1# SPDX-License-Identifier: GPL-2.0 2# ========================================================================== 3# Building binaries on the host system 4# Binaries are used during the compilation of the kernel, for example 5# to preprocess a data file. 6# 7# Both C and C++ are supported, but preferred language is C for such utilities. 8# 9# Sample syntax (see Documentation/kbuild/makefiles.txt for reference) 10# hostprogs-y := bin2hex 11# Will compile bin2hex.c and create an executable named bin2hex 12# 13# hostprogs-y := lxdialog 14# lxdialog-objs := checklist.o lxdialog.o 15# Will compile lxdialog.c and checklist.c, and then link the executable 16# lxdialog, based on checklist.o and lxdialog.o 17# 18# hostprogs-y := qconf 19# qconf-cxxobjs := qconf.o 20# qconf-objs := menu.o 21# Will compile qconf as a C++ program, and menu as a C program. 22# They are linked as C++ code to the executable qconf 23 24__hostprogs := $(sort $(hostprogs-y) $(hostprogs-m)) 25 26# C code 27# Executables compiled from a single .c file 28host-csingle := $(foreach m,$(__hostprogs), \ 29 $(if $($(m)-objs)$($(m)-cxxobjs)$($(m)-sharedobjs),,$(m))) 30 31# C executables linked based on several .o files 32host-cmulti := $(foreach m,$(__hostprogs),\ 33 $(if $($(m)-cxxobjs),,$(if $($(m)-objs),$(m)))) 34 35# Shared object libraries 36host-shared := $(foreach m,$(__hostprogs),\ 37 $(if $($(m)-sharedobjs),$(m)))) 38 39# Object (.o) files compiled from .c files 40host-cobjs := $(sort $(foreach m,$(__hostprogs),$($(m)-objs))) 41 42# C++ code 43# C++ executables compiled from at least one .cc file 44# and zero or more .c files 45host-cxxmulti := $(foreach m,$(__hostprogs),$(if $($(m)-cxxobjs),$(m))) 46 47# C++ Object (.o) files compiled from .cc files 48host-cxxobjs := $(sort $(foreach m,$(host-cxxmulti),$($(m)-cxxobjs))) 49 50# output directory for programs/.o files 51# hostprogs-y := tools/build may have been specified. 52# Retrieve also directory of .o files from prog-objs or prog-cxxobjs notation 53host-objdirs := $(dir $(__hostprogs) $(host-cobjs) $(host-cxxobjs)) 54 55host-objdirs := $(strip $(sort $(filter-out ./,$(host-objdirs)))) 56 57 58__hostprogs := $(addprefix $(obj)/,$(__hostprogs)) 59host-csingle := $(addprefix $(obj)/,$(host-csingle)) 60host-cmulti := $(addprefix $(obj)/,$(host-cmulti)) 61host-cobjs := $(addprefix $(obj)/,$(host-cobjs)) 62host-cxxmulti := $(addprefix $(obj)/,$(host-cxxmulti)) 63host-cxxobjs := $(addprefix $(obj)/,$(host-cxxobjs)) 64host-shared := $(addprefix $(obj)/,$(host-shared)) 65host-objdirs := $(addprefix $(obj)/,$(host-objdirs)) 66 67obj-dirs += $(host-objdirs) 68 69##### 70# Handle options to gcc. Support building with separate output directory 71 72_hostc_flags = $(HOSTCFLAGS) $(HOST_EXTRACFLAGS) \ 73 $(HOSTCFLAGS_$(basetarget).o) 74_hostcxx_flags = $(HOSTCXXFLAGS) $(HOST_EXTRACXXFLAGS) \ 75 $(HOSTCXXFLAGS_$(basetarget).o) 76 77ifeq ($(KBUILD_SRC),) 78__hostc_flags = $(_hostc_flags) 79__hostcxx_flags = $(_hostcxx_flags) 80else 81__hostc_flags = -I$(obj) $(call flags,_hostc_flags) 82__hostcxx_flags = -I$(obj) $(call flags,_hostcxx_flags) 83endif 84 85hostc_flags = -Wp,-MD,$(depfile) $(__hostc_flags) 86hostcxx_flags = -Wp,-MD,$(depfile) $(__hostcxx_flags) 87 88##### 89# Compile programs on the host 90 91# Create executable from a single .c file 92# host-csingle -> Executable 93quiet_cmd_host-csingle = HOSTCC $@ 94 cmd_host-csingle = $(HOSTCC) $(hostc_flags) -o $@ $< \ 95 $(HOST_LOADLIBES) $(HOSTLOADLIBES_$(@F)) 96$(host-csingle): $(obj)/%: $(src)/%.c FORCE 97 $(call if_changed_dep,host-csingle) 98 99# Link an executable based on list of .o files, all plain c 100# host-cmulti -> executable 101quiet_cmd_host-cmulti = HOSTLD $@ 102 cmd_host-cmulti = $(HOSTCC) $(HOSTLDFLAGS) -o $@ \ 103 $(addprefix $(obj)/,$($(@F)-objs)) \ 104 $(HOST_LOADLIBES) $(HOSTLOADLIBES_$(@F)) 105$(host-cmulti): FORCE 106 $(call if_changed,host-cmulti) 107$(call multi_depend, $(host-cmulti), , -objs) 108 109# Create .o file from a single .c file 110# host-cobjs -> .o 111quiet_cmd_host-cobjs = HOSTCC $@ 112 cmd_host-cobjs = $(HOSTCC) $(hostc_flags) -c -o $@ $< 113$(host-cobjs): $(obj)/%.o: $(src)/%.c FORCE 114 $(call if_changed_dep,host-cobjs) 115 116# Link an executable based on list of .o files, a mixture of .c and .cc 117# host-cxxmulti -> executable 118quiet_cmd_host-cxxmulti = HOSTLD $@ 119 cmd_host-cxxmulti = $(HOSTCXX) $(HOSTLDFLAGS) -o $@ \ 120 $(foreach o,objs cxxobjs,\ 121 $(addprefix $(obj)/,$($(@F)-$(o)))) \ 122 $(HOST_LOADLIBES) $(HOSTLOADLIBES_$(@F)) 123$(host-cxxmulti): FORCE 124 $(call if_changed,host-cxxmulti) 125$(call multi_depend, $(host-cxxmulti), , -objs -cxxobjs) 126 127# Create .o file from a single .cc (C++) file 128quiet_cmd_host-cxxobjs = HOSTCXX $@ 129 cmd_host-cxxobjs = $(HOSTCXX) $(hostcxx_flags) -c -o $@ $< 130$(host-cxxobjs): $(obj)/%.o: $(src)/%.cc FORCE 131 $(call if_changed_dep,host-cxxobjs) 132 133targets += $(host-csingle) $(host-cmulti) $(host-cobjs)\ 134 $(host-cxxmulti) $(host-cxxobjs) $(host-shared) 135