Makefile.lib

PHONY += __lib
__lib:

#
# Compiler, linker and additional programs
#


ifneq ($(shell $(CC) --version 2>&1 | head -n 1 | grep clang),)
LLVM	:= 1
endif

ifneq ($(LLVM),)
CC		:= clang
LD 		:= ld.lld
STRIP 	:= llvm-strip
OBJCOPY := llvm-objcopy
else
CC		:= i686-pc-linux-gnu-gcc
LD 		:= i686-pc-linux-gnu-gcc
STRIP 	:= i686-pc-linux-gnu-strip
OBJCOPY := i686-pc-linux-gnu-objcopy
endif

#
# Additional programs
#

PY := python3
RM := rm
NM := nm
CP := cp

XR := xorriso -as mkisofs

#
# Flags for compiler and linker
#

DEPFLAGS  = -MMD -MP -MF $@.d

CFLAGS	:= -ffreestanding -Wextra -Os
CFLAGS	+= -Wall -Wstrict-prototypes
CFLAGS	+= -fno-pic

ifneq ($(LLVM),)
CFLAGS	+= -target i386-pc-none-elf
else
CFLAGS	+= -march=i386 -Wl,--gc-sections
endif

LDFLAGS := 

ifneq ($(LLVM),)
LDFLAGS += -m elf_i386 --gc-sections --no-dynamic-linker
else
LDFLAGS += -O2 -nostdlib -lgcc
endif

MODULE_LDFLAGS := $(LDFLAGS)

NMFLAGS	+= -ng

INCLUDE := -Isrc/include -Isrc/arch/$(ELFBOOT_ARCH)/include

#
# Calling Makefiles
#

compile = $(MAKE) -f $(srctree)/Makefile.build obj=$(1) dir=$(2)
cleanup = $(MAKE) -f $(srctree)/Makefile.clean obj=$(1) dir=$(2)

# Building modules

builtin = $(PY) tools/builtin.py -i $(1)
modules = $(MAKE) -f $(srctree)/Makefile.modules obj=$(1) dir=$(2)

# Generating configuration and header files

genconf = $(PY) tools/genconf.py -i $(ELFBOOT).config -o $@

#
# Calling functions
#

squote := '
escsq = $(subst $(squote),'\$(squote)',$1)

cec = $(if $($(quiet)cmd_$(1)), echo '  $(call escsq,$($(quiet)cmd_$(1)))';)
cmd = @$(cec) $(cmd_$(1))

# To reduce the size of the resulting binary, we remove unused sections
# like the .eh_frame which only adds unwinding information which we are
# not using anyway.

unused_sections += .comment
unused_sections += .debug_*
unused_sections += .eh_frame

OBJCOPY_SECTION := $(foreach section,$(unused_sections),-R $(section))

#
# Utility functions and Tools
#

ELFCONF	:= $(srctree)/tools/elfconf

quiet_cmd_ec_elf = ELFCONF $(2).elf
      cmd_ec_elf = $(ELFCONF) -f $(2).elf -s $(3) -v $(shell stat -L -c %s $(4))

quiet_cmd_st_elf = STRIP   $(2).elf
      cmd_st_elf = $(STRIP) -S $(2).elf

quiet_cmd_oc_bin = OBJCOPY $(2).bin
      cmd_oc_bin = $(OBJCOPY) -O binary $(2).elf $(2).bin

elfconf = $(call cmd,ec_elf,$(1),$(2),$(3))
gcstrip = $(call cmd,st_elf,$(1))
objcopy = $(call cmd,oc_bin,$(1))
mod_map = $(call cmd,ko_map)

#
# Collecting object files for compilation
#

define collect_target
objtree := $$(objtree)/$(1)
srctree := $$(srctree)/$(1)

$(2)-y  :=
$(2)-m  :=
$(2)-d  :=

include $$(srctree)/Makefile

$(2)-ccfl	+= $$($(2)-cflags)
$(2)-ccfl	:= $$(sort $$($(2)-ccfl))
$(2)-objs	+= $$(patsubst %,$$(objtree)/%,$$($(2)-y))
$(2)-mods	+= $$(patsubst %,$$(objtree)/%,$$($(2)-m))

$$(foreach subdir,$$($(2)-d),$$(eval $$(call collect_target,$$(subdir),$(2))))

srctree := $$(patsubst %/$(1),%,$$(srctree))
objtree := $$(patsubst %/$(1),%,$$(objtree))
endef