1# SPDX-License-Identifier: GPL-2.0 2ifneq ($(O),) 3ifeq ($(origin O), command line) 4 ABSOLUTE_O := $(realpath $(O)) 5 dummy := $(if $(ABSOLUTE_O),,$(error O=$(O) does not exist)) 6 OUTPUT := $(ABSOLUTE_O)/$(if $(subdir),$(subdir)/) 7 COMMAND_O := O=$(ABSOLUTE_O) 8ifeq ($(objtree),) 9 objtree := $(O) 10endif 11endif 12endif 13 14# check that the output directory actually exists 15ifneq ($(OUTPUT),) 16OUTDIR := $(realpath $(OUTPUT)) 17$(if $(OUTDIR),, $(error output directory "$(OUTPUT)" does not exist)) 18endif 19 20# 21# Include saner warnings here, which can catch bugs: 22# 23EXTRA_WARNINGS := -Wbad-function-cast 24EXTRA_WARNINGS += -Wdeclaration-after-statement 25EXTRA_WARNINGS += -Wformat-security 26EXTRA_WARNINGS += -Wformat-y2k 27EXTRA_WARNINGS += -Winit-self 28EXTRA_WARNINGS += -Wmissing-declarations 29EXTRA_WARNINGS += -Wmissing-prototypes 30EXTRA_WARNINGS += -Wnested-externs 31EXTRA_WARNINGS += -Wno-system-headers 32EXTRA_WARNINGS += -Wold-style-definition 33EXTRA_WARNINGS += -Wpacked 34EXTRA_WARNINGS += -Wredundant-decls 35EXTRA_WARNINGS += -Wshadow 36EXTRA_WARNINGS += -Wstrict-prototypes 37EXTRA_WARNINGS += -Wswitch-default 38EXTRA_WARNINGS += -Wswitch-enum 39EXTRA_WARNINGS += -Wundef 40EXTRA_WARNINGS += -Wwrite-strings 41EXTRA_WARNINGS += -Wformat 42 43CC_NO_CLANG := $(shell $(CC) -dM -E -x c /dev/null | grep -Fq "__clang__"; echo $$?) 44 45ifeq ($(CC_NO_CLANG), 1) 46EXTRA_WARNINGS += -Wstrict-aliasing=3 47endif 48 49# Hack to avoid type-punned warnings on old systems such as RHEL5: 50# We should be changing CFLAGS and checking gcc version, but this 51# will do for now and keep the above -Wstrict-aliasing=3 in place 52# in newer systems. 53# Needed for the __raw_cmpxchg in tools/arch/x86/include/asm/cmpxchg.h 54ifneq ($(filter 3.%,$(MAKE_VERSION)),) # make-3 55EXTRA_WARNINGS += -fno-strict-aliasing 56endif 57 58ifneq ($(findstring $(MAKEFLAGS), w),w) 59PRINT_DIR = --no-print-directory 60else 61NO_SUBDIR = : 62endif 63 64ifneq ($(findstring s,$(filter-out --%,$(MAKEFLAGS))),) 65 silent=1 66endif 67 68# 69# Define a callable command for descending to a new directory 70# 71# Call by doing: $(call descend,directory[,target]) 72# 73descend = \ 74 +mkdir -p $(OUTPUT)$(1) && \ 75 $(MAKE) $(COMMAND_O) subdir=$(if $(subdir),$(subdir)/$(1),$(1)) $(PRINT_DIR) -C $(1) $(2) 76 77QUIET_SUBDIR0 = +$(MAKE) $(COMMAND_O) -C # space to separate -C and subdir 78QUIET_SUBDIR1 = 79 80ifneq ($(silent),1) 81 ifneq ($(V),1) 82 QUIET_CC = @echo ' CC '$@; 83 QUIET_CC_FPIC = @echo ' CC FPIC '$@; 84 QUIET_AR = @echo ' AR '$@; 85 QUIET_LINK = @echo ' LINK '$@; 86 QUIET_MKDIR = @echo ' MKDIR '$@; 87 QUIET_GEN = @echo ' GEN '$@; 88 QUIET_SUBDIR0 = +@subdir= 89 QUIET_SUBDIR1 = ;$(NO_SUBDIR) \ 90 echo ' SUBDIR '$$subdir; \ 91 $(MAKE) $(PRINT_DIR) -C $$subdir 92 QUIET_FLEX = @echo ' FLEX '$@; 93 QUIET_BISON = @echo ' BISON '$@; 94 95 descend = \ 96 +@echo ' DESCEND '$(1); \ 97 mkdir -p $(OUTPUT)$(1) && \ 98 $(MAKE) $(COMMAND_O) subdir=$(if $(subdir),$(subdir)/$(1),$(1)) $(PRINT_DIR) -C $(1) $(2) 99 100 QUIET_CLEAN = @printf ' CLEAN %s\n' $1; 101 QUIET_INSTALL = @printf ' INSTALL %s\n' $1; 102 endif 103endif 104