# SPDX-License-Identifier: GPL-2.0
# ==========================================================================
# 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.txt for reference)
# hostprogs-y := bin2hex
# Will compile bin2hex.c and create an executable named bin2hex
#
# hostprogs-y := 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-y := 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-y) $(hostprogs-m))
host-cshlib := $(sort $(hostlibs-y) $(hostlibs-m))
host-cxxshlib := $(sort $(hostcxxlibs-y) $(hostcxxlibs-m))
# 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)))
# Object (.o) files used by the shared libaries
host-cshobjs := $(sort $(foreach m,$(host-cshlib),$($(m:.so=-objs))))
host-cxxshobjs := $(sort $(foreach m,$(host-cxxshlib),$($(m:.so=-objs))))
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))
host-cshlib := $(addprefix $(obj)/,$(host-cshlib))
host-cxxshlib := $(addprefix $(obj)/,$(host-cxxshlib))
host-cshobjs := $(addprefix $(obj)/,$(host-cshobjs))
host-cxxshobjs := $(addprefix $(obj)/,$(host-cxxshobjs))
#####
# 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)
ifeq ($(KBUILD_SRC),)
__hostc_flags = $(_hostc_flags)
__hostcxx_flags = $(_hostcxx_flags)
else
__hostc_flags = -I$(obj) $(call flags,_hostc_flags)
__hostcxx_flags = -I$(obj) $(call flags,_hostcxx_flags)
endif
hostc_flags = -Wp,-MD,$(depfile) $(__hostc_flags)
hostcxx_flags = -Wp,-MD,$(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)
# Compile .c file, create position independent .o file
# host-cshobjs -> .o
quiet_cmd_host-cshobjs = HOSTCC -fPIC $@
cmd_host-cshobjs = $(HOSTCC) $(hostc_flags) -fPIC -c -o $@ $<
$(host-cshobjs): $(obj)/%.o: $(src)/%.c FORCE
$(call if_changed_dep,host-cshobjs)
# Compile .c file, create position independent .o file
# Note that plugin capable gcc versions can be either C or C++ based
# therefore plugin source files have to be compilable in both C and C++ mode.
# This is why a C++ compiler is invoked on a .c file.
# host-cxxshobjs -> .o
quiet_cmd_host-cxxshobjs = HOSTCXX -fPIC $@
cmd_host-cxxshobjs = $(HOSTCXX) $(hostcxx_flags) -fPIC -c -o $@ $<
$(host-cxxshobjs): $(obj)/%.o: $(src)/%.c FORCE
$(call if_changed_dep,host-cxxshobjs)
# Link a shared library, based on position independent .o files
# *.o -> .so shared library (host-cshlib)
quiet_cmd_host-cshlib = HOSTLLD -shared $@
cmd_host-cshlib = $(HOSTCC) $(KBUILD_HOSTLDFLAGS) -shared -o $@ \
$(addprefix $(obj)/, $($(target-stem)-objs)) \
$(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(target-stem).so)
$(host-cshlib): FORCE
$(call if_changed,host-cshlib)
$(call multi_depend, $(host-cshlib), .so, -objs)
# Link a shared library, based on position independent .o files
# *.o -> .so shared library (host-cxxshlib)
quiet_cmd_host-cxxshlib = HOSTLLD -shared $@
cmd_host-cxxshlib = $(HOSTCXX) $(KBUILD_HOSTLDFLAGS) -shared -o $@ \
$(addprefix $(obj)/, $($(target-stem)-objs)) \
$(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(target-stem).so)
$(host-cxxshlib): FORCE
$(call if_changed,host-cxxshlib)
$(call multi_depend, $(host-cxxshlib), .so, -objs)
targets += $(host-csingle) $(host-cmulti) $(host-cobjs)\
$(host-cxxmulti) $(host-cxxobjs) $(host-cshlib) $(host-cshobjs) $(host-cxxshlib) $(host-cxxshobjs)
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