1ifneq ($(host),$(build)) 2host_toolchain:=$(host)- 3endif 4 5default_host_CC = $(host_toolchain)gcc 6default_host_CXX = $(host_toolchain)g++ 7default_host_AR = $(host_toolchain)ar 8default_host_RANLIB = $(host_toolchain)ranlib 9default_host_STRIP = $(host_toolchain)strip 10default_host_LIBTOOL = $(host_toolchain)libtool 11default_host_INSTALL_NAME_TOOL = $(host_toolchain)install_name_tool 12default_host_OTOOL = $(host_toolchain)otool 13default_host_NM = $(host_toolchain)nm 14 15define add_host_tool_func 16$(host_os)_$1?=$$(default_host_$1) 17$(host_arch)_$(host_os)_$1?=$$($(host_os)_$1) 18$(host_arch)_$(host_os)_$(release_type)_$1?=$$($(host_os)_$1) 19host_$1=$$($(host_arch)_$(host_os)_$1) 20endef 21 22define add_host_flags_func 23$(host_arch)_$(host_os)_$1 += $($(host_os)_$1) 24$(host_arch)_$(host_os)_$(release_type)_$1 += $($(host_os)_$(release_type)_$1) 25host_$1 = $$($(host_arch)_$(host_os)_$1) 26host_$(release_type)_$1 = $$($(host_arch)_$(host_os)_$(release_type)_$1) 27endef 28 29$(foreach tool,CC CXX AR RANLIB STRIP NM LIBTOOL OTOOL INSTALL_NAME_TOOL,$(eval $(call add_host_tool_func,$(tool)))) 30$(foreach flags,CFLAGS CXXFLAGS CPPFLAGS LDFLAGS, $(eval $(call add_host_flags_func,$(flags)))) 31