1# SPDX-License-Identifier: GPL-2.0
2ifneq ($(O),)
3ifeq ($(origin O), command line)
4	dummy := $(if $(shell test -d $(O) || echo $(O)),$(error O=$(O) does not exist),)
5	ABSOLUTE_O := $(shell cd $(O) ; pwd)
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 := $(shell cd $(OUTPUT) && pwd)
17$(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	QUIET_UNINST   = @printf '  UNINST   %s\n' $1;
103  endif
104endif
105