ifneq ($(O),) ifeq ($(origin O), command line) dummy := $(if $(shell test -d $(O) || echo $(O)),$(error O=$(O) does not exist),) ABSOLUTE_O := $(shell cd $(O) ; pwd) OUTPUT := $(ABSOLUTE_O)/$(if $(subdir),$(subdir)/) COMMAND_O := O=$(ABSOLUTE_O) ifeq ($(objtree),) objtree := $(O) endif endif endif # check that the output directory actually exists ifneq ($(OUTPUT),) OUTDIR := $(shell cd $(OUTPUT) && /bin/pwd) $(if $(OUTDIR),, $(error output directory "$(OUTPUT)" does not exist)) endif # # Include saner warnings here, which can catch bugs: # EXTRA_WARNINGS := -Wbad-function-cast EXTRA_WARNINGS += -Wdeclaration-after-statement EXTRA_WARNINGS += -Wformat-security EXTRA_WARNINGS += -Wformat-y2k EXTRA_WARNINGS += -Winit-self EXTRA_WARNINGS += -Wmissing-declarations EXTRA_WARNINGS += -Wmissing-prototypes EXTRA_WARNINGS += -Wnested-externs EXTRA_WARNINGS += -Wno-system-headers EXTRA_WARNINGS += -Wold-style-definition EXTRA_WARNINGS += -Wpacked EXTRA_WARNINGS += -Wredundant-decls EXTRA_WARNINGS += -Wshadow EXTRA_WARNINGS += -Wstrict-prototypes EXTRA_WARNINGS += -Wswitch-default EXTRA_WARNINGS += -Wswitch-enum EXTRA_WARNINGS += -Wundef EXTRA_WARNINGS += -Wwrite-strings EXTRA_WARNINGS += -Wformat CC_NO_CLANG := $(shell $(CC) -dM -E -x c /dev/null | grep -Fq "__clang__"; echo $$?) ifeq ($(CC_NO_CLANG), 1) EXTRA_WARNINGS += -Wstrict-aliasing=3 endif # Hack to avoid type-punned warnings on old systems such as RHEL5: # We should be changing CFLAGS and checking gcc version, but this # will do for now and keep the above -Wstrict-aliasing=3 in place # in newer systems. # Needed for the __raw_cmpxchg in tools/arch/x86/include/asm/cmpxchg.h ifneq ($(filter 3.%,$(MAKE_VERSION)),) # make-3 EXTRA_WARNINGS += -fno-strict-aliasing endif ifneq ($(findstring $(MAKEFLAGS), w),w) PRINT_DIR = --no-print-directory else NO_SUBDIR = : endif ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),) silent=1 endif # # Define a callable command for descending to a new directory # # Call by doing: $(call descend,directory[,target]) # descend = \ +mkdir -p $(OUTPUT)$(1) && \ $(MAKE) $(COMMAND_O) subdir=$(if $(subdir),$(subdir)/$(1),$(1)) $(PRINT_DIR) -C $(1) $(2) QUIET_SUBDIR0 = +$(MAKE) $(COMMAND_O) -C # space to separate -C and subdir QUIET_SUBDIR1 = ifneq ($(silent),1) ifneq ($(V),1) QUIET_CC = @echo ' CC '$@; QUIET_CC_FPIC = @echo ' CC FPIC '$@; QUIET_AR = @echo ' AR '$@; QUIET_LINK = @echo ' LINK '$@; QUIET_MKDIR = @echo ' MKDIR '$@; QUIET_GEN = @echo ' GEN '$@; QUIET_SUBDIR0 = +@subdir= QUIET_SUBDIR1 = ;$(NO_SUBDIR) \ echo ' SUBDIR '$$subdir; \ $(MAKE) $(PRINT_DIR) -C $$subdir QUIET_FLEX = @echo ' FLEX '$@; QUIET_BISON = @echo ' BISON '$@; descend = \ +@echo ' DESCEND '$(1); \ mkdir -p $(OUTPUT)$(1) && \ $(MAKE) $(COMMAND_O) subdir=$(if $(subdir),$(subdir)/$(1),$(1)) $(PRINT_DIR) -C $(1) $(2) QUIET_CLEAN = @printf ' CLEAN %s\n' $1; QUIET_INSTALL = @printf ' INSTALL %s\n' $1; endif endif