be treewide available.

Move all the relevant build rules to scripts/gcc-plugins/Makefile.

I also optimized the build steps so *.so is directly built from .c
because every upstream plugin is compiled from a single source file.

I am still keeping the multi-file plugin support, which Kees Cook
mentioned might be needed by out-of-tree plugins.
(https://lkml.org/lkml/2019/1/11/1107)

If the plugin, foo.so, is compiled from two files foo.c and foo2.c,
then you can do like follows:

  foo-objs := foo.o foo2.o

Single-file plugins do not need the *-objs notation.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Kees Cook <keescook@chromium.org>
2020-08-10 01:32:59 +09:00

135 lines
4.7 KiB
Makefile

# SPDX-License-Identifier: GPL-2.0
# LEX
# ---------------------------------------------------------------------------
quiet_cmd_flex = LEX $@
cmd_flex = $(LEX) -o$@ -L $<
$(obj)/%.lex.c: $(src)/%.l FORCE
$(call if_changed,flex)
# YACC
# ---------------------------------------------------------------------------
quiet_cmd_bison = YACC $(basename $@).[ch]
cmd_bison = $(YACC) -o $(basename $@).c --defines=$(basename $@).h -t -l $<
$(obj)/%.tab.c $(obj)/%.tab.h: $(src)/%.y FORCE
$(call if_changed,bison)
# ==========================================================================
# Building binaries on the host system
# Binaries are used during the compilation of the kernel, for example
# to preprocess a data file.
#
# Both C and C++ are supported, but preferred language is C for such utilities.
#
# Sample syntax (see Documentation/kbuild/makefiles.rst for reference)
# hostprogs := bin2hex
# Will compile bin2hex.c and create an executable named bin2hex
#
# hostprogs := lxdialog
# lxdialog-objs := checklist.o lxdialog.o
# Will compile lxdialog.c and checklist.c, and then link the executable
# lxdialog, based on checklist.o and lxdialog.o
#
# hostprogs := qconf
# qconf-cxxobjs := qconf.o
# qconf-objs := menu.o
# Will compile qconf as a C++ program, and menu as a C program.
# They are linked as C++ code to the executable qconf
__hostprogs := $(sort $(hostprogs))
# C code
# Executables compiled from a single .c file
host-csingle := $(foreach m,$(__hostprogs), \
$(if $($(m)-objs)$($(m)-cxxobjs),,$(m)))
# C executables linked based on several .o files
host-cmulti := $(foreach m,$(__hostprogs),\
$(if $($(m)-cxxobjs),,$(if $($(m)-objs),$(m))))
# Object (.o) files compiled from .c files
host-cobjs := $(sort $(foreach m,$(__hostprogs),$($(m)-objs)))
# C++ code
# C++ executables compiled from at least one .cc file
# and zero or more .c files
host-cxxmulti := $(foreach m,$(__hostprogs),$(if $($(m)-cxxobjs),$(m)))
# C++ Object (.o) files compiled from .cc files
host-cxxobjs := $(sort $(foreach m,$(host-cxxmulti),$($(m)-cxxobjs)))
host-csingle := $(addprefix $(obj)/,$(host-csingle))
host-cmulti := $(addprefix $(obj)/,$(host-cmulti))
host-cobjs := $(addprefix $(obj)/,$(host-cobjs))
host-cxxmulti := $(addprefix $(obj)/,$(host-cxxmulti))
host-cxxobjs := $(addprefix $(obj)/,$(host-cxxobjs))
#####
# Handle options to gcc. Support building with separate output directory
_hostc_flags = $(KBUILD_HOSTCFLAGS) $(HOST_EXTRACFLAGS) \
$(HOSTCFLAGS_$(target-stem).o)
_hostcxx_flags = $(KBUILD_HOSTCXXFLAGS) $(HOST_EXTRACXXFLAGS) \
$(HOSTCXXFLAGS_$(target-stem).o)
# $(objtree)/$(obj) for including generated headers from checkin source files
ifeq ($(KBUILD_EXTMOD),)
ifdef building_out_of_srctree
_hostc_flags += -I $(objtree)/$(obj)
_hostcxx_flags += -I $(objtree)/$(obj)
endif
endif
hostc_flags = -Wp,-MMD,$(depfile) $(_hostc_flags)
hostcxx_flags = -Wp,-MMD,$(depfile) $(_hostcxx_flags)
#####
# Compile programs on the host
# Create executable from a single .c file
# host-csingle -> Executable
quiet_cmd_host-csingle = HOSTCC $@
cmd_host-csingle = $(HOSTCC) $(hostc_flags) $(KBUILD_HOSTLDFLAGS) -o $@ $< \
$(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(target-stem))
$(host-csingle): $(obj)/%: $(src)/%.c FORCE
$(call if_changed_dep,host-csingle)
# Link an executable based on list of .o files, all plain c
# host-cmulti -> executable
quiet_cmd_host-cmulti = HOSTLD $@
cmd_host-cmulti = $(HOSTCC) $(KBUILD_HOSTLDFLAGS) -o $@ \
$(addprefix $(obj)/, $($(target-stem)-objs)) \
$(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(target-stem))
$(host-cmulti): FORCE
$(call if_changed,host-cmulti)
$(call multi_depend, $(host-cmulti), , -objs)
# Create .o file from a single .c file
# host-cobjs -> .o
quiet_cmd_host-cobjs = HOSTCC $@
cmd_host-cobjs = $(HOSTCC) $(hostc_flags) -c -o $@ $<
$(host-cobjs): $(obj)/%.o: $(src)/%.c FORCE
$(call if_changed_dep,host-cobjs)
# Link an executable based on list of .o files, a mixture of .c and .cc
# host-cxxmulti -> executable
quiet_cmd_host-cxxmulti = HOSTLD $@
cmd_host-cxxmulti = $(HOSTCXX) $(KBUILD_HOSTLDFLAGS) -o $@ \
$(foreach o,objs cxxobjs,\
$(addprefix $(obj)/, $($(target-stem)-$(o)))) \
$(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(target-stem))
$(host-cxxmulti): FORCE
$(call if_changed,host-cxxmulti)
$(call multi_depend, $(host-cxxmulti), , -objs -cxxobjs)
# Create .o file from a single .cc (C++) file
quiet_cmd_host-cxxobjs = HOSTCXX $@
cmd_host-cxxobjs = $(HOSTCXX) $(hostcxx_flags) -c -o $@ $<
$(host-cxxobjs): $(obj)/%.o: $(src)/%.cc FORCE
$(call if_changed_dep,host-cxxobjs)
targets += $(host-csingle) $(host-cmulti) $(host-cobjs) \
$(host-cxxmulti) $(host-cxxobjs)