summaryrefslogtreecommitdiffstats
path: root/common.mk
blob: b8aade55642a82cb9653317f22e603671e45e1df (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
# Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
#
# If this file is part of another source distribution, it's license may be
# stored in LICENSE.makefile or LICENSE.common.mk.
#
# NOTE NOTE NOTE
#  The authoritative common.mk is located in:
#    https://chromium.googlesource.com/chromiumos/platform/common-mk.git
#  Please make all changes there, then copy into place in other repos.
# NOTE NOTE NOTE
#
# This file provides a common architecture for building C/C++ source trees.
# It uses recursive makefile inclusion to create a single make process which
# can be built in the source tree or with the build artifacts placed elsewhere.
#
# It is fully parallelizable for all targets, including static archives.
#
# To use:
# 1. Place common.mk in your top source level
# 2. In your top-level Makefile, place "include common.mk" at the top
# 3. In all subdirectories, create a 'module.mk' file that starts with:
#      include common.mk
#    And then contains the remainder of your targets.
# 4. All build targets should look like:
#    relative/path/target: relative/path/obj.o
#
# See existing makefiles for rule examples.
#
# Exported macros:
#   - cc_binary, cxx_binary provide standard compilation steps for binaries
#   - cxx_library, cc_library provide standard compilation steps for
#     shared objects.
#   All of the above optionally take an argument for extra flags.
#   - update_archive creates/updates a given .a target
#
# Instead of using the build macros, most users can just use wrapped targets:
#   - CXX_BINARY, CC_BINARY, CC_STATIC_BINARY, CXX_STATIC_BINARY
#   - CXX_LIBRARY, CC_LIBRARY, CC_STATIC_LIBRARY, CXX_STATIC_LIBRARY
#   - E.g., CXX_BINARY(mahbinary): foo.o
#   - object.depends targets may be used when a prerequisite is required for an
#     object file. Because object files result in multiple build artifacts to
#     handle PIC and PIE weirdness. E.g.
#       foo.o.depends: generated/dbus.h
#   - TEST(binary) or TEST(CXX_BINARY(binary)) may be used as a prerequisite
#     for the tests target to trigger an automated test run.
#   - CLEAN(file_or_dir) dependency can be added to 'clean'.
#
# If source code is being generated, rules will need to be registered for
# compiling the objects.  This can be done by adding one of the following
# to the Makefile:
#   - For C source files
#     $(eval $(call add_object_rules,sub/dir/gen_a.o sub/dir/gen_b.o,CC,c))
#   - For C++ source files
#     $(eval $(call add_object_rules,sub/dir/gen_a.o sub/dir/gen_b.o,CXX,cc))
#
# Exported targets meant to have prerequisites added to:
#  - all - Your desired targets should be given
#  - tests - Any TEST(test_binary) targets should be given
#  - FORCE - force the given target to run regardless of changes
#            In most cases, using .PHONY is preferred.
#
# Possible command line variables:
#   - COLOR=[0|1] to set ANSI color output (default: 1)
#   - VERBOSE=[0|1] to hide/show commands (default: 0)
#   - MODE=[opt|dbg|profiling] (default: opt)
#          opt - Enable optimizations for release builds
#          dbg - Turn down optimization for debugging
#          profiling - Turn off optimization and turn on profiling/coverage
#                      support.
#   - ARCH=[x86|arm|supported qemu name] (default: from portage or uname -m)
#   - SPLITDEBUG=[0|1] splits debug info in target.debug (default: 0)
#        If NOSTRIP=1, SPLITDEBUG will never strip the final emitted objects.
#   - NOSTRIP=[0|1] determines if binaries are stripped. (default: 1)
#        NOSTRIP=0 and MODE=opt will also drop -g from the CFLAGS.
#   - VALGRIND=[0|1] runs tests under valgrind (default: 0)
#   - OUT=/path/to/builddir puts all output in given path (default: $PWD)
#   - VALGRIND_ARGS="" supplies extra memcheck arguments
#
# Per-target(-ish) variable:
#   - NEEDS_ROOT=[0|1] allows a TEST() target to run with root.
#     Default is 0 unless it is running under QEmu.
#   - NEEDS_MOUNTS=[0|1] allows a TEST() target running on QEmu to get
#     setup mounts in the $(SYSROOT)
#
# Caveats:
# - Directories or files with spaces in them DO NOT get along with GNU Make.
#   If you need them, all uses of dir/notdir/etc will need to have magic
#   wrappers.  Proceed at risk to your own sanity.
# - External CXXFLAGS and CFLAGS should be passed via the environment since
#   this file does not use 'override' to control them.
# - Our version of GNU Make doesn't seem to support the 'private' variable
#   annotation, so you can't tag a variable private on a wrapping target.

# Behavior configuration variables
SPLITDEBUG ?= 0
NOSTRIP ?= 1
VALGRIND ?= 0
COLOR ?= 1
VERBOSE ?= 0
MODE ?= opt
ARCH ?= $(shell uname -m)
NEEDS_ROOT = 0
NEEDS_MOUNTS = 0

# Put objects in a separate tree based on makefile locations
# This means you can build a tree without touching it:
#   make -C $SRCDIR  # will create ./build-$(MODE)
# Or
#   make -C $SRCDIR OUT=$PWD
# This variable is extended on subdir calls and doesn't need to be re-called.
OUT ?= $(PWD)/

# Make OUT now so we can use realpath.
$(shell mkdir -p "$(OUT)")

# TODO(wad) Relative paths are resolved against SRC and not the calling dir.
# Ensure a command-line supplied OUT has a slash
override OUT := $(realpath $(OUT))/

# SRC is not meant to be set by the end user, but during make call relocation.
# $(PWD) != $(CURDIR) all the time.
export SRC ?= $(CURDIR)

# Re-start in the $(OUT) directory if we're not there.
# We may be invoked using -C or bare and we need to ensure behavior
# is consistent so we check both PWD vs OUT and PWD vs CURDIR.
override RELOCATE_BUILD := 0
ifneq (${PWD}/,${OUT})
override RELOCATE_BUILD := 1
endif
# Make sure we're running with no builtin targets. They cause
# leakage and mayhem!
ifneq (${PWD},${CURDIR})
override RELOCATE_BUILD := 1
# If we're run from the build dir, don't let it get cleaned up later.
ifeq (${PWD}/,${OUT})
$(shell touch "$(PWD)/.dont_delete_on_clean")
endif
endif  # ifneq (${PWD},${CURDIR}

# "Relocate" if we need to restart without implicit rules.
ifeq ($(subst r,,$(MAKEFLAGS)),$(MAKEFLAGS))
override RELOCATE_BUILD := 1
endif

ifeq (${RELOCATE_BUILD},1)
# By default, silence build output. Reused below as well.
QUIET = @
ifeq ($(VERBOSE),1)
  QUIET=
endif

# This target will override all targets, including prerequisites. To avoid
# calling $(MAKE) once per prereq on the given CMDGOAL, we guard it with a local
# variable.
RUN_ONCE := 0
MAKECMDGOALS ?= all
# Keep the rules split as newer make does not allow them to be declared
# on the same line.  But the way :: rules work, the _all here will also
# invoke the %:: rule while retaining "_all" as the default.
_all::
%::
	$(if $(filter 0,$(RUN_ONCE)), \
	  cd "$(OUT)" && \
	  $(MAKE) -r -I "$(SRC)" -f "$(CURDIR)/Makefile" \
	    SRC="$(CURDIR)" OUT="$(OUT)" $(foreach g,$(MAKECMDGOALS),"$(g)"),)
	$(eval RUN_ONCE := 1)
pass-to-subcall := 1
endif

ifeq ($(pass-to-subcall),)

# Only call MODULE if we're in a submodule
MODULES_LIST := $(filter-out Makefile %.d,$(MAKEFILE_LIST))
ifeq ($(words $(filter-out Makefile common.mk %.d $(SRC)/Makefile \
                           $(SRC)/common.mk,$(MAKEFILE_LIST))),0)

# All the top-level defines outside of module.mk.

#
# Helper macros
#

# Create the directory if it doesn't yet exist.
define auto_mkdir
  $(if $(wildcard $(dir $1)),$2,$(QUIET)mkdir -p "$(dir $1)")
endef

# Creates the actual archive with an index.
# The target $@ must end with .pic.a or .pie.a.
define update_archive
  $(call auto_mkdir,$(TARGET_OR_MEMBER))
  $(QUIET)# Create the archive in one step to avoid parallel use accessing it
  $(QUIET)# before all the symbols are present.
  @$(ECHO) "AR		$(subst \
$(SRC)/,,$(^:.o=$(suffix $(basename $(TARGET_OR_MEMBER))).o)) \
-> $(subst $(SRC)/,,$(TARGET_OR_MEMBER))"
  $(QUIET)$(AR) rcs $(TARGET_OR_MEMBER) \
          $(subst $(SRC)/,,$(^:.o=$(suffix $(basename $(TARGET_OR_MEMBER))).o))
endef

# Default compile from objects using pre-requisites but filters out
# subdirs and .d files.
define cc_binary
  $(call COMPILE_BINARY_implementation,CC,$(CFLAGS) $(1),$(EXTRA_FLAGS))
endef

define cxx_binary
  $(call COMPILE_BINARY_implementation,CXX,$(CXXFLAGS) $(1),$(EXTRA_FLAGS))
endef

# Default compile from objects using pre-requisites but filters out
# subdirs and .d files.
define cc_library
  $(call COMPILE_LIBRARY_implementation,CC,$(CFLAGS) $(1),$(EXTRA_FLAGS))
endef
define cxx_library
  $(call COMPILE_LIBRARY_implementation,CXX,$(CXXFLAGS) $(1),$(EXTRA_FLAGS))
endef

# Deletes files silently if they exist. Meant for use in any local
# clean targets.
define silent_rm
  $(if $(wildcard $(1)),
  $(QUIET)($(ECHO) -n '$(COLOR_RED)CLEANFILE$(COLOR_RESET)		' && \
    $(ECHO) '$(subst $(OUT)/,,$(wildcard $(1)))' && \
    $(RM) $(1) 2>/dev/null) || true,)
endef
define silent_rmdir
  $(if $(wildcard $(1)),
    $(if $(wildcard $(1)/*),
  $(QUIET)# $(1) not empty [$(wildcard $(1)/*)]. Not deleting.,
  $(QUIET)($(ECHO) -n '$(COLOR_RED)CLEANDIR$(COLOR_RESET)		' && \
    $(ECHO) '$(subst $(OUT)/,,$(wildcard $(1)))' && \
    $(RMDIR) $(1) 2>/dev/null) || true),)
endef

#
# Default variable values
#

# Only override toolchain vars if they are from make.
CROSS_COMPILE ?=
define override_var
ifneq ($(filter undefined default,$(origin $1)),)
$1 = $(CROSS_COMPILE)$2
endif
endef
$(eval $(call override_var,AR,ar))
$(eval $(call override_var,CC,gcc))
$(eval $(call override_var,CXX,g++))
$(eval $(call override_var,OBJCOPY,objcopy))
$(eval $(call override_var,PKG_CONFIG,pkg-config))
$(eval $(call override_var,RANLIB,ranlib))
$(eval $(call override_var,STRIP,strip))

RMDIR ?= rmdir
ECHO = /bin/echo -e

ifeq ($(lastword $(subst /, ,$(CC))),clang)
CDRIVER = clang
else
CDRIVER = gcc
endif

ifeq ($(lastword $(subst /, ,$(CXX))),clang++)
CXXDRIVER = clang
else
CXXDRIVER = gcc
endif

# To update these from an including Makefile:
#  CXXFLAGS += -mahflag  # Append to the list
#  CXXFLAGS := -mahflag $(CXXFLAGS) # Prepend to the list
#  CXXFLAGS := $(filter-out badflag,$(CXXFLAGS)) # Filter out a value
# The same goes for CFLAGS.
COMMON_CFLAGS-gcc := -fstack-protector-strong -fvisibility=internal -ggdb3 \
  -Wa,--noexecstack
COMMON_CFLAGS-clang := -fstack-protector-all -fvisibility=hidden -ggdb
COMMON_CFLAGS := -Wall -Werror -fno-strict-aliasing -O1 -Wformat=2
CXXFLAGS += $(COMMON_CFLAGS) $(COMMON_CFLAGS-$(CXXDRIVER))
CFLAGS += $(COMMON_CFLAGS) $(COMMON_CFLAGS-$(CDRIVER))
CPPFLAGS += -D_FORTIFY_SOURCE=2


ifeq ($(MODE),opt)
  # Up the optimizations.
  CFLAGS := $(filter-out -O1,$(CFLAGS)) -O2
  CXXFLAGS := $(filter-out -O1,$(CXXFLAGS)) -O2
  # Only drop -g* if symbols aren't desired.
  ifeq ($(NOSTRIP),0)
    # TODO: do we want -fomit-frame-pointer on x86?
    CFLAGS := $(filter-out -ggdb3,$(CFLAGS))
    CXXFLAGS := $(filter-out -ggdb3,$(CXXFLAGS))
  endif
endif

ifeq ($(MODE),profiling)
  CFLAGS := $(CFLAGS) -O0 -g  --coverage
  CXXFLAGS := $(CXXFLAGS) -O0 -g  --coverage
  LDFLAGS := $(LDFLAGS) --coverage
endif

LDFLAGS := $(LDFLAGS) -Wl,-z,relro -Wl,-z,noexecstack -Wl,-z,now

# Fancy helpers for color if a prompt is defined
ifeq ($(COLOR),1)
COLOR_RESET = \x1b[0m
COLOR_GREEN = \x1b[32;01m
COLOR_RED = \x1b[31;01m
COLOR_YELLOW = \x1b[33;01m
endif

# By default, silence build output.
QUIET = @
ifeq ($(VERBOSE),1)
  QUIET=
endif

#
# Implementation macros for compile helpers above
#

# Useful for dealing with pie-broken toolchains.
# Call make with PIE=0 to disable default PIE use.
OBJ_PIE_FLAG = -fPIE
COMPILE_PIE_FLAG = -pie
ifeq ($(PIE),0)
  OBJ_PIE_FLAG =
  COMPILE_PIE_FLAG =
endif

# Favor member targets first for CXX_BINARY(%) magic.
# And strip out nested members if possible.
LP := (
RP := )
TARGET_OR_MEMBER = $(lastword $(subst $(LP), ,$(subst $(RP),,$(or $%,$@))))

# Default compile from objects using pre-requisites but filters out
# all non-.o files.
define COMPILE_BINARY_implementation
  @$(ECHO) "LD$(1)		$(subst $(PWD)/,,$(TARGET_OR_MEMBER))"
  $(call auto_mkdir,$(TARGET_OR_MEMBER))
  $(QUIET)$($(1)) $(COMPILE_PIE_FLAGS) -o $(TARGET_OR_MEMBER) \
    $(2) $(LDFLAGS) \
    $(filter %.o %.a,$(^:.o=.pie.o)) \
    $(foreach so,$(filter %.so,$^),-L$(dir $(so)) \
                            -l$(patsubst lib%,%,$(basename $(notdir $(so))))) \
    $(LDLIBS)
  $(call conditional_strip)
  @$(ECHO) -n "BIN		"
  @$(ECHO) "$(COLOR_GREEN)$(subst $(PWD)/,,$(TARGET_OR_MEMBER))$(COLOR_RESET)"
  @$(ECHO) "	$(COLOR_YELLOW)-----$(COLOR_RESET)"
endef

# TODO: add version support extracted from PV environment variable
#ifeq ($(PV),9999)
#$(warning PV=$(PV). If shared object versions matter, please force PV=.)
#endif
# Then add -Wl,-soname,$@.$(PV) ?

# Default compile from objects using pre-requisites but filters out
# all non-.o values. (Remember to add -L$(OUT) -llib)
COMMA := ,
define COMPILE_LIBRARY_implementation
  @$(ECHO) "SHARED$(1)	$(subst $(PWD)/,,$(TARGET_OR_MEMBER))"
  $(call auto_mkdir,$(TARGET_OR_MEMBER))
  $(QUIET)$($(1)) -shared -Wl,-E -o $(TARGET_OR_MEMBER) \
    $(2) $(LDFLAGS) \
    $(if $(filter %.a,$^),-Wl$(COMMA)--whole-archive,) \
    $(filter %.o ,$(^:.o=.pic.o)) \
    $(foreach a,$(filter %.a,$^),-L$(dir $(a)) \
                            -l$(patsubst lib%,%,$(basename $(notdir $(a))))) \
    $(foreach so,$(filter %.so,$^),-L$(dir $(so)) \
                            -l$(patsubst lib%,%,$(basename $(notdir $(so))))) \
    $(LDLIBS)
  $(call conditional_strip)
  @$(ECHO) -n "LIB		$(COLOR_GREEN)"
  @$(ECHO) "$(subst $(PWD)/,,$(TARGET_OR_MEMBER))$(COLOR_RESET)"
  @$(ECHO) "	$(COLOR_YELLOW)-----$(COLOR_RESET)"
endef

define conditional_strip
  $(if $(filter 0,$(NOSTRIP)),$(call strip_artifact))
endef

define strip_artifact
  @$(ECHO) "STRIP		$(subst $(OUT)/,,$(TARGET_OR_MEMBER))"
  $(if $(filter 1,$(SPLITDEBUG)), @$(ECHO) -n "DEBUG	"; \
    $(ECHO) "$(COLOR_YELLOW)\
$(subst $(OUT)/,,$(TARGET_OR_MEMBER)).debug$(COLOR_RESET)")
  $(if $(filter 1,$(SPLITDEBUG)), \
    $(QUIET)$(OBJCOPY) --only-keep-debug "$(TARGET_OR_MEMBER)" \
      "$(TARGET_OR_MEMBER).debug")
  $(if $(filter-out dbg,$(MODE)),$(QUIET)$(STRIP) --strip-unneeded \
    "$(TARGET_OR_MEMBER)",)
endef

#
# Global pattern rules
#

# Below, the archive member syntax is abused to create fancier
# syntactic sugar for recipe authors that avoids needed to know
# subcall options.  The downside is that make attempts to look
# into the phony archives for timestamps. This will cause the final
# target to be rebuilt/linked on _every_ call to make even when nothing
# has changed.  Until a better way presents itself, we have helpers that
# do the stat check on make's behalf.  Dodgy but simple.
define old_or_no_timestamp
  $(if $(realpath $%),,$(1))
  $(if $(shell find $^ -cnewer "$%" 2>/dev/null),$(1))
endef

define check_deps
  $(if $(filter 0,$(words $^)),\
    $(error Missing dependencies or declaration of $@($%)),)
endef

# Build a cxx target magically
CXX_BINARY(%):
	$(call check_deps)
	$(call old_or_no_timestamp,$(call cxx_binary))
clean: CLEAN(CXX_BINARY*)

CC_BINARY(%):
	$(call check_deps)
	$(call old_or_no_timestamp,$(call cc_binary))
clean: CLEAN(CC_BINARY*)

CXX_STATIC_BINARY(%):
	$(call check_deps)
	$(call old_or_no_timestamp,$(call cxx_binary,-static))
clean: CLEAN(CXX_STATIC_BINARY*)

CC_STATIC_BINARY(%):
	$(call check_deps)
	$(call old_or_no_timestamp,$(call cc_binary,-static))
clean: CLEAN(CC_STATIC_BINARY*)

CXX_LIBRARY(%):
	$(call check_deps)
	$(call old_or_no_timestamp,$(call cxx_library))
clean: CLEAN(CXX_LIBRARY*)

CXX_LIBARY(%):
	$(error Typo alert! LIBARY != LIBRARY)

CC_LIBRARY(%):
	$(call check_deps)
	$(call old_or_no_timestamp,$(call cc_library))
clean: CLEAN(CC_LIBRARY*)

CC_LIBARY(%):
	$(error Typo alert! LIBARY != LIBRARY)

CXX_STATIC_LIBRARY(%):
	$(call check_deps)
	$(call old_or_no_timestamp,$(call update_archive))
clean: CLEAN(CXX_STATIC_LIBRARY*)

CXX_STATIC_LIBARY(%):
	$(error Typo alert! LIBARY != LIBRARY)

CC_STATIC_LIBRARY(%):
	$(call check_deps)
	$(call old_or_no_timestamp,$(call update_archive))
clean: CLEAN(CC_STATIC_LIBRARY*)

CC_STATIC_LIBARY(%):
	$(error Typo alert! LIBARY != LIBRARY)


TEST(%): % qemu_chroot_install
	$(call TEST_implementation)
.PHONY: TEST

# multiple targets with a wildcard need to share an directory.
# Don't use this directly it just makes sure the directory is removed _after_
# the files are.
CLEANFILE(%):
	$(call silent_rm,$(TARGET_OR_MEMBER))
.PHONY: CLEANFILE

CLEAN(%): CLEANFILE(%)
	$(QUIET)# CLEAN($%) meta-target called
	$(if $(filter-out $(PWD)/,$(dir $(abspath $(TARGET_OR_MEMBER)))), \
	  $(call silent_rmdir,$(dir $(abspath $(TARGET_OR_MEMBER)))),\
	  $(QUIET)# Not deleting $(dir $(abspath $(TARGET_OR_MEMBER))) yet.)
.PHONY: CLEAN

#
# Top-level objects and pattern rules
#

# All objects for .c files at the top level
C_OBJECTS = $(patsubst $(SRC)/%.c,%.o,$(wildcard $(SRC)/*.c))


# All objects for .cxx files at the top level
CXX_OBJECTS = $(patsubst $(SRC)/%.cc,%.o,$(wildcard $(SRC)/*.cc))

# Note, the catch-all pattern rules don't work in subdirectories because
# we're building from the $(OUT) directory. At the top-level (here) they will
# work, but we go ahead and match using the module form.  Then we can place a
# generic pattern rule to capture leakage from the main Makefile. (Later in the
# file.)
#
# The reason target specific pattern rules work well for modules,
# MODULE_C_OBJECTS, is because it scopes the behavior to the given target which
# ensures we get a relative directory offset from $(OUT) which otherwise would
# not match without further magic on a per-subdirectory basis.

# Creates object file rules. Call with eval.
# $(1) list of .o files
# $(2) source type (CC or CXX)
# $(3) source suffix (cc or c)
# $(4) compiler flag name (CFLAGS or CXXFLAGS)
# $(5) source dir: _only_ if $(SRC). Leave blank for obj tree.
define add_object_rules
$(patsubst %.o,%.pie.o,$(1)): %.pie.o: $(5)%.$(3) %.o.depends
	$$(call auto_mkdir,$$@)
	$$(call OBJECT_PATTERN_implementation,$(2),\
          $$(basename $$@),$$($(4)) $$(CPPFLAGS) $$(OBJ_PIE_FLAG))

$(patsubst %.o,%.pic.o,$(1)): %.pic.o: $(5)%.$(3) %.o.depends
	$$(call auto_mkdir,$$@)
	$$(call OBJECT_PATTERN_implementation,$(2),\
          $$(basename $$@),$$($(4)) $$(CPPFLAGS) -fPIC)

# Placeholder for depends
$(patsubst %.o,%.o.depends,$(1)):
	$$(call auto_mkdir,$$@)
	$$(QUIET)touch "$$@"

$(1): %.o: %.pic.o %.pie.o
	$$(call auto_mkdir,$$@)
	$$(QUIET)touch "$$@"
endef

define OBJECT_PATTERN_implementation
  @$(ECHO) "$(1)		$(subst $(SRC)/,,$<) -> $(2).o"
  $(call auto_mkdir,$@)
  $(QUIET)$($(1)) -c -MD -MF $(2).d $(3) -o $(2).o $<
  $(QUIET)# Wrap all the deps in $$(wildcard) so a missing header
  $(QUIET)# won't cause weirdness.  First we remove newlines and \,
  $(QUIET)# then wrap it.
  $(QUIET)sed -i -e :j -e '$$!N;s|\\\s*\n| |;tj' \
    -e 's|^\(.*\s*:\s*\)\(.*\)$$|\1 $$\(wildcard \2\)|' $(2).d
endef

# Now actually register handlers for C(XX)_OBJECTS.
$(eval $(call add_object_rules,$(C_OBJECTS),CC,c,CFLAGS,$(SRC)/))
$(eval $(call add_object_rules,$(CXX_OBJECTS),CXX,cc,CXXFLAGS,$(SRC)/))

# Disable default pattern rules to help avoid leakage.
# These may already be handled by '-r', but let's keep it to be safe.
%: %.o ;
%.a: %.o ;
%.o: %.c ;
%.o: %.cc ;

# NOTE: A specific rule for archive objects is avoided because parallel
#       update of the archive causes build flakiness.
# Instead, just make the objects the prerequisites and use update_archive
# To use the foo.a(obj.o) functionality, targets would need to specify the
# explicit object they expect on the prerequisite line.

#
# Architecture detection and QEMU wrapping
#

HOST_ARCH ?= $(shell uname -m)
override ARCH := $(strip $(ARCH))
override HOST_ARCH := $(strip $(HOST_ARCH))
# emake will supply "x86" or "arm" for ARCH, but
# if uname -m runs and you get x86_64, then this subst
# will break.
ifeq ($(subst x86,i386,$(ARCH)),i386)
  QEMU_ARCH := $(subst x86,i386,$(ARCH))  # x86 -> i386
else ifeq ($(subst amd64,x86_64,$(ARCH)),x86_64)
  QEMU_ARCH := $(subst amd64,x86_64,$(ARCH))  # amd64 -> x86_64
else
  QEMU_ARCH = $(ARCH)
endif
override QEMU_ARCH := $(strip $(QEMU_ARCH))

# If we're cross-compiling, try to use qemu for running the tests.
ifneq ($(QEMU_ARCH),$(HOST_ARCH))
  ifeq ($(SYSROOT),)
    $(info SYSROOT not defined. qemu-based testing disabled)
  else
    # A SYSROOT is assumed for QEmu use.
    USE_QEMU ?= 1

    # Allow 64-bit hosts to run 32-bit without qemu.
    ifeq ($(HOST_ARCH),x86_64)
      ifeq ($(QEMU_ARCH),i386)
        USE_QEMU = 0
      endif
    endif
  endif
else
  USE_QEMU ?= 0
endif

SYSROOT_OUT = $(OUT)
ifneq ($(SYSROOT),)
  SYSROOT_OUT = $(subst $(SYSROOT),,$(OUT))
else
  # Default to / when all the empty-sysroot logic is done.
  SYSROOT = /
endif


#
# Output full configuration at top level
#

# Don't show on clean
ifneq ($(MAKECMDGOALS),clean)
  $(info build configuration:)
  $(info - OUT=$(OUT))
  $(info - SRC=$(SRC))
  $(info - MODE=$(MODE))
  $(info - SPLITDEBUG=$(SPLITDEBUG))
  $(info - NOSTRIP=$(NOSTRIP))
  $(info - VALGRIND=$(VALGRIND))
  $(info - COLOR=$(COLOR))
  $(info - ARCH=$(ARCH))
  $(info - QEMU_ARCH=$(QEMU_ARCH))
  $(info - SYSROOT=$(SYSROOT))
  $(info )
endif

#
# Standard targets with detection for when they are improperly configured.
#

# all does not include tests by default
all:
	$(QUIET)(test -z "$^" && \
	$(ECHO) "You must add your targets as 'all' prerequisites") || true
	$(QUIET)test -n "$^"

# Builds and runs tests for the target arch
# Run them in parallel
# After the test have completed, if profiling, run coverage analysis
tests:
ifeq ($(MODE),profiling)
	@$(ECHO) "COVERAGE [$(COLOR_YELLOW)STARTED$(COLOR_RESET)]"
	$(QUIET)FILES="";						\
		for GCNO in `find . -name "*.gcno"`; do			\
			GCDA="$${GCNO%.gcno}.gcda";			\
			if [ -e $${GCDA} ]; then			\
				FILES="$${FILES} $${GCDA}";		\
			fi						\
		done;							\
		if [ -n "$${FILES}" ]; then				\
			gcov -l $${FILES};				\
			lcov --capture --directory .			\
				--output-file=lcov-coverage.info;	\
			genhtml lcov-coverage.info			\
				--output-directory lcov-html;		\
		fi
	@$(ECHO) "COVERAGE [$(COLOR_YELLOW)FINISHED$(COLOR_RESET)]"
endif
.PHONY: tests

qemu_clean:
	$(call if_qemu,$(call silent_rm,$(OUT)/qemu-$(QEMU_ARCH)))

qemu_chroot_install:
ifeq ($(USE_QEMU),1)
	$(QUIET)$(ECHO) "QEMU   Preparing qemu-$(QEMU_ARCH)"
	$(QUIET)cp -fu /usr/bin/qemu-$(QEMU_ARCH) $(OUT)/qemu-$(QEMU_ARCH)
	$(QUIET)chmod a+rx $(OUT)/qemu-$(QEMU_ARCH)
endif
.PHONY: qemu_clean qemu_chroot_install

# TODO(wad) Move to -L $(SYSROOT) and fakechroot when qemu-user
#           doesn't hang traversing /proc from SYSROOT.
QEMU_CMD =
ROOT_CMD = $(if $(filter 1,$(NEEDS_ROOT)),sudo , )
MOUNT_CMD = $(if $(filter 1,$(NEEDS_MOUNTS)),$(ROOT_CMD) mount, \#)
UMOUNT_CMD = $(if $(filter 1,$(NEEDS_MOUNTS)),$(ROOT_CMD) umount, \#)
QEMU_LDPATH = $(SYSROOT_LDPATH):/lib64:/lib:/usr/lib64:/usr/lib
ROOT_CMD_LDPATH = $(SYSROOT_LDPATH):$(SYSROOT)/lib64:
ROOT_CMD_LDPATH := $(ROOT_CMD_LDPATH):$(SYSROOT)/lib:$(SYSROOT)/usr/lib64:
ROOT_CMD_LDPATH := $(ROOT_CMD_LDPATH):$(SYSROOT)/usr/lib
ifeq ($(USE_QEMU),1)
  export QEMU_CMD = \
   sudo chroot $(SYSROOT) $(SYSROOT_OUT)qemu-$(QEMU_ARCH) \
   -drop-ld-preload \
   -E LD_LIBRARY_PATH="$(QEMU_LDPATH):$(patsubst $(OUT),,$(LD_DIRS))" \
   -E HOME="$(HOME)" --
  # USE_QEMU conditional function
  define if_qemu
    $(1)
  endef
else
  ROOT_CMD = $(if $(filter 1,$(NEEDS_ROOT)),sudo, ) \
    LD_LIBRARY_PATH="$(ROOT_CMD_LDPATH):$(LD_DIRS)"
  define if_qemu
    $(2)
  endef
endif

VALGRIND_CMD =
ifeq ($(VALGRIND),1)
  VALGRIND_CMD = /usr/bin/valgrind --tool=memcheck $(VALGRIND_ARGS) --
endif

define TEST_implementation
  $(QUIET)$(call TEST_setup)
  $(QUIET)$(call TEST_run)
  $(QUIET)$(call TEST_teardown)
  $(QUIET)exit $$(cat $(OUT)$(TARGET_OR_MEMBER).status.test)
endef

define TEST_setup
  @$(ECHO) -n "TEST		$(TARGET_OR_MEMBER) "
  @$(ECHO) "[$(COLOR_YELLOW)SETUP$(COLOR_RESET)]"
  $(QUIET)# Setup a target-specific results file
  $(QUIET)(echo 1 > $(OUT)$(TARGET_OR_MEMBER).status.test)
  $(QUIET)(echo > $(OUT)$(TARGET_OR_MEMBER).cleanup.test)
  $(QUIET)# No setup if we are not using QEMU
  $(QUIET)# TODO(wad) this is racy until we use a vfs namespace
  $(call if_qemu,\
    $(QUIET)sudo mkdir -p "$(SYSROOT)/proc" "$(SYSROOT)/dev")
  $(call if_qemu,\
    $(QUIET)$(MOUNT_CMD) --bind /proc "$(SYSROOT)/proc")
  $(call if_qemu,\
    $(QUIET)$(MOUNT_CMD) --bind /dev "$(SYSROOT)/dev")
  $(call if_qemu,\
    $(QUIET)(echo "$(UMOUNT_CMD) -l '$(SYSROOT)/proc'" \
             >> "$(OUT)$(TARGET_OR_MEMBER).cleanup.test"))
  $(call if_qemu,\
    $(QUIET)(echo "$(UMOUNT_CMD) -l '$(SYSROOT)/dev'" \
             >> "$(OUT)$(TARGET_OR_MEMBER).cleanup.test"))
endef

define TEST_teardown
  @$(ECHO) -n "TEST		$(TARGET_OR_MEMBER) "
  @$(ECHO) "[$(COLOR_YELLOW)TEARDOWN$(COLOR_RESET)]"
  $(call if_qemu, $(QUIET)$(SHELL) "$(OUT)$(TARGET_OR_MEMBER).cleanup.test")
endef

# Use GTEST_ARGS.[arch] if defined.
override GTEST_ARGS.real = \
 $(call if_qemu,$(GTEST_ARGS.qemu.$(QEMU_ARCH)),$(GTEST_ARGS.host.$(HOST_ARCH)))

define TEST_run
  @$(ECHO) -n "TEST		$(TARGET_OR_MEMBER) "
  @$(ECHO) "[$(COLOR_GREEN)RUN$(COLOR_RESET)]"
  $(QUIET)(echo 1 > "$(OUT)$(TARGET_OR_MEMBER).status.test")
  -($(ROOT_CMD) $(QEMU_CMD) $(VALGRIND_CMD) \
    "$(strip $(call if_qemu, $(SYSROOT_OUT),$(OUT))$(TARGET_OR_MEMBER))" \
      $(if $(filter-out 0,$(words $(GTEST_ARGS.real))),$(GTEST_ARGS.real),\
           $(GTEST_ARGS)) && \
    echo 0 > "$(OUT)$(TARGET_OR_MEMBER).status.test")
endef

# Recursive list reversal so that we get RMDIR_ON_CLEAN in reverse order.
define reverse
$(if $(1),$(call reverse,$(wordlist 2,$(words $(1)),$(1)))) $(firstword $(1))
endef

clean: qemu_clean
clean: CLEAN($(OUT)*.d) CLEAN($(OUT)*.o) CLEAN($(OUT)*.debug)
clean: CLEAN($(OUT)*.test) CLEAN($(OUT)*.depends)
clean: CLEAN($(OUT)*.gcno) CLEAN($(OUT)*.gcda) CLEAN($(OUT)*.gcov)
clean: CLEAN($(OUT)lcov-coverage.info) CLEAN($(OUT)lcov-html)

clean:
	$(QUIET)# Always delete the containing directory last.
	$(call silent_rmdir,$(OUT))

FORCE: ;
# Empty rule for use when no special targets are needed, like large_tests
NONE:

.PHONY: clean NONE valgrind NONE
.DEFAULT_GOAL  :=  all
# Don't let make blow away "intermediates"
.PRECIOUS: %.pic.o %.pie.o %.a %.pic.a %.pie.a %.test

# Start accruing build info
OUT_DIRS = $(OUT)
LD_DIRS = $(OUT)
SRC_DIRS = $(SRC)

include $(wildcard $(OUT)*.d)
SUBMODULE_DIRS = $(wildcard $(SRC)/*/module.mk)
include $(SUBMODULE_DIRS)


else  ## In duplicate inclusions of common.mk

# Get the current inclusion directory without a trailing slash
MODULE := $(patsubst %/,%, \
           $(dir $(lastword $(filter-out %common.mk,$(MAKEFILE_LIST)))))
MODULE := $(subst $(SRC)/,,$(MODULE))
MODULE_NAME := $(subst /,_,$(MODULE))
#VPATH := $(MODULE):$(VPATH)


# Depth first
$(eval OUT_DIRS += $(OUT)$(MODULE))
$(eval SRC_DIRS += $(OUT)$(MODULE))
$(eval LD_DIRS := $(LD_DIRS):$(OUT)$(MODULE))

# Add the defaults from this dir to rm_clean
clean: CLEAN($(OUT)$(MODULE)/*.d) CLEAN($(OUT)$(MODULE)/*.o)
clean: CLEAN($(OUT)$(MODULE)/*.debug) CLEAN($(OUT)$(MODULE)/*.test)
clean: CLEAN($(OUT)$(MODULE)/*.depends)
clean: CLEAN($(OUT)$(MODULE)/*.gcno) CLEAN($(OUT)$(MODULE)/*.gcda)
clean: CLEAN($(OUT)$(MODULE)/*.gcov) CLEAN($(OUT)lcov-coverage.info)
clean: CLEAN($(OUT)lcov-html)

$(info + submodule: $(MODULE_NAME))
# We must eval otherwise they may be dropped.
MODULE_C_OBJECTS = $(patsubst $(SRC)/$(MODULE)/%.c,$(MODULE)/%.o,\
  $(wildcard $(SRC)/$(MODULE)/*.c))
$(eval $(MODULE_NAME)_C_OBJECTS ?= $(MODULE_C_OBJECTS))
MODULE_CXX_OBJECTS = $(patsubst $(SRC)/$(MODULE)/%.cc,$(MODULE)/%.o,\
  $(wildcard $(SRC)/$(MODULE)/*.cc))
$(eval $(MODULE_NAME)_CXX_OBJECTS ?= $(MODULE_CXX_OBJECTS))

# Note, $(MODULE) is implicit in the path to the %.c.
# See $(C_OBJECTS) for more details.
# Register rules for the module objects.
$(eval $(call add_object_rules,$(MODULE_C_OBJECTS),CC,c,CFLAGS,$(SRC)/))
$(eval $(call add_object_rules,$(MODULE_CXX_OBJECTS),CXX,cc,CXXFLAGS,$(SRC)/))

# Continue recursive inclusion of module.mk files
SUBMODULE_DIRS = $(wildcard $(SRC)/$(MODULE)/*/module.mk)
include $(wildcard $(OUT)$(MODULE)/*.d)
include $(SUBMODULE_DIRS)

endif
endif  ## pass-to-subcall wrapper for relocating the call directory