-
Notifications
You must be signed in to change notification settings - Fork 19
/
BUILD.gn
2348 lines (2124 loc) · 80.2 KB
/
BUILD.gn
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
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
# Copyright (c) 2013 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
import("//build/config/android/config.gni")
import("//build/config/c++/c++.gni")
import("//build/config/chrome_build.gni")
import("//build/config/chromecast_build.gni")
import("//build/config/clang/clang.gni")
import("//build/config/compiler/compiler.gni")
import("//build/config/coverage/coverage.gni")
import("//build/config/host_byteorder.gni")
import("//build/config/sanitizers/sanitizers.gni")
import("//build/config/ui.gni")
import("//build/toolchain/cc_wrapper.gni")
import("//build/toolchain/toolchain.gni")
import("//build_overrides/build.gni")
if (current_cpu == "arm" || current_cpu == "arm64") {
import("//build/config/arm.gni")
}
if (current_cpu == "mipsel" || current_cpu == "mips64el" ||
current_cpu == "mips" || current_cpu == "mips64") {
import("//build/config/mips.gni")
}
if (is_mac) {
import("//build/config/mac/symbols.gni")
}
if (is_ios) {
import("//build/config/ios/ios_sdk.gni")
}
if (is_nacl) {
# To keep NaCl variables out of builds that don't include NaCl, all
# variables defined in nacl/config.gni referenced here should be protected by
# is_nacl conditions.
import("//build/config/nacl/config.gni")
}
declare_args() {
# Default to warnings as errors for default workflow, where we catch
# warnings with known toolchains. Allow overriding this e.g. for Chromium
# builds on Linux that could use a different version of the compiler.
# With GCC, warnings in no-Chromium code are always not treated as errors.
treat_warnings_as_errors = false #ANDREW
# Normally, Android builds are lightly optimized, even for debug builds, to
# keep binary size down. Setting this flag to true disables such optimization
android_full_debug = false
# Whether to use the binary binutils checked into third_party/binutils.
# These are not multi-arch so cannot be used except on x86 and x86-64 (the
# only two architectures that are currently checked in). Turn this off when
# you are using a custom toolchain and need to control -B in cflags.
linux_use_bundled_binutils =
linux_use_bundled_binutils_override && is_linux &&
(current_cpu == "x64" || current_cpu == "x86")
binutils_path = rebase_path("//third_party/binutils/Linux_x64/Release/bin",
root_build_dir)
# Compile in such a way as to make it possible for the profiler to unwind full
# stack frames. Setting this flag has a large effect on the performance of the
# generated code than just setting profiling, but gives the profiler more
# information to analyze.
# Requires profiling to be set to true.
enable_full_stack_frames_for_profiling = false
# When we are going to use gold we need to find it.
# This is initialized below, after use_gold might have been overridden.
gold_path = false
if (is_win) {
# Whether the VS xtree header has been patched to disable warning 4702. If
# it has, then we don't need to disable 4702 (unreachable code warning).
# The patch is preapplied to the internal toolchain and hence all bots.
msvs_xtree_patched = false
}
# Enable fatal linker warnings. Building Chromium with certain versions
# of binutils can cause linker warning.
# See: https://bugs.chromium.org/p/chromium/issues/detail?id=457359
fatal_linker_warnings = true
# Build with C++ RTTI enabled. Chromium builds without RTTI by default,
# but some sanitizers are known to require it, like CFI diagnostics
# and UBsan variants.
use_rtti = use_cfi_diag || is_ubsan_vptr || is_ubsan_security
# AFDO (Automatic Feedback Directed Optimizer) is a form of profile-guided
# optimization that GCC supports. It used by ChromeOS in their official
# builds. To use it, set auto_profile_path to the path to a file containing
# the needed gcov profiling data.
auto_profile_path = ""
# Optimize symbol files for maximizing goma cache hit rate. This is on by
# default when goma is enabled on Linux and Windows.
# But setting this to true may make it harder to debug binaries on Linux.
# See below reference for detail.
# https://chromium.googlesource.com/chromium/src/+/master/docs/linux_debugging.md#Source-level-debug-with-fdebug_compilation_dir
strip_absolute_paths_from_debug_symbols =
(is_linux || (is_win && use_lld)) && use_goma
# Allow projects that wish to stay on C++11 to override Chromium's default.
use_cxx11 = false
# Strip the debug info of symbols file in lib.unstripped to reduce size.
strip_debug_info = false
# Path to an AFDO profile to use while building with clang, if any. Empty
# implies none.
clang_sample_profile_path = ""
# Some configurations have default sample profiles. If this is true and
# clang_sample_profile_path is empty, we'll fall back to the default.
#
# We currently only have default profiles for Chromium in-tree, so we disable
# this by default for all downstream projects, since these profiles are likely
# nonsensical for said projects.
clang_use_default_sample_profile = build_with_chromium && is_official_build &&
(is_android || is_desktop_linux)
# Turn this on to have the compiler output extra timing information.
compiler_timing = false
# Set to true to pass --no-rosegment to lld. This is a workaround
# for a KI issue in Valgrind,
# https://bugs.kde.org/show_bug.cgi?id=384727
ro_segment_workaround_for_valgrind = false
# Turn this on to use ghash feature of lld for faster debug link on Windows.
# http://blog.llvm.org/2018/01/improving-link-time-on-windows-with.html
use_ghash = false
# Whether to enable ThinLTO optimizations. Turning ThinLTO optimizations on
# can substantially increase link time and binary size, but they generally
# also make binaries a fair bit faster.
#
# TODO(gbiv): We disable optimizations by default on most platforms because
# the space overhead is too great. We should use some mixture of profiles and
# optimization settings to better tune the size increase.
thin_lto_enable_optimizations = is_chromeos
}
declare_args() {
# C++11 may not be an option if Android test infrastructure is used.
use_cxx11_on_android = use_cxx11
}
declare_args() {
# Set to true to use icf, Identical Code Folding.
#
# icf=all is broken in older golds, see
# https://sourceware.org/bugzilla/show_bug.cgi?id=17704
# See also https://crbug.com/663886
# `linux_use_bundled_binutils` is to avoid breaking Linux distros which may
# still have a buggy gold.
# chromeos binutils has been patched with the fix, so always use icf there.
# The bug only affects x86 and x64, so we can still use ICF when targeting
# other architectures.
#
# lld doesn't have the bug.
use_icf = (is_posix || is_fuchsia) && !using_sanitizer &&
!use_clang_coverage && !(is_android && use_order_profiling) &&
(use_lld ||
(use_gold &&
((!is_android && linux_use_bundled_binutils) || is_chromeos ||
!(current_cpu == "x86" || current_cpu == "x64"))))
}
# Apply the default logic for these values if they were not set explicitly.
if (gold_path == false) {
if (use_gold) {
gold_path = rebase_path("//third_party/binutils/Linux_x64/Release/bin",
root_build_dir)
} else {
gold_path = ""
}
}
if (use_debug_fission == "default") {
use_debug_fission = is_debug && !is_android && !is_fuchsia && !is_win &&
(use_gold || use_lld) && cc_wrapper == ""
}
# default_include_dirs ---------------------------------------------------------
#
# This is a separate config so that third_party code (which would not use the
# source root and might have conflicting versions of some headers) can remove
# this and specify their own include paths.
config("default_include_dirs") {
include_dirs = [
"//",
root_gen_dir,
]
}
# compiler ---------------------------------------------------------------------
#
# Base compiler configuration.
#
# See also "runtime_library" below for related stuff and a discussion about
# where stuff should go. Put warning related stuff in the "warnings" config.
config("compiler") {
asmflags = []
cflags = []
cflags_c = []
cflags_cc = []
cflags_objc = []
cflags_objcc = []
ldflags = []
defines = []
configs = []
inputs = []
# System-specific flags. If your compiler flags apply to one of the
# categories here, add it to the associated file to keep this shared config
# smaller.
if (is_win) {
configs += [ "//build/config/win:compiler" ]
} else if (is_android) {
configs += [ "//build/config/android:compiler" ]
} else if (is_linux) {
configs += [ "//build/config/linux:compiler" ]
} else if (is_nacl) {
configs += [ "//build/config/nacl:compiler" ]
} else if (is_mac) {
configs += [ "//build/config/mac:compiler" ]
} else if (is_ios) {
configs += [ "//build/config/ios:compiler" ]
} else if (is_fuchsia) {
configs += [ "//build/config/fuchsia:compiler" ]
} else if (current_os == "aix") {
configs += [ "//build/config/aix:compiler" ]
}
configs += [
# See the definitions below.
":clang_revision",
":compiler_cpu_abi",
":compiler_codegen",
]
# In general, Windows is totally different, but all the other builds share
# some common GCC configuration.
if (!is_win) {
# Common POSIX compiler flags setup.
# --------------------------------
cflags += [ "-fno-strict-aliasing" ] # See http://crbug.com/32204
# Stack protection.
if (is_mac) {
# The strong variant of the stack protector significantly increases
# binary size, so only enable it in debug mode.
if (is_debug) {
cflags += [ "-fstack-protector-strong" ]
} else {
cflags += [ "-fstack-protector" ]
}
} else if ((is_posix && !is_chromeos && !is_nacl) || is_fuchsia) {
# TODO(phajdan.jr): Use -fstack-protector-strong when our gcc supports it.
# See also https://crbug.com/533294
cflags += [ "--param=ssp-buffer-size=4" ]
# The x86 toolchain currently has problems with stack-protector.
if (is_android && current_cpu == "x86") {
cflags += [ "-fno-stack-protector" ]
} else if (current_os != "aix") {
# Not available on aix.
cflags += [ "-fstack-protector" ]
}
}
# Linker warnings.
if (fatal_linker_warnings && !(is_chromeos && current_cpu == "arm") &&
!(is_android && use_order_profiling) && !is_mac && !is_ios &&
current_os != "aix") {
# TODO(jochen): Enable this on chromeos on arm. http://crbug.com/356580
# TODO(lizeb,pasko): Fix link errors when linking with order_profiling=1
# crbug.com/485542
ldflags += [ "-Wl,--fatal-warnings" ]
}
} else {
cflags += [
# Assume UTF-8 by default to avoid code page dependencies.
"/utf-8",
]
if (is_clang) {
# Don't look for includes in %INCLUDE%.
cflags += [ "/X" ]
}
}
# Eliminate build metadata (__DATE__, __TIME__ and __TIMESTAMP__) for
# deterministic build. See https://crbug.com/314403
if (!is_official_build) {
if (is_win && !is_clang) {
cflags += [
"/wd4117", # Trying to define or undefine a predefined macro.
"/D__DATE__=",
"/D__TIME__=",
"/D__TIMESTAMP__=",
]
} else {
cflags += [
"-Wno-builtin-macro-redefined",
"-D__DATE__=",
"-D__TIME__=",
"-D__TIMESTAMP__=",
]
}
}
if (is_clang && is_debug) {
# Allow comparing the address of references and 'this' against 0
# in debug builds. Technically, these can never be null in
# well-defined C/C++ and Clang can optimize such checks away in
# release builds, but they may be used in asserts in debug builds.
cflags_cc += [
"-Wno-undefined-bool-conversion",
"-Wno-tautological-undefined-compare",
]
}
# Non-Mac Posix and Fuchsia compiler flags setup.
# -----------------------------------
if ((is_posix && !(is_mac || is_ios)) || is_fuchsia) {
if (enable_profiling) {
if (!is_debug) {
cflags += [ "-g" ]
if (enable_full_stack_frames_for_profiling) {
cflags += [
"-fno-inline",
"-fno-optimize-sibling-calls",
]
}
}
}
if (is_official_build) {
# Explicitly pass --build-id to ld. Compilers used to always pass this
# implicitly but don't any more (in particular clang when built without
# ENABLE_LINKER_BUILD_ID=ON). The crash infrastructure does need a build
# id, so explicitly enable it in official builds. It's not needed in
# unofficial builds and computing it does slow down the link, so go with
# faster links in unofficial builds.
ldflags += [ "-Wl,--build-id=sha1" ]
}
if (!is_android) {
defines += [
# _FILE_OFFSET_BITS=64 should not be set on Android in order to maintain
# the behavior of the Android NDK from earlier versions.
# See https://android-developers.googleblog.com/2017/09/introducing-android-native-development.html
"_FILE_OFFSET_BITS=64",
"_LARGEFILE_SOURCE",
"_LARGEFILE64_SOURCE",
]
}
if (!is_nacl) {
if (exclude_unwind_tables) {
cflags += [
"-fno-unwind-tables",
"-fno-asynchronous-unwind-tables",
]
defines += [ "NO_UNWIND_TABLES" ]
} else {
cflags += [ "-funwind-tables" ]
}
}
}
# Linux/Android/Fuchsia common flags setup.
# ---------------------------------
if (is_linux || is_android || is_fuchsia) {
if (use_pic) {
cflags += [ "-fPIC" ]
ldflags += [ "-fPIC" ]
}
if (!is_clang) {
# Use pipes for communicating between sub-processes. Faster.
# (This flag doesn't do anything with Clang.)
cflags += [ "-pipe" ]
}
ldflags += [
"-Wl,-z,noexecstack",
"-Wl,-z,now",
"-Wl,-z,relro",
]
# Compiler instrumentation can introduce dependencies in DSOs to symbols in
# the executable they are loaded into, so they are unresolved at link-time.
if (!using_sanitizer && !is_safestack) {
ldflags += [
"-Wl,-z,defs",
"-Wl,--as-needed",
]
}
}
# Linux-specific compiler flags setup.
# ------------------------------------
if (is_android && is_clang) {
_rebased_android_toolchain_root =
rebase_path(android_toolchain_root, root_build_dir)
# Let clang find the linker in the NDK.
ldflags += [ "--gcc-toolchain=$_rebased_android_toolchain_root" ]
}
if (((is_posix || is_fuchsia) && use_lld) ||
(target_os == "chromeos" && is_android)) {
# NOTE: Some Chrome OS builds globally disable LLD, but they also build some
# targets against Android toolchains which should use LLD. Therefore we
# explicitly select LLD in these cases.
#
# TODO(https://crbug.com/837095): This should be cleaned up if/when LLD can
# work properly for Chrome OS builds.
ldflags += [ "-fuse-ld=lld" ]
if (current_cpu == "arm64") {
# Reduce the page size from 65536 in order to reduce binary size slightly
# by shrinking the alignment gap between segments. This also causes all
# segments to be mapped adjacently, which breakpad relies on.
ldflags += [ "-Wl,-z,max-page-size=4096" ]
}
} else if (use_gold) {
ldflags += [ "-fuse-ld=gold" ]
if (!is_android) {
# On Android, this isn't needed. gcc in the NDK knows to look next to
# it with -fuse-ld=gold, and clang gets a --gcc-toolchain flag passed
# above.
ldflags += [ "-B$gold_path" ]
if (linux_use_bundled_binutils) {
ldflags += [
# Experimentation found that using four linking threads
# saved ~20% of link time.
# https://groups.google.com/a/chromium.org/group/chromium-dev/browse_thread/thread/281527606915bb36
# Only apply this to the target linker, since the host
# linker might not be gold, but isn't used much anyway.
"-Wl,--threads",
"-Wl,--thread-count=4",
]
}
}
# TODO(thestig): Make this flag work with GN.
#if (!is_official_build && !is_chromeos && !(is_asan || is_lsan || is_tsan || is_msan)) {
# ldflags += [
# "-Wl,--detect-odr-violations",
# ]
#}
} else if (linux_use_bundled_binutils) {
# Gold is the default linker for the bundled binutils so we explicitly
# enable the bfd linker when use_gold is not set.
ldflags += [ "-fuse-ld=bfd" ]
}
if (use_icf) {
ldflags += [ "-Wl,--icf=all" ]
}
if (linux_use_bundled_binutils) {
cflags += [ "-B$binutils_path" ]
}
if (is_linux) {
cflags += [ "-pthread" ]
# Do not use the -pthread ldflag here since it becomes a no-op
# when using -nodefaultlibs, which would cause an unused argument
# error. "-lpthread" is added in //build/config:default_libs.
}
# Clang-specific compiler flags setup.
# ------------------------------------
if (is_clang) {
cflags += [ "-fcolor-diagnostics" ]
# Enable -fmerge-all-constants. This used to be the default in clang
# for over a decade. It makes clang non-conforming, but is fairly safe
# in practice and saves some binary size. We might want to consider
# disabling this (https://bugs.llvm.org/show_bug.cgi?id=18538#c13),
# but for now it looks like our build might rely on it
# (https://crbug.com/829795).
cflags += [ "-fmerge-all-constants" ]
}
if (use_lld) {
# TODO(thakis): Make the driver pass --color-diagnostics to the linker
# if -fcolor-diagnostics is passed to it, and pass -fcolor-diagnostics
# in ldflags instead.
if (is_win) {
# On Windows, we call the linker directly, instead of calling it through
# the driver.
ldflags += [ "--color-diagnostics" ]
} else {
ldflags += [ "-Wl,--color-diagnostics" ]
}
}
if (is_clang && !is_nacl && current_toolchain == host_toolchain &&
target_os != "chromeos") {
cflags += [
# TODO(hans): Remove this once Clang generates better optimized debug info
# by default. https://crbug.com/765793
"-Xclang",
"-mllvm",
"-Xclang",
"-instcombine-lower-dbg-declare=0",
]
}
# Print absolute paths in diagnostics. There is no precedent for doing this
# on Linux/Mac (GCC doesn't support it), but MSVC does this with /FC and
# Windows developers rely on it (crbug.com/636109) so only do this on Windows.
if (msvc_use_absolute_paths && is_clang && is_win) {
cflags += [ "-fdiagnostics-absolute-paths" ]
}
# Makes builds independent of absolute file path.
# Currently disabled for nacl since its toolchain lacks this flag (too old).
# TODO(zforman): Once nacl's toolchain is updated, remove check.
if (symbol_level != 0 && is_clang && !is_nacl && !is_mac && !is_ios &&
strip_absolute_paths_from_debug_symbols) {
# If debug option is given, clang includes $cwd in debug info by default.
# For such build, this flag generates reproducible obj files even we use
# different build directory like "out/feature_a" and "out/feature_b" if
# we build same files with same compile flag.
# Other paths are already given in relative, no need to normalize them.
cflags += [
"-Xclang",
"-fdebug-compilation-dir",
"-Xclang",
".",
]
if (is_win && use_lld) {
# Absolutize source file path for PDB.
ldflags += [ "/PDBSourcePath:" + rebase_path(root_build_dir) ]
}
}
# Tells the compiler not to use absolute paths when passing the default
# paths to the tools it invokes. We don't want this because we don't
# really need it and it can mess up the goma cache entries.
if (is_clang && !is_nacl) {
cflags += [ "-no-canonical-prefixes" ]
}
# C11/C++11 compiler flags setup.
# ---------------------------
if (is_linux || is_android || (is_nacl && is_clang) || current_os == "aix") {
if (target_os == "android") {
cxx11_override = use_cxx11_on_android
} else {
cxx11_override = use_cxx11
}
if (is_clang) {
standard_prefix = "c"
# Since we build with -std=c* and not -std=gnu*, _GNU_SOURCE will not be
# defined by the compiler. However, lots of code relies on the
# non-standard features that _GNU_SOURCE enables, so define it manually.
defines += [ "_GNU_SOURCE" ]
if (is_nacl) {
# Undefine __STRICT_ANSI__ to get non-standard features which would
# otherwise not be enabled by NaCl's sysroots.
cflags += [ "-U__STRICT_ANSI__" ]
}
} else {
# Gcc does not support ##__VA_ARGS__ when in standards-conforming mode,
# but we use this feature in several places in Chromium.
# TODO(thomasanderson): Replace usages of ##__VA_ARGS__ with the
# standard-compliant __VA_OPT__ added by C++20, and switch the gcc build
# to -std=c*.
standard_prefix = "gnu"
}
cflags_c += [ "-std=${standard_prefix}11" ]
if (cxx11_override) {
# Override Chromium's default for projects that wish to stay on C++11.
cflags_cc += [ "-std=${standard_prefix}++11" ]
} else {
cflags_cc += [ "-std=${standard_prefix}++14" ]
}
} else if (!is_win && !is_nacl) {
if (target_os == "android") {
cxx11_override = use_cxx11_on_android
} else {
cxx11_override = use_cxx11
}
# TODO(mcgrathr) - the NaCl GCC toolchain doesn't support either gnu11/gnu++11
# or c11/c++11; we technically don't need this toolchain any more, but there
# are still a few buildbots using it, so until those are turned off
# we need the !is_nacl clause and the (is_nacl && is_clang) clause, above.
cflags_c += [ "-std=c11" ]
if (cxx11_override) {
cflags_cc += [ "-std=c++11" ]
} else {
cflags_cc += [ "-std=c++14" ]
}
}
if (is_mac) {
# The system libc++ on Mac doesn't have aligned allocation in C++17.
defines += [ "_LIBCPP_HAS_NO_ALIGNED_ALLOCATION" ]
cflags_cc += [ "-stdlib=libc++" ]
ldflags += [ "-stdlib=libc++" ]
}
# Add flags for link-time optimization. These flags enable
# optimizations/transformations that require whole-program visibility at link
# time, so they need to be applied to all translation units, and we may end up
# with miscompiles if only part of the program is compiled with LTO flags. For
# that reason, we cannot allow targets to enable or disable these flags, for
# example by disabling the optimize configuration.
# TODO(pcc): Make this conditional on is_official_build rather than on gn
# flags for specific features.
if (!is_debug && use_thin_lto &&
(current_toolchain == default_toolchain ||
(is_android && defined(android_secondary_abi_toolchain) &&
current_toolchain == android_secondary_abi_toolchain))) {
assert(use_lld || target_os == "chromeos",
"gold plugin only supported with ChromeOS")
cflags += [ "-flto=thin" ]
if (thin_lto_enable_optimizations) {
lto_opt_level = 2
} else {
lto_opt_level = 0
}
if (is_win) {
# This is a straight translation of the non-Windows flags below,
# except we do not use the ThinLTO cache, which leaks temporary
# files on Windows (https://crbug.com/871962).
ldflags += [
"/opt:lldlto=" + lto_opt_level,
"/opt:lldltojobs=8",
]
} else {
ldflags += [ "-flto=thin" ]
# Limit the parallelism to avoid too aggressive competition between
# linker jobs. This is still suboptimal to a potential dynamic
# resource allocation scheme, but should be good enough.
if (use_lld) {
# Limit the size of the ThinLTO cache to the lesser of 10% of available disk
# space, 10GB and 100000 files.
cache_policy =
"cache_size=10%:cache_size_bytes=10g:cache_size_files=100000"
ldflags += [
"-Wl,--thinlto-jobs=8",
"-Wl,--thinlto-cache-dir=" +
rebase_path("$root_out_dir/thinlto-cache", root_build_dir),
"-Wl,--thinlto-cache-policy,$cache_policy",
]
} else {
ldflags += [ "-Wl,-plugin-opt,jobs=8" ]
}
if (use_lld) {
ldflags += [ "-Wl,--lto-O" + lto_opt_level ]
if (thin_lto_enable_optimizations) {
if (is_android) {
# TODO(gbiv): We ideally shouldn't need to specify this; ThinLTO
# should be able to better manage binary size increases on its own.
ldflags += [
"-Wl,-mllvm",
"-Wl,-import-instr-limit=5",
]
}
}
} else {
not_needed([ "lto_opt_level" ])
}
}
# TODO(pcc): Re-enable this flag on Android. This will require libc++ to be
# built with ThinLTO (see https://crbug.com/767901) as well as the GVR shim.
if (!is_android) {
cflags += [ "-fwhole-program-vtables" ]
if (!is_win) {
ldflags += [ "-fwhole-program-vtables" ]
}
}
# Work-around for http://openradar.appspot.com/20356002
if (is_mac) {
ldflags += [ "-Wl,-all_load" ]
}
# This flag causes LTO to create an .ARM.attributes section with the correct
# architecture. This is necessary because LLD will refuse to link a program
# unless the architecture revision in .ARM.attributes is sufficiently new.
# TODO(pcc): The contents of .ARM.attributes should be based on the
# -march flag passed at compile time (see llvm.org/pr36291).
if (current_cpu == "arm") {
ldflags += [ "-march=$arm_arch" ]
}
}
if (compiler_timing) {
if (is_clang) {
if (is_win) {
cflags += [ "-Xclang" ]
}
cflags += [ "-ftime-report" ]
} else if (is_win) {
cflags += [
# "Documented" here:
# http://aras-p.info/blog/2017/10/23/Best-unknown-MSVC-flag-d2cgsummary/
"/d2cgsummary",
]
}
}
# Pass flag to LLD to work around issue in Valgrind related to
# location of debug symbols.
if (use_lld && ro_segment_workaround_for_valgrind) {
ldflags += [ "-Wl,--no-rosegment" ]
}
# This flag enforces that member pointer base types are complete. It helps
# prevent us from running into problems in the Microsoft C++ ABI (see
# https://crbug.com/847724).
# ANDREW
#if (is_clang && !is_nacl && target_os != "chromeos" && !use_xcode_clang &&
# (is_win || use_custom_libcxx)) {
# cflags += [ "-fcomplete-member-pointers" ]
#}
# Pass the same C/C++ flags to the objective C/C++ compiler.
cflags_objc += cflags_c
cflags_objcc += cflags_cc
# Assign any flags set for the C compiler to asmflags so that they are sent
# to the assembler. The Windows assembler takes different types of flags
# so only do so for posix platforms.
if (is_posix || is_fuchsia) {
asmflags += cflags
asmflags += cflags_c
}
}
# This provides the basic options to select the target CPU and ABI.
# It is factored out of "compiler" so that special cases can use this
# without using everything that "compiler" brings in. Options that
# tweak code generation for a particular CPU do not belong here!
# See "compiler_codegen", below.
config("compiler_cpu_abi") {
cflags = []
ldflags = []
defines = []
if ((is_posix && !(is_mac || is_ios)) || is_fuchsia) {
# CPU architecture. We may or may not be doing a cross compile now, so for
# simplicity we always explicitly set the architecture.
if (current_cpu == "x64") {
cflags += [
"-m64",
"-march=x86-64",
]
ldflags += [ "-m64" ]
} else if (current_cpu == "x86") {
cflags += [ "-m32" ]
ldflags += [ "-m32" ]
if (!is_nacl) {
cflags += [
"-msse2",
"-mfpmath=sse",
"-mmmx",
]
}
} else if (current_cpu == "arm") {
if (is_clang && !is_android && !is_nacl) {
cflags += [ "--target=arm-linux-gnueabihf" ]
ldflags += [ "--target=arm-linux-gnueabihf" ]
}
if (!is_nacl) {
cflags += [
"-march=$arm_arch",
"-mfloat-abi=$arm_float_abi",
]
}
if (arm_tune != "") {
cflags += [ "-mtune=$arm_tune" ]
}
} else if (current_cpu == "arm64") {
if (is_clang && !is_android && !is_nacl && !is_fuchsia) {
cflags += [ "--target=aarch64-linux-gnu" ]
ldflags += [ "--target=aarch64-linux-gnu" ]
}
} else if (current_cpu == "mipsel" && !is_nacl) {
ldflags += [ "-Wl,--hash-style=sysv" ]
if (custom_toolchain == "") {
if (is_clang) {
if (is_android) {
cflags += [ "--target=mipsel-linux-android" ]
ldflags += [ "--target=mipsel-linux-android" ]
} else {
cflags += [ "--target=mipsel-linux-gnu" ]
ldflags += [ "--target=mipsel-linux-gnu" ]
}
} else {
cflags += [ "-EL" ]
ldflags += [ "-EL" ]
}
}
if (mips_arch_variant == "r6") {
cflags += [ "-mno-odd-spreg" ]
ldflags += [ "-mips32r6" ]
if (is_clang) {
cflags += [
"-march=mipsel",
"-mcpu=mips32r6",
]
} else {
cflags += [
"-mips32r6",
"-Wa,-mips32r6",
]
if (is_android) {
ldflags += [ "-Wl,-melf32ltsmip" ]
}
}
if (mips_use_msa == true) {
cflags += [
"-mmsa",
"-mfp64",
]
}
} else if (mips_arch_variant == "r2") {
ldflags += [ "-mips32r2" ]
if (is_clang) {
cflags += [
"-march=mipsel",
"-mcpu=mips32r2",
]
} else {
cflags += [
"-mips32r2",
"-Wa,-mips32r2",
]
if (mips_float_abi == "hard" && mips_fpu_mode != "") {
cflags += [ "-m$mips_fpu_mode" ]
}
}
} else if (mips_arch_variant == "r1") {
ldflags += [ "-mips32" ]
if (is_clang) {
cflags += [
"-march=mipsel",
"-mcpu=mips32",
]
} else {
cflags += [
"-mips32",
"-Wa,-mips32",
]
}
} else if (mips_arch_variant == "loongson3") {
defines += [ "_MIPS_ARCH_LOONGSON" ]
cflags += [
"-march=loongson3a",
"-mno-branch-likely",
"-Wa,-march=loongson3a",
]
}
if (mips_dsp_rev == 1) {
cflags += [ "-mdsp" ]
} else if (mips_dsp_rev == 2) {
cflags += [ "-mdspr2" ]
}
cflags += [ "-m${mips_float_abi}-float" ]
} else if (current_cpu == "mips" && !is_nacl) {
ldflags += [ "-Wl,--hash-style=sysv" ]
if (custom_toolchain == "") {
if (is_clang) {
cflags += [ "--target=mips-linux-gnu" ]
ldflags += [ "--target=mips-linux-gnu" ]
} else {
cflags += [ "-EB" ]
ldflags += [ "-EB" ]
}
}
if (mips_arch_variant == "r6") {
cflags += [
"-mips32r6",
"-Wa,-mips32r6",
]
if (mips_use_msa == true) {
cflags += [
"-mmsa",
"-mfp64",
]
}
} else if (mips_arch_variant == "r2") {
cflags += [
"-mips32r2",
"-Wa,-mips32r2",
]
if (mips_float_abi == "hard" && mips_fpu_mode != "") {
cflags += [ "-m$mips_fpu_mode" ]
}
} else if (mips_arch_variant == "r1") {
cflags += [
"-mips32",
"-Wa,-mips32",
]
}
if (mips_dsp_rev == 1) {
cflags += [ "-mdsp" ]
} else if (mips_dsp_rev == 2) {
cflags += [ "-mdspr2" ]
}
cflags += [ "-m${mips_float_abi}-float" ]
} else if (current_cpu == "mips64el") {
cflags += [ "-D__SANE_USERSPACE_TYPES__" ]
ldflags += [ "-Wl,--hash-style=sysv" ]
if (custom_toolchain == "") {
if (is_clang) {
if (is_android) {
cflags += [ "--target=mips64el-linux-android" ]
ldflags += [ "--target=mips64el-linux-android" ]
} else {
cflags += [ "--target=mips64el-linux-gnuabi64" ]
ldflags += [ "--target=mips64el-linux-gnuabi64" ]
}
} else {
cflags += [
"-EL",
"-mabi=64",
]
ldflags += [
"-EL",
"-mabi=64",
]
}
}
if (mips_arch_variant == "r6") {
if (is_clang) {
cflags += [
"-march=mips64el",
"-mcpu=mips64r6",
]
} else {
cflags += [
"-mips64r6",
"-Wa,-mips64r6",
]
ldflags += [ "-mips64r6" ]
}
if (mips_use_msa == true) {
cflags += [
"-mmsa",
"-mfp64",
]
}
} else if (mips_arch_variant == "r2") {
ldflags += [ "-mips64r2" ]
if (is_clang) {
cflags += [
"-march=mips64el",
"-mcpu=mips64r2",
]
} else {
cflags += [
"-mips64r2",
"-Wa,-mips64r2",
]
}
} else if (mips_arch_variant == "loongson3") {
defines += [ "_MIPS_ARCH_LOONGSON" ]
cflags += [
"-march=loongson3a",
"-mno-branch-likely",
"-Wa,-march=loongson3a",
]
}
} else if (current_cpu == "mips64") {
ldflags += [ "-Wl,--hash-style=sysv" ]
if (custom_toolchain == "") {
if (is_clang) {
cflags += [ "--target=mips64-linux-gnuabi64" ]
ldflags += [ "--target=mips64-linux-gnuabi64" ]