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)) 25host-cshlib := $(sort $(hostlibs-y) $(hostlibs-m)) 26host-cxxshlib := $(sort $(hostcxxlibs-y) $(hostcxxlibs-m)) 27 28# C code 29# Executables compiled from a single .c file 30host-csingle := $(foreach m,$(__hostprogs), \ 31 $(if $($(m)-objs)$($(m)-cxxobjs)$($(m)-sharedobjs),,$(m))) 32 33# C executables linked based on several .o files 34host-cmulti := $(foreach m,$(__hostprogs),\ 35 $(if $($(m)-cxxobjs),,$(if $($(m)-objs),$(m)))) 36 37# Shared object libraries 38host-shared := $(foreach m,$(__hostprogs),\ 39 $(if $($(m)-sharedobjs),$(m)))) 40 41# Object (.o) files compiled from .c files 42host-cobjs := $(sort $(foreach m,$(__hostprogs),$($(m)-objs))) 43 44# C++ code 45# C++ executables compiled from at least one .cc file 46# and zero or more .c files 47host-cxxmulti := $(foreach m,$(__hostprogs),$(if $($(m)-cxxobjs),$(m))) 48 49# C++ Object (.o) files compiled from .cc files 50host-cxxobjs := $(sort $(foreach m,$(host-cxxmulti),$($(m)-cxxobjs))) 51 52# Object (.o) files used by the shared libaries 53host-cshobjs := $(sort $(foreach m,$(host-cshlib),$($(m:.so=-objs)))) 54host-cxxshobjs := $(sort $(foreach m,$(host-cxxshlib),$($(m:.so=-objs)))) 55 56host-csingle := $(addprefix $(obj)/,$(host-csingle)) 57host-cmulti := $(addprefix $(obj)/,$(host-cmulti)) 58host-cobjs := $(addprefix $(obj)/,$(host-cobjs)) 59host-cxxmulti := $(addprefix $(obj)/,$(host-cxxmulti)) 60host-cxxobjs := $(addprefix $(obj)/,$(host-cxxobjs)) 61host-cshlib := $(addprefix $(obj)/,$(host-cshlib)) 62host-cxxshlib := $(addprefix $(obj)/,$(host-cxxshlib)) 63host-cshobjs := $(addprefix $(obj)/,$(host-cshobjs)) 64host-cxxshobjs := $(addprefix $(obj)/,$(host-cxxshobjs)) 65host-shared := $(addprefix $(obj)/,$(host-shared)) 66 67##### 68# Handle options to gcc. Support building with separate output directory 69 70_hostc_flags = $(KBUILD_HOSTCFLAGS) $(HOST_EXTRACFLAGS) \ 71 $(HOSTCFLAGS_$(basetarget).o) 72_hostcxx_flags = $(KBUILD_HOSTCXXFLAGS) $(HOST_EXTRACXXFLAGS) \ 73 $(HOSTCXXFLAGS_$(basetarget).o) 74 75ifeq ($(KBUILD_SRC),) 76__hostc_flags = $(_hostc_flags) 77__hostcxx_flags = $(_hostcxx_flags) 78else 79__hostc_flags = -I$(obj) $(call flags,_hostc_flags) 80__hostcxx_flags = -I$(obj) $(call flags,_hostcxx_flags) 81endif 82 83hostc_flags = -Wp,-MD,$(depfile) $(__hostc_flags) 84hostcxx_flags = -Wp,-MD,$(depfile) $(__hostcxx_flags) 85 86##### 87# Compile programs on the host 88 89# Create executable from a single .c file 90# host-csingle -> Executable 91quiet_cmd_host-csingle = HOSTCC $@ 92 cmd_host-csingle = $(HOSTCC) $(hostc_flags) -o $@ $< \ 93 $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(@F)) 94$(host-csingle): $(obj)/%: $(src)/%.c FORCE 95 $(call if_changed_dep,host-csingle) 96 97# Link an executable based on list of .o files, all plain c 98# host-cmulti -> executable 99quiet_cmd_host-cmulti = HOSTLD $@ 100 cmd_host-cmulti = $(HOSTCC) $(KBUILD_HOSTLDFLAGS) -o $@ \ 101 $(addprefix $(obj)/,$($(@F)-objs)) \ 102 $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(@F)) 103$(host-cmulti): FORCE 104 $(call if_changed,host-cmulti) 105$(call multi_depend, $(host-cmulti), , -objs) 106 107# Create .o file from a single .c file 108# host-cobjs -> .o 109quiet_cmd_host-cobjs = HOSTCC $@ 110 cmd_host-cobjs = $(HOSTCC) $(hostc_flags) -c -o $@ $< 111$(host-cobjs): $(obj)/%.o: $(src)/%.c FORCE 112 $(call if_changed_dep,host-cobjs) 113 114# Link an executable based on list of .o files, a mixture of .c and .cc 115# host-cxxmulti -> executable 116quiet_cmd_host-cxxmulti = HOSTLD $@ 117 cmd_host-cxxmulti = $(HOSTCXX) $(KBUILD_HOSTLDFLAGS) -o $@ \ 118 $(foreach o,objs cxxobjs,\ 119 $(addprefix $(obj)/,$($(@F)-$(o)))) \ 120 $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(@F)) 121$(host-cxxmulti): FORCE 122 $(call if_changed,host-cxxmulti) 123$(call multi_depend, $(host-cxxmulti), , -objs -cxxobjs) 124 125# Create .o file from a single .cc (C++) file 126quiet_cmd_host-cxxobjs = HOSTCXX $@ 127 cmd_host-cxxobjs = $(HOSTCXX) $(hostcxx_flags) -c -o $@ $< 128$(host-cxxobjs): $(obj)/%.o: $(src)/%.cc FORCE 129 $(call if_changed_dep,host-cxxobjs) 130 131# Compile .c file, create position independent .o file 132# host-cshobjs -> .o 133quiet_cmd_host-cshobjs = HOSTCC -fPIC $@ 134 cmd_host-cshobjs = $(HOSTCC) $(hostc_flags) -fPIC -c -o $@ $< 135$(host-cshobjs): $(obj)/%.o: $(src)/%.c FORCE 136 $(call if_changed_dep,host-cshobjs) 137 138# Compile .c file, create position independent .o file 139# Note that plugin capable gcc versions can be either C or C++ based 140# therefore plugin source files have to be compilable in both C and C++ mode. 141# This is why a C++ compiler is invoked on a .c file. 142# host-cxxshobjs -> .o 143quiet_cmd_host-cxxshobjs = HOSTCXX -fPIC $@ 144 cmd_host-cxxshobjs = $(HOSTCXX) $(hostcxx_flags) -fPIC -c -o $@ $< 145$(host-cxxshobjs): $(obj)/%.o: $(src)/%.c FORCE 146 $(call if_changed_dep,host-cxxshobjs) 147 148# Link a shared library, based on position independent .o files 149# *.o -> .so shared library (host-cshlib) 150quiet_cmd_host-cshlib = HOSTLLD -shared $@ 151 cmd_host-cshlib = $(HOSTCC) $(HOSTLDFLAGS) -shared -o $@ \ 152 $(addprefix $(obj)/,$($(@F:.so=-objs))) \ 153 $(HOST_LOADLIBES) $(HOSTLDLIBS_$(@F)) 154$(host-cshlib): FORCE 155 $(call if_changed,host-cshlib) 156$(call multi_depend, $(host-cshlib), .so, -objs) 157 158# Link a shared library, based on position independent .o files 159# *.o -> .so shared library (host-cxxshlib) 160quiet_cmd_host-cxxshlib = HOSTLLD -shared $@ 161 cmd_host-cxxshlib = $(HOSTCXX) $(HOSTLDFLAGS) -shared -o $@ \ 162 $(addprefix $(obj)/,$($(@F:.so=-objs))) \ 163 $(HOST_LOADLIBES) $(HOSTLDLIBS_$(@F)) 164$(host-cxxshlib): FORCE 165 $(call if_changed,host-cxxshlib) 166$(call multi_depend, $(host-cxxshlib), .so, -objs) 167 168targets += $(host-csingle) $(host-cmulti) $(host-cobjs)\ 169 $(host-cxxmulti) $(host-cxxobjs) $(host-shared) \ 170 $(host-cshlib) $(host-cshobjs) $(host-cxxshlib) $(host-cxxshobjs) 171