1 # SPDX-License-Identifier: GPL-2.0
4 # ---------------------------------------------------------------------------
5 quiet_cmd_flex = LEX $@
6 cmd_flex = $(LEX) -o$@ -L $<
8 $(obj)/%.lex.c: $(src)/%.l FORCE
9 $(call if_changed,flex)
12 # ---------------------------------------------------------------------------
13 quiet_cmd_bison = YACC $(basename $@).[ch]
14 cmd_bison = $(YACC) -o $(basename $@).c --defines=$(basename $@).h -t -l $<
16 $(obj)/%.tab.c $(obj)/%.tab.h: $(src)/%.y FORCE
17 $(call if_changed,bison)
19 # ==========================================================================
20 # Building binaries on the host system
21 # Binaries are used during the compilation of the kernel, for example
22 # to preprocess a data file.
24 # Both C and C++ are supported, but preferred language is C for such utilities.
25 # Rust is also supported, but it may only be used in scenarios where a Rust
26 # toolchain is required to be available (e.g. when `CONFIG_RUST` is enabled).
28 # Sample syntax (see Documentation/kbuild/makefiles.rst for reference)
29 # hostprogs := bin2hex
30 # Will compile bin2hex.c and create an executable named bin2hex
32 # hostprogs := lxdialog
33 # lxdialog-objs := checklist.o lxdialog.o
34 # Will compile lxdialog.c and checklist.c, and then link the executable
35 # lxdialog, based on checklist.o and lxdialog.o
38 # qconf-cxxobjs := qconf.o
39 # qconf-objs := menu.o
40 # Will compile qconf as a C++ program, and menu as a C program.
41 # They are linked as C++ code to the executable qconf
45 # Will compile `target` as a Rust program, using `target.rs` as the crate root.
46 # The crate may consist of several source files.
49 # Executables compiled from a single .c file
50 host-csingle := $(foreach m,$(hostprogs), \
51 $(if $($(m)-objs)$($(m)-cxxobjs)$($(m)-rust),,$(m)))
53 # C executables linked based on several .o files
54 host-cmulti := $(foreach m,$(hostprogs),\
55 $(if $($(m)-cxxobjs)$($(m)-rust),,$(if $($(m)-objs),$(m))))
57 # Object (.o) files compiled from .c files
58 host-cobjs := $(sort $(foreach m,$(hostprogs),$($(m)-objs)))
61 # C++ executables compiled from at least one .cc file
62 # and zero or more .c files
63 host-cxxmulti := $(foreach m,$(hostprogs),$(if $($(m)-cxxobjs),$(m)))
65 # C++ Object (.o) files compiled from .cc files
66 host-cxxobjs := $(sort $(foreach m,$(host-cxxmulti),$($(m)-cxxobjs)))
69 # Executables compiled from a single Rust crate (which may consist of
70 # one or more .rs files)
71 host-rust := $(foreach m,$(hostprogs),$(if $($(m)-rust),$(m)))
73 host-csingle := $(addprefix $(obj)/,$(host-csingle))
74 host-cmulti := $(addprefix $(obj)/,$(host-cmulti))
75 host-cobjs := $(addprefix $(obj)/,$(host-cobjs))
76 host-cxxmulti := $(addprefix $(obj)/,$(host-cxxmulti))
77 host-cxxobjs := $(addprefix $(obj)/,$(host-cxxobjs))
78 host-rust := $(addprefix $(obj)/,$(host-rust))
81 # Handle options to gcc. Support building with separate output directory
83 hostc_flags = -Wp,-MMD,$(depfile) \
84 $(KBUILD_HOSTCFLAGS) $(HOST_EXTRACFLAGS) \
85 $(HOSTCFLAGS_$(target-stem).o)
86 hostcxx_flags = -Wp,-MMD,$(depfile) \
87 $(KBUILD_HOSTCXXFLAGS) $(HOST_EXTRACXXFLAGS) \
88 $(HOSTCXXFLAGS_$(target-stem).o)
90 # `--out-dir` is required to avoid temporaries being created by `rustc` in the
91 # current working directory, which may be not accessible in the out-of-tree
93 hostrust_flags = --out-dir $(dir $@) --emit=dep-info=$(depfile) \
94 $(KBUILD_HOSTRUSTFLAGS) $(HOST_EXTRARUSTFLAGS) \
95 $(HOSTRUSTFLAGS_$(target-stem))
97 # $(objtree)/$(obj) for including generated headers from checkin source files
98 ifeq ($(KBUILD_EXTMOD),)
99 ifdef building_out_of_srctree
100 hostc_flags += -I $(objtree)/$(obj)
101 hostcxx_flags += -I $(objtree)/$(obj)
106 # Compile programs on the host
108 # Create executable from a single .c file
109 # host-csingle -> Executable
110 quiet_cmd_host-csingle = HOSTCC $@
111 cmd_host-csingle = $(HOSTCC) $(hostc_flags) $(KBUILD_HOSTLDFLAGS) -o $@ $< \
112 $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(target-stem))
113 $(host-csingle): $(obj)/%: $(src)/%.c FORCE
114 $(call if_changed_dep,host-csingle)
116 # Link an executable based on list of .o files, all plain c
117 # host-cmulti -> executable
118 quiet_cmd_host-cmulti = HOSTLD $@
119 cmd_host-cmulti = $(HOSTCC) $(KBUILD_HOSTLDFLAGS) -o $@ \
120 $(addprefix $(obj)/, $($(target-stem)-objs)) \
121 $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(target-stem))
122 $(host-cmulti): FORCE
123 $(call if_changed,host-cmulti)
124 $(call multi_depend, $(host-cmulti), , -objs)
126 # Create .o file from a single .c file
128 quiet_cmd_host-cobjs = HOSTCC $@
129 cmd_host-cobjs = $(HOSTCC) $(hostc_flags) -c -o $@ $<
130 $(host-cobjs): $(obj)/%.o: $(src)/%.c FORCE
131 $(call if_changed_dep,host-cobjs)
133 # Link an executable based on list of .o files, a mixture of .c and .cc
134 # host-cxxmulti -> executable
135 quiet_cmd_host-cxxmulti = HOSTLD $@
136 cmd_host-cxxmulti = $(HOSTCXX) $(KBUILD_HOSTLDFLAGS) -o $@ \
137 $(foreach o,objs cxxobjs,\
138 $(addprefix $(obj)/, $($(target-stem)-$(o)))) \
139 $(KBUILD_HOSTLDLIBS) $(HOSTLDLIBS_$(target-stem))
140 $(host-cxxmulti): FORCE
141 $(call if_changed,host-cxxmulti)
142 $(call multi_depend, $(host-cxxmulti), , -objs -cxxobjs)
144 # Create .o file from a single .cc (C++) file
145 quiet_cmd_host-cxxobjs = HOSTCXX $@
146 cmd_host-cxxobjs = $(HOSTCXX) $(hostcxx_flags) -c -o $@ $<
147 $(host-cxxobjs): $(obj)/%.o: $(src)/%.cc FORCE
148 $(call if_changed_dep,host-cxxobjs)
150 # Create executable from a single Rust crate (which may consist of
151 # one or more `.rs` files)
152 # host-rust -> Executable
153 quiet_cmd_host-rust = HOSTRUSTC $@
155 $(HOSTRUSTC) $(hostrust_flags) --emit=link=$@ $<
156 $(host-rust): $(obj)/%: $(src)/%.rs FORCE
157 $(call if_changed_dep,host-rust)
159 targets += $(host-csingle) $(host-cmulti) $(host-cobjs) \
160 $(host-cxxmulti) $(host-cxxobjs) $(host-rust)