| # SPDX-License-Identifier: GPL-2.0 |
| ifneq ($(O),) |
| ifeq ($(origin O), command line) |
| dummy := $(if $(shell cd $(PWD); test -d $(O) || echo $(O)),$(error O=$(O) does not exist),) |
| ABSOLUTE_O := $(shell cd $(PWD); 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) && 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 += -Wstrict-prototypes |
| EXTRA_WARNINGS += -Wswitch-default |
| EXTRA_WARNINGS += -Wswitch-enum |
| EXTRA_WARNINGS += -Wundef |
| EXTRA_WARNINGS += -Wwrite-strings |
| EXTRA_WARNINGS += -Wformat |
| EXTRA_WARNINGS += -Wno-type-limits |
| |
| # Makefiles suck: This macro sets a default value of $(2) for the |
| # variable named by $(1), unless the variable has been set by |
| # environment or command line. This is necessary for CC and AR |
| # because make sets default values, so the simpler ?= approach |
| # won't work as expected. |
| define allow-override |
| $(if $(or $(findstring environment,$(origin $(1))),\ |
| $(findstring command line,$(origin $(1)))),,\ |
| $(eval $(1) = $(2))) |
| endef |
| |
| ifneq ($(LLVM),) |
| $(call allow-override,CC,clang) |
| $(call allow-override,AR,llvm-ar) |
| $(call allow-override,LD,ld.lld) |
| $(call allow-override,CXX,clang++) |
| $(call allow-override,STRIP,llvm-strip) |
| else |
| # Allow setting various cross-compile vars or setting CROSS_COMPILE as a prefix. |
| $(call allow-override,CC,$(CROSS_COMPILE)gcc) |
| $(call allow-override,AR,$(CROSS_COMPILE)ar) |
| $(call allow-override,LD,$(CROSS_COMPILE)ld) |
| $(call allow-override,CXX,$(CROSS_COMPILE)g++) |
| $(call allow-override,STRIP,$(CROSS_COMPILE)strip) |
| endif |
| |
| CC_NO_CLANG := $(shell $(CC) -dM -E -x c /dev/null | grep -Fq "__clang__"; echo $$?) |
| |
| ifneq ($(LLVM),) |
| HOSTAR ?= llvm-ar |
| HOSTCC ?= clang |
| HOSTLD ?= ld.lld |
| else |
| HOSTAR ?= ar |
| HOSTCC ?= gcc |
| HOSTLD ?= ld |
| endif |
| |
| # Some tools require Clang, LLC and/or LLVM utils |
| CLANG ?= clang |
| LLC ?= llc |
| LLVM_CONFIG ?= llvm-config |
| LLVM_OBJCOPY ?= llvm-objcopy |
| LLVM_STRIP ?= llvm-strip |
| |
| 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 |
| # |
| # See https://lore.kernel.org/lkml/9a8748490611281710g78402fbeh8ff7fcc162dbcbca@mail.gmail.com/ |
| # and https://gcc.gnu.org/gcc-4.8/changes.html, |
| # that takes into account Linus's comments (search for Wshadow) for the reasoning about |
| # -Wshadow not being interesting before gcc 4.8. |
| |
| ifneq ($(filter 3.%,$(MAKE_VERSION)),) # make-3 |
| EXTRA_WARNINGS += -fno-strict-aliasing |
| EXTRA_WARNINGS += -Wno-shadow |
| else |
| EXTRA_WARNINGS += -Wshadow |
| 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_CLANG = @echo ' CLANG '$@; |
| 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 '$@; |
| QUIET_BISON = @echo ' BISON '$@; |
| QUIET_GENSKEL = @echo ' GENSKEL '$@; |
| |
| descend = \ |
| +@echo ' DESCEND '$(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; |
| QUIET_UNINST = @printf ' UNINST %s\n' $1; |
| endif |
| endif |
| |
| pound := \# |