aboutsummaryrefslogtreecommitdiffstats
path: root/gcc-4.4.0/gcc/common.opt
blob: 7fe65fe39c4be37432e7c97581710c5ae27bf78a (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
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
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
; Options for the language- and target-independent parts of the compiler.

; Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008, 2009
; Free Software Foundation, Inc.
;
; This file is part of GCC.
;
; GCC is free software; you can redistribute it and/or modify it under
; the terms of the GNU General Public License as published by the Free
; Software Foundation; either version 3, or (at your option) any later
; version.
;
; GCC is distributed in the hope that it will be useful, but WITHOUT ANY
; WARRANTY; without even the implied warranty of MERCHANTABILITY or
; FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
; for more details.
;
; You should have received a copy of the GNU General Public License
; along with GCC; see the file COPYING3.  If not see
; <http://www.gnu.org/licenses/>.

; See the GCC internals manual (options.texi) for a description of this file's format.

; Please try to keep this file in ASCII collating order.

-help
Common
Display this information

-help=
Common Report Joined
--help=<class>	Display descriptions of a specific class of options.  <class> is one or more of optimizers, target, warnings, undocumented, params

-target-help
Common
Alias for --help=target

;; The following four entries are to work around the gcc driver
;; program's insatiable desire to turn options starting with a
;; double dash (--) into options starting with a dash f (-f).
fhelp
Common Var(help_flag)

fhelp=
Common Joined

ftarget-help
Common

fversion
Common

-param
Common Separate
--param <param>=<value>	Set parameter <param> to value.  See below for a complete list of parameters

-version
Common

G
Common Joined Separate UInteger
-G<number>	Put global and static data smaller than <number> bytes into a special section (on some targets)

O
Common JoinedOrMissing Optimization
-O<number>	Set optimization level to <number>

Os
Common Optimization
Optimize for space rather than speed

W
Common RejectNegative
This switch is deprecated; use -Wextra instead

Waggregate-return
Common Var(warn_aggregate_return) Warning
Warn about returning structures, unions or arrays

Warray-bounds
Common Var(warn_array_bounds) Warning
Warn if an array is accessed out of bounds

Wattributes
Common Var(warn_attributes) Init(1) Warning
Warn about inappropriate attribute usage

Wcast-align
Common Var(warn_cast_align) Warning
Warn about pointer casts which increase alignment

Wdeprecated-declarations
Common Var(warn_deprecated_decl) Init(1) Warning
Warn about uses of __attribute__((deprecated)) declarations

Wdisabled-optimization
Common Var(warn_disabled_optimization) Warning
Warn when an optimization pass is disabled

Werror
Common Var(warnings_are_errors)
Treat all warnings as errors

Werror=
Common Joined
Treat specified warning as error

Wextra
Common Warning
Print extra (possibly unwanted) warnings

Wfatal-errors
Common Var(flag_fatal_errors)
Exit on the first error occurred

Wframe-larger-than=
Common RejectNegative Joined UInteger
-Wframe-larger-than=<number> Warn if a function's stack frame requires more than <number> bytes

Winline
Common Var(warn_inline) Warning
Warn when an inlined function cannot be inlined

Wlarger-than-
Common RejectNegative Joined UInteger Warning

Wlarger-than=
Common RejectNegative Joined UInteger Warning
-Wlarger-than=<number>	Warn if an object is larger than <number> bytes

Wlogical-op
Common Warning Var(warn_logical_op)
Warn when a logical operator is suspicously always evaluating to true or false

Wunsafe-loop-optimizations
Common Var(warn_unsafe_loop_optimizations) Warning
Warn if the loop cannot be optimized due to nontrivial assumptions.

Wmissing-noreturn
Common Var(warn_missing_noreturn) Warning
Warn about functions which might be candidates for __attribute__((noreturn))

Wmudflap
Common Var(warn_mudflap) Init(1) Warning
Warn about constructs not instrumented by -fmudflap

Woverflow
Common Var(warn_overflow) Init(1) Warning
Warn about overflow in arithmetic expressions

Wpacked
Common Var(warn_packed) Warning
Warn when the packed attribute has no effect on struct layout

Wpadded
Common Var(warn_padded) Warning
Warn when padding is required to align structure members

Wripa-opt-mismatch
Common Var(warn_ripa_opt_mismatch) Warning
Warn if primary and auxiliary modules have mismatched command line options

Wshadow
Common Var(warn_shadow) Warning
Warn when one local variable shadows another

Wstack-protector
Common Var(warn_stack_protect) Warning
Warn when not issuing stack smashing protection for some reason

Wstrict-aliasing
Common Warning
Warn about code which might break strict aliasing rules

Wstrict-aliasing=
Common Joined UInteger Var(warn_strict_aliasing) Init(-1) Warning
Warn about code which might break strict aliasing rules

Wstrict-overflow
Common Warning
Warn about optimizations that assume that signed overflow is undefined

Wstrict-overflow=
Common Joined UInteger Var(warn_strict_overflow) Init(-1) Warning
Warn about optimizations that assume that signed overflow is undefined

Wswitch
Common Var(warn_switch) Warning
Warn about enumerated switches, with no default, missing a case

Wswitch-default
Common Var(warn_switch_default) Warning
Warn about enumerated switches missing a \"default:\" statement

Wswitch-enum
Common Var(warn_switch_enum) Warning
Warn about all enumerated switches missing a specific case

Wsystem-headers
Common Var(warn_system_headers) Warning
Do not suppress warnings from system headers

Wthread-safety
Common Var(warn_thread_safety) Warning
Warn about potential thread safety issues when the code is annotated with thread safety attributes

Wthread-unguarded-var
Common Var(warn_thread_unguarded_var) Init(1) Warning
Warn about shared variables not properly protected by locks specified in the attributes

Wthread-unguarded-func
Common Var(warn_thread_unguarded_func) Init(1) Warning
Warn about function calls not properly protected by locks specified in the attributes

Wthread-mismatched-lock-order
Common Var(warn_thread_mismatched_lock_order) Init(1) Warning
Warn about lock acquisition order inconsistent with what specified in the attributes

Wthread-mismatched-lock-acq-rel
Common Var(warn_thread_mismatched_lock_acq_rel) Init(1) Warning
Warn about mismatched lock acquisition and release

Wthread-reentrant-lock
Common Var(warn_thread_reentrant_lock) Init(1) Warning
Warn about a lock being acquired recursively

Wthread-unsupported-lock-name
Common Var(warn_unsupported_lock_name) Init(0) Warning
Warn about uses of unsupported lock names in attributes

Wtype-limits
Common Var(warn_type_limits) Init(-1) Warning
Warn if a comparison is always true or always false due to the limited range of the data type

Wuninitialized
Common Var(warn_uninitialized) Warning
Warn about uninitialized automatic variables

Wunreachable-code
Common Var(warn_notreached) Warning
Warn about code that will never be executed

Wunused
Common Var(warn_unused) Init(0) Warning
Enable all -Wunused- warnings

Wunused-function
Common Var(warn_unused_function) Init(-1) Warning
Warn when a function is unused

Wunused-label
Common Var(warn_unused_label) Init(-1) Warning
Warn when a label is unused

Wunused-parameter
Common Var(warn_unused_parameter) Init(-1) Warning
Warn when a function parameter is unused

Wunused-value
Common Var(warn_unused_value) Init(-1) Warning
Warn when an expression value is unused

Wunused-variable
Common Var(warn_unused_variable) Init(-1) Warning
Warn when a variable is unused

Wcoverage-mismatch
Common RejectNegative Var(warn_coverage_mismatch) Warning
Warn instead of error in case profiles in -fprofile-use do not match

aux-info
Common Separate
-aux-info <file>	Emit declaration information into <file>

aux-info=
Common Joined

auxbase
Common Separate

auxbase-strip
Common Separate

d
Common Joined
-d<letters>	Enable dumps from specific passes of the compiler

dumpbase
Common Separate
-dumpbase <file>	Set the file basename to be used for dumps

; The version of the C++ ABI in use.  The following values are allowed:
;
; 0: The version of the ABI believed most conformant with the C++ ABI
;    specification.  This ABI may change as bugs are discovered and fixed.
;    Therefore, 0 will not necessarily indicate the same ABI in different
;    versions of G++.
;
; 1: The version of the ABI first used in G++ 3.2.
;
; 2: The version of the ABI first used in G++ 3.4.
;
; Additional positive integers will be assigned as new versions of
; the ABI become the default version of the ABI.
fabi-version=
Common Joined UInteger Var(flag_abi_version) Init(2)

falign-functions
Common Report Var(align_functions,0) Optimization UInteger
Align the start of functions

falign-functions=
Common RejectNegative Joined UInteger

falign-jumps
Common Report Var(align_jumps,0) Optimization UInteger
Align labels which are only reached by jumping

falign-jumps=
Common RejectNegative Joined UInteger

falign-labels
Common Report Var(align_labels,0) Optimization UInteger
Align all labels

falign-labels=
Common RejectNegative Joined UInteger

falign-loops
Common Report Var(align_loops) Optimization UInteger
Align the start of loops

falign-loops=
Common RejectNegative Joined UInteger

; This flag is only tested if alias checking is enabled.
; 0 if pointer arguments may alias each other.  True in C.
; 1 if pointer arguments may not alias each other but may alias
;   global variables.
; 2 if pointer arguments may not alias each other and may not
;   alias global variables.
; 3 if pointer arguments may not alias anything.  True in Fortran.
;   Set by the front end.
fargument-alias
Common Report Var(flag_argument_noalias,0) Optimization
Specify that arguments may alias each other and globals

fargument-noalias
Common Report Var(flag_argument_noalias,1) VarExists Optimization
Assume arguments may alias globals but not each other

fargument-noalias-global
Common Report Var(flag_argument_noalias,2) VarExists Optimization
Assume arguments alias neither each other nor globals

fargument-noalias-anything
Common Report Var(flag_argument_noalias,3) VarExists Optimization
Assume arguments alias no other storage

fasynchronous-unwind-tables
Common Report Var(flag_asynchronous_unwind_tables) Optimization
Generate unwind tables that are exact at each instruction boundary

fauto-inc-dec
Common Report Var(flag_auto_inc_dec) Init(1)
Generate auto-inc/dec instructions

; -fcheck-bounds causes gcc to generate array bounds checks.
; For C, C++ and ObjC: defaults off.
; For Java: defaults to on.
; For Fortran: defaults to off.
fbounds-check
Common Report Var(flag_bounds_check)
Generate code to check bounds before indexing arrays

fbranch-count-reg
Common Report Var(flag_branch_on_count_reg) Init(1) Optimization
Replace add, compare, branch with branch on count register

fbranch-probabilities
Common Report Var(flag_branch_probabilities) Optimization
Use profiling information for branch probabilities

fbranch-target-load-optimize
Common Report Var(flag_branch_target_load_optimize) Optimization
Perform branch target load optimization before prologue / epilogue threading

fbranch-target-load-optimize2
Common Report Var(flag_branch_target_load_optimize2) Optimization
Perform branch target load optimization after prologue / epilogue threading

fbtr-bb-exclusive
Common Report Var(flag_btr_bb_exclusive) Optimization
Restrict target load migration not to re-use registers in any basic block

fcall-saved-
Common Joined RejectNegative
-fcall-saved-<register>	Mark <register> as being preserved across functions

fcall-used-
Common Joined RejectNegative
-fcall-used-<register>	Mark <register> as being corrupted by function calls

; Nonzero for -fcaller-saves: allocate values in regs that need to
; be saved across function calls, if that produces overall better code.
; Optional now, so people can test it.
fcaller-saves
Common Report Var(flag_caller_saves) Optimization
Save registers around function calls

fcheck-data-deps
Common Report Var(flag_check_data_deps)
Compare the results of several data dependence analyzers.

fcommon
Common Report Var(flag_no_common,0) Optimization
Do not put uninitialized globals in the common section

fconserve-stack
Common Var(flag_conserve_stack) Optimization
Do not perform optimizations increasing noticeably stack usage

fcprop-registers
Common Report Var(flag_cprop_registers) Optimization
Perform a register copy-propagation optimization pass

fcrossjumping
Common Report Var(flag_crossjumping) Optimization
Perform cross-jumping optimization

fcse-follow-jumps
Common Report Var(flag_cse_follow_jumps) Optimization
When running CSE, follow jumps to their targets

fcse-skip-blocks
Common Report Var(flag_cse_skip_blocks) Optimization
When running CSE, follow conditional jumps

fcx-limited-range
Common Report Var(flag_cx_limited_range) Optimization
Omit range reduction step when performing complex division

fcx-fortran-rules
Common Report Var(flag_cx_fortran_rules) Optimization
Complex multiplication and division follow Fortran rules

fdata-sections
Common Report Var(flag_data_sections) Optimization
Place data items into their own section

fdbg-cnt-list
Common Report
List all available debugging counters with their limits and counts.

fdbg-cnt=
Common RejectNegative Joined
-fdbg-cnt=<counter>:<limit>[,<counter>:<limit>,...]    Set the debug counter limit.   

fdebug-prefix-map=
Common Joined RejectNegative
Map one directory name to another in debug information

; Nonzero for -fdefer-pop: don't pop args after each function call
; instead save them up to pop many calls' args with one insns.
fdefer-pop
Common Report Var(flag_defer_pop) Optimization
Defer popping functions args from stack until later

fdelayed-branch
Common Report Var(flag_delayed_branch) Optimization
Attempt to fill delay slots of branch instructions

fdelete-null-pointer-checks
Common Report Var(flag_delete_null_pointer_checks) Optimization
Delete useless null pointer checks

fdiagnostics-show-location=
Common Joined RejectNegative
-fdiagnostics-show-location=[once|every-line]	How often to emit source location at the beginning of line-wrapped diagnostics

fdiagnostics-show-option
Common
Amend appropriate diagnostic messages with the command line option that controls them

fdominance-check
Common Report Var(flag_enable_dom_check) Init(0) Optimization
Check dominance information consistency after incremental update

fdump-
Common Joined RejectNegative
-fdump-<type>	Dump various compiler internals to a file

fdump-noaddr
Common Report Var(flag_dump_noaddr)
Suppress output of addresses in debugging dumps

fdump-unnumbered
Common Report Var(flag_dump_unnumbered) VarExists
Suppress output of instruction numbers, line number notes and addresses in debugging dumps

fdwarf2-cfi-asm
Common Report Var(flag_dwarf2_cfi_asm) Init(HAVE_GAS_CFI_DIRECTIVE)
Enable CFI tables via GAS assembler directives.

fripa
Common Report Var(flag_dyn_ipa)
Perform Dynamic Inter-Procedural Analysis.

fripa-disallow-opt-mismatch
Common Report Var(flag_ripa_disallow_opt_mismatch)
Don't import an auxiliary module if the command line options mismatch with the primary module

fripa-verbose
Common Report Var(flag_ripa_verbose)
Enable verbose informational messages for LIPO compilation

fearly-inlining
Common Report Var(flag_early_inlining) Init(1) Optimization
Perform early inlining

feliminate-dwarf2-dups
Common Report Var(flag_eliminate_dwarf2_dups)
Perform DWARF2 duplicate elimination

feliminate-unused-debug-symbols
Common Report Var(flag_debug_only_used_symbols)
Perform unused type elimination in debug info

feliminate-unused-debug-types
Common Report Var(flag_eliminate_unused_debug_types) Init(1)
Perform unused type elimination in debug info

femit-class-debug-always
Common Report Var(flag_emit_class_debug_always) Init(0)
Do not suppress C++ class debug information.

fenable-icf-debug
Common Report Var(flag_enable_icf_debug)
Generate debug information to support Identical Code Folding (ICF)

fexceptions
Common Report Var(flag_exceptions) Optimization
Enable exception handling

fexpensive-optimizations
Common Report Var(flag_expensive_optimizations) Optimization
Perform a number of minor, expensive optimizations

ffast-math
Common

ffinite-math-only
Common Report Var(flag_finite_math_only) Optimization
Assume no NaNs or infinities are generated

ffixed-
Common Joined RejectNegative
-ffixed-<register>	Mark <register> as being unavailable to the compiler

ffloat-store
Common Report Var(flag_float_store) Optimization
Don't allocate floats and doubles in extended-precision registers

fforce-addr
Common
Does nothing.  Preserved for backward compatibility.

fforward-propagate
Common Report Var(flag_forward_propagate) Optimization
Perform a forward propagation pass on RTL

; Nonzero means don't put addresses of constant functions in registers.
; Used for compiling the Unix kernel, where strange substitutions are
; done on the assembly output.
ffunction-cse
Common Report Var(flag_no_function_cse,0)
Allow function addresses to be held in registers

ffunction-sections
Common Report Var(flag_function_sections)
Place each function into its own section

fgcse
Common Report Var(flag_gcse) Optimization
Perform global common subexpression elimination

fgcse-lm
Common Report Var(flag_gcse_lm) Init(1) Optimization
Perform enhanced load motion during global common subexpression elimination

fgcse-sm
Common Report Var(flag_gcse_sm) Init(0) Optimization
Perform store motion after global common subexpression elimination

fgcse-las
Common Report Var(flag_gcse_las) Init(0) Optimization
Perform redundant load after store elimination in global common subexpression
elimination

fgcse-after-reload
Common Report Var(flag_gcse_after_reload) Optimization
Perform global common subexpression elimination after register allocation
has finished

; This option is not documented yet as its semantics will change.
fgraphite
Common Report Var(flag_graphite)
Enable in and out of Graphite representation

floop-strip-mine
Common Report Var(flag_loop_strip_mine) Optimization
Enable Loop Strip Mining transformation

floop-interchange
Common Report Var(flag_loop_interchange) Optimization
Enable Loop Interchange transformation

floop-block
Common Report Var(flag_loop_block) Optimization
Enable Loop Blocking transformation

; This option is not documented as it does not perform any useful optimization.
fgraphite-identity
Common Report Var(flag_graphite_identity) Optimization
Enable Graphite Identity transformation

fguess-branch-probability
Common Report Var(flag_guess_branch_prob) Optimization
Enable guessing of branch probabilities

; Nonzero means ignore `#ident' directives.  0 means handle them.
; Generate position-independent code for executables if possible
; On SVR4 targets, it also controls whether or not to emit a
; string identifying the compiler.
fident
Common Report Var(flag_no_ident,0)
Process #ident directives

fif-conversion
Common Report Var(flag_if_conversion) Optimization
Perform conversion of conditional jumps to branchless equivalents

fif-conversion2
Common Report Var(flag_if_conversion2) Optimization
Perform conversion of conditional jumps to conditional execution

; -finhibit-size-directive inhibits output of .size for ELF.
; This is used only for compiling crtstuff.c,
; and it may be extended to other effects
; needed for crtstuff.c on other systems.
finhibit-size-directive
Common Report Var(flag_inhibit_size_directive)
Do not generate .size directives

findirect-inlining
Common Report Var(flag_indirect_inlining)
Perform indirect inlining

; Nonzero means that functions declared `inline' will be treated
; as `static'.  Prevents generation of zillions of copies of unused
; static inline functions; instead, `inlines' are written out
; only when actually used.  Used in conjunction with -g.  Also
; does the right thing with #pragma interface.
finline
Common Report Var(flag_no_inline,0) Init(0)
Pay attention to the \"inline\" keyword

finline-small-functions
Common Report Var(flag_inline_small_functions) Optimization
Integrate simple functions into their callers when code size is known to not growth

finline-functions
Common Report Var(flag_inline_functions) Optimization
Integrate simple functions into their callers

finline-functions-called-once
Common Report Var(flag_inline_functions_called_once) Init(1) Optimization
Integrate functions called once into their callers

finline-limit-
Common RejectNegative Joined UInteger

finline-limit=
Common RejectNegative Joined UInteger
-finline-limit=<number>	Limit the size of inlined functions to <number>

finline-plan-
Common Joined RejectNegative
-finline-plan-<pass>=<file> Apply inlining decisions specified in <file> in inlining pass <pass>.

finstrument-functions
Common Report Var(flag_instrument_function_entry_exit)
Instrument function entry and exit with profiling calls

finstrument-functions-exclude-function-list=
Common RejectNegative Joined
-finstrument-functions-exclude-function-list=name,...  Do not instrument listed functions

finstrument-functions-exclude-file-list=
Common RejectNegative Joined
-finstrument-functions-exclude-file-list=filename,...  Do not instrument functions listed in files

fipa-cp
Common Report Var(flag_ipa_cp) Optimization
Perform Interprocedural constant propagation

fipa-cp-clone
Common Report Var(flag_ipa_cp_clone) Optimization
Perform cloning to make Interprocedural constant propagation stronger

fipa-pure-const
Common Report Var(flag_ipa_pure_const) Init(0) Optimization
Discover pure and const functions

fipa-pta
Common Report Var(flag_ipa_pta) Init(0) Optimization
Perform interprocedural points-to analysis

fipa-reference
Common Report Var(flag_ipa_reference) Init(0) Optimization
Discover readonly and non addressable static variables

fipa-type-escape
Common Report Var(flag_ipa_type_escape) Init(0) Optimization
Type based escape and alias analysis

fipa-matrix-reorg
Common Report Var(flag_ipa_matrix_reorg) Optimization
Perform matrix layout flattening and transposing based
on profiling information.

fipa-struct-reorg
Common Report Var(flag_ipa_struct_reorg)
Perform structure layout optimizations based
on profiling information.

fira-algorithm=
Common Joined RejectNegative
-fira-algorithm=[CB|priority] Set the used IRA algorithm

fira-region=
Common Joined RejectNegative
-fira-region=[one|all|mixed] Set regions for IRA

fira-coalesce
Common Report Var(flag_ira_coalesce) Init(0)
Do optimistic coalescing.

fira-share-save-slots
Common Report Var(flag_ira_share_save_slots) Init(1)
Share slots for saving different hard registers.

fira-share-spill-slots
Common Report Var(flag_ira_share_spill_slots) Init(1)
Share stack slots for spilled pseudo-registers.

fira-verbose=
Common RejectNegative Joined UInteger
-fira-verbose=<number> Control IRA's level of diagnostic messages.

fivopts
Common Report Var(flag_ivopts) Init(1) Optimization
Optimize induction variables on trees

fjump-tables
Common Var(flag_jump_tables) Init(1) Optimization
Use jump tables for sufficiently large switch statements

fkeep-inline-functions
Common Report Var(flag_keep_inline_functions)
Generate code for functions even if they are fully inlined

fkeep-static-consts
Common Report Var(flag_keep_static_consts) Init(1)
Emit static const variables even if they are not used

fleading-underscore
Common Report Var(flag_leading_underscore) Init(-1)
Give external symbols a leading underscore

floop-optimize
Common
Does nothing.  Preserved for backward compatibility.

fmath-errno
Common Report Var(flag_errno_math) Init(1) Optimization
Set errno after built-in math functions

fmem-report
Common Report Var(mem_report)
Report on permanent memory allocation

; This will attempt to merge constant section constants, if 1 only
; string constants and constants from constant pool, if 2 also constant
; variables.
fmerge-all-constants
Common Report Var(flag_merge_constants,2) Init(1) Optimization
Attempt to merge identical constants and constant variables

fmerge-constants
Common Report Var(flag_merge_constants,1) VarExists Optimization
Attempt to merge identical constants across compilation units

fmerge-debug-strings
Common Report Var(flag_merge_debug_strings) Init(1)
Attempt to merge identical debug strings across compilation units

fmessage-length=
Common RejectNegative Joined UInteger
-fmessage-length=<number>	Limit diagnostics to <number> characters per line.  0 suppresses line-wrapping

fmodulo-sched
Common Report Var(flag_modulo_sched) Optimization
Perform SMS based modulo scheduling before the first scheduling pass

fmodulo-sched-allow-regmoves
Common Report Var(flag_modulo_sched_allow_regmoves)
Perform SMS based modulo scheduling with register moves allowed

flimit-hot-components
Common Report Var(flag_limit_hot_components) Optimization Init(0)
Limit the size of hot components of the call graph to reduce I-cache pressure

fmove-loop-invariants
Common Report Var(flag_move_loop_invariants) Init(1) Optimization
Move loop invariant computations out of loops

fmudflap
Common RejectNegative Report Var(flag_mudflap)
Add mudflap bounds-checking instrumentation for single-threaded program

fmudflapth
Common RejectNegative Report VarExists Var(flag_mudflap,2)
Add mudflap bounds-checking instrumentation for multi-threaded program

fmudflapir
Common RejectNegative Report Var(flag_mudflap_ignore_reads)
Ignore read operations when inserting mudflap instrumentation

fdce
Common Var(flag_dce) Init(1) Optimization
Use the RTL dead code elimination pass

fdse
Common Var(flag_dse) Init(1) Optimization
Use the RTL dead store elimination pass

freschedule-modulo-scheduled-loops
Common Report Var(flag_resched_modulo_sched) Optimization
Enable/Disable the traditional scheduling in loops that already passed modulo scheduling

fnon-call-exceptions
Common Report Var(flag_non_call_exceptions) Optimization
Support synchronous non-call exceptions

fomit-frame-pointer
Common Report Var(flag_omit_frame_pointer) Optimization
When possible do not generate stack frames

foptimize-register-move
Common Report Var(flag_regmove) Optimization
Do the full register move optimization pass

foptimize-sibling-calls
Common Report Var(flag_optimize_sibling_calls) Optimization
Optimize sibling and tail recursive calls

fpre-ipa-mem-report
Common Report Var(pre_ipa_mem_report)
Report on memory allocation before interprocedural optimization

fpost-ipa-mem-report
Common Report Var(post_ipa_mem_report)
Report on memory allocation before interprocedural optimization

fpack-struct
Common Report Var(flag_pack_struct) Optimization
Pack structure members together without holes

fpack-struct=
Common RejectNegative Joined UInteger Optimization
-fpack-struct=<number>	Set initial maximum structure member alignment

fpcc-struct-return
Common Report Var(flag_pcc_struct_return,1) VarExists
Return small aggregates in memory, not registers

fpeel-loops
Common Report Var(flag_peel_loops) Optimization
Perform loop peeling

fpeephole
Common Report Var(flag_no_peephole,0) Optimization
Enable machine specific peephole optimizations

fpeephole2
Common Report Var(flag_peephole2) Optimization
Enable an RTL peephole pass before sched2

fpessimistic-inline-stack-limit
Common Report Var(flag_pessimistic_inline_stack_limit) Init(1) Optimization
Assume no stack reuse for locals when computing frame size during inlining

fPIC
Common Report Var(flag_pic,2)
Generate position-independent code if possible (large mode)

fPIE
Common Report Var(flag_pie,2)
Generate position-independent code for executables if possible (large mode)

fpic
Common Report Var(flag_pic,1) VarExists
Generate position-independent code if possible (small mode)

fpie
Common Report Var(flag_pie,1) VarExists
Generate position-independent code for executables if possible (small mode)

fplugin=
Common Joined RejectNegative
Specify a plugin to load

fplugin-arg-
Common Joined RejectNegative
-fplugin-arg-<name>-<key>[=<value>] Specify argument <key>=<value> for plugin <name>

fpredictive-commoning
Common Report Var(flag_predictive_commoning) Optimization
Run predictive commoning optimization.

fprefetch-loop-arrays
Common Report Var(flag_prefetch_loop_arrays) Optimization
Generate prefetch instructions, if available, for arrays in loops

fprofile
Common Report Var(profile_flag)
Enable basic program profiling code

fprofile-arcs
Common Report Var(profile_arc_flag)
Insert arc-based program profiling code

fprofile-correction
Common Report Var(flag_profile_correction)
Enable correction of flow inconsistent profile data input

fprofile-dir=
Common Joined RejectNegative
Set the top-level directory for storing the profile data.
The default is 'pwd'.

fprofile-dump
Common Report Var(flag_profile_dump) Init(0) Optimization
Dump CFG profile for comparison.

fprofile-generate
Common
Enable common options for generating profile info for profile feedback directed optimizations

fprofile-generate=
Common Joined RejectNegative
Enable common options for generating profile info for profile feedback directed optimizations, and set -fprofile-dir=

fprofile-use
Common Var(flag_profile_use)
Enable common options for performing profile feedback directed optimizations

fprofile-use=
Common Joined RejectNegative
Enable common options for performing profile feedback directed optimizations, and set -fprofile-dir=

fprofile-values
Common Report Var(flag_profile_values)
Insert code to profile values of expressions

frandom-seed
Common

frandom-seed=
Common Joined RejectNegative
-frandom-seed=<string>	Make compile reproducible using <string>

; This switch causes the command line that was used to create an
; object file to be recorded into the object file.  The exact format
; of this recording is target and binary file format dependent.
; It is related to the -fverbose-asm switch, but that switch only
; records information in the assembler output file as comments, so
; they never reach the object file.
frecord-gcc-switches
Common Report Var(flag_record_gcc_switches)
Record gcc command line switches in the object file.

freg-struct-return
Common Report Var(flag_pcc_struct_return,0) VarExists Optimization
Return small aggregates in registers

fregmove
Common Report Var(flag_regmove) Optimization
Enables a register move optimization

frename-registers
Common Report Var(flag_rename_registers) Init(2) Optimization
Perform a register renaming optimization pass

freorder-blocks
Common Report Var(flag_reorder_blocks) Optimization
Reorder basic blocks to improve code placement

freorder-blocks-and-partition
Common Report Var(flag_reorder_blocks_and_partition) Optimization
Reorder basic blocks and partition into hot and cold sections

freorder-functions
Common Report Var(flag_reorder_functions) Optimization
Reorder functions to improve code placement

frerun-cse-after-loop
Common Report Var(flag_rerun_cse_after_loop) Init(2) Optimization
Add a common subexpression elimination pass after loop optimizations

frerun-loop-opt
Common
Does nothing.  Preserved for backward compatibility.

frounding-math
Common Report Var(flag_rounding_math) Optimization
Disable optimizations that assume default FP rounding behavior

fsample-profile
Common Report Var(flag_sample_profile) Optimization
Use sample profile information for branch probabilities. The default sample
file is sp.data in 'pwd'.

fsample-profile=
Common Joined RejectNegative
Use sample profile information for branch probabilities. The sample
file is specified in the argument.

fsample-profile-aggregate-using=
Common Joined RejectNegative
-fsample-profile-aggregate-using=[avg|max] Use the maximum or average
number of samples across all instructions in a basic block as the
basic block weight

fsched-interblock
Common Report Var(flag_schedule_interblock) Init(1) Optimization
Enable scheduling across basic blocks

fsched-spec
Common Report Var(flag_schedule_speculative) Init(1) Optimization
Allow speculative motion of non-loads

fsched-spec-load
Common Report Var(flag_schedule_speculative_load) Optimization
Allow speculative motion of some loads

fsched-spec-load-dangerous
Common Report Var(flag_schedule_speculative_load_dangerous) Optimization
Allow speculative motion of more loads

fsched-verbose=
Common RejectNegative Joined
-fsched-verbose=<number>	Set the verbosity level of the scheduler

fsched2-use-superblocks
Common Report Var(flag_sched2_use_superblocks) Optimization
If scheduling post reload, do superblock scheduling

fsched2-use-traces
Common Report Var(flag_sched2_use_traces) Optimization
If scheduling post reload, do trace scheduling

fschedule-insns
Common Report Var(flag_schedule_insns) Optimization
Reschedule instructions before register allocation

fschedule-insns2
Common Report Var(flag_schedule_insns_after_reload) Optimization
Reschedule instructions after register allocation

; This flag should be on when a target implements non-trivial
; scheduling hooks, maybe saving some information for its own sake.
; On IA64, for example, this is used for correct bundling. 
fselective-scheduling
Common Report Var(flag_selective_scheduling) Optimization
Schedule instructions using selective scheduling algorithm

fselective-scheduling2
Common Report Var(flag_selective_scheduling2) Optimization 
Run selective scheduling after reload

fsel-sched-pipelining
Common Report Var(flag_sel_sched_pipelining) Init(0) Optimization
Perform software pipelining of inner loops during selective scheduling

fsel-sched-pipelining-outer-loops
Common Report Var(flag_sel_sched_pipelining_outer_loops) Init(0) Optimization
Perform software pipelining of outer loops during selective scheduling

fsel-sched-reschedule-pipelined
Common Report Var(flag_sel_sched_reschedule_pipelined) Init(0) Optimization
Reschedule pipelined regions without pipelining

; sched_stalled_insns means that insns can be moved prematurely from the queue
; of stalled insns into the ready list.
fsched-stalled-insns
Common Report Var(flag_sched_stalled_insns) Optimization UInteger
Allow premature scheduling of queued insns

fsched-stalled-insns=
Common RejectNegative Joined UInteger
-fsched-stalled-insns=<number>	Set number of queued insns that can be prematurely scheduled

; sched_stalled_insns_dep controls how many recently scheduled cycles will
; be examined for a dependency on a stalled insn that is candidate for
; premature removal from the queue of stalled insns into the ready list (has
; an effect only if the flag 'sched_stalled_insns' is set).
fsched-stalled-insns-dep
Common Report Var(flag_sched_stalled_insns_dep,1) Init(1) Optimization UInteger
Set dependence distance checking in premature scheduling of queued insns

fsched-stalled-insns-dep=
Common RejectNegative Joined UInteger
-fsched-stalled-insns-dep=<number>	Set dependence distance checking in premature scheduling of queued insns

fsection-anchors
Common Report Var(flag_section_anchors) Optimization
Access data in the same section from shared anchor points

fsee
Common Report Var(flag_see) Init(0)
Eliminate redundant sign extensions using LCM.

fzee
Common Report Var(flag_zee) Init(0)
Eliminate redundant zero extensions on targets that support implicit extensions.

fshow-column
Common C ObjC C++ ObjC++ Report Var(flag_show_column) Init(0)
Show column numbers in diagnostics, when available.  Default off

fsignaling-nans
Common Report Var(flag_signaling_nans) Optimization
Disable optimizations observable by IEEE signaling NaNs

fsigned-zeros
Common Report Var(flag_signed_zeros) Init(1) Optimization
Disable floating point optimizations that ignore the IEEE signedness of zero

fsingle-precision-constant
Common Report Var(flag_single_precision_constant) Optimization
Convert floating point constants to single precision constants

fsplit-ivs-in-unroller
Common Report Var(flag_split_ivs_in_unroller) Init(1) Optimization
Split lifetimes of induction variables when loops are unrolled

fsplit-wide-types
Common Report Var(flag_split_wide_types) Optimization
Split wide types into independent registers

fvariable-expansion-in-unroller
Common Report Var(flag_variable_expansion_in_unroller) Optimization
Apply variable expansion when loops are unrolled

fstack-check=
Common Report RejectNegative Joined
-fstack-check=[no|generic|specific]	Insert stack checking code into the program

fstack-check
Common Report
Insert stack checking code into the program.  Same as -fstack-check=specific

fstack-limit
Common

fstack-limit-register=
Common RejectNegative Joined
-fstack-limit-register=<register>	Trap if the stack goes past <register>

fstack-limit-symbol=
Common RejectNegative Joined
-fstack-limit-symbol=<name>	Trap if the stack goes past symbol <name>

fstack-protector
Common Report Var(flag_stack_protect, 1)
Use propolice as a stack protection method

fstack-protector-all
Common Report RejectNegative Var(flag_stack_protect, 2) VarExists
Use a stack protection method for every function

fstrength-reduce
Common
Does nothing.  Preserved for backward compatibility.

; Nonzero if we should do (language-dependent) alias analysis.
; Typically, this analysis will assume that expressions of certain
; types do not alias expressions of certain other types.  Only used
; if alias analysis (in general) is enabled.
fstrict-aliasing
Common Report Var(flag_strict_aliasing) Optimization
Assume strict aliasing rules apply

fstrict-overflow
Common Report Var(flag_strict_overflow)
Treat signed overflow as undefined

fsyntax-only
Common Report Var(flag_syntax_only)
Check for syntax errors, then stop

ftest-coverage
Common Report Var(flag_test_coverage)
Create data files needed by \"gcov\"

fthread-jumps
Common Report Var(flag_thread_jumps) Optimization
Perform jump threading optimizations

ftime-report
Common Report Var(time_report)
Report the time taken by each compiler pass

ftls-model=
Common Joined RejectNegative
-ftls-model=[global-dynamic|local-dynamic|initial-exec|local-exec]	Set the default thread-local storage code generation model

ftoplevel-reorder
Common Report Var(flag_toplevel_reorder) Init(2) Optimization
Reorder top level functions, variables, and asms

ftracer
Common Report Var(flag_tracer)
Perform superblock formation via tail duplication

; Zero means that floating-point math operations cannot generate a
; (user-visible) trap.  This is the case, for example, in nonstop
; IEEE 754 arithmetic.
ftrapping-math
Common Report Var(flag_trapping_math) Init(1) Optimization
Assume floating-point operations can trap

ftrapv
Common Report Var(flag_trapv) Optimization
Trap for signed overflow in addition, subtraction and multiplication

ftree-ccp
Common Report Var(flag_tree_ccp) Optimization
Enable SSA-CCP optimization on trees

ftree-store-ccp
Common
Does nothing.  Preserved for backward compatibility.

ftree-ch
Common Report Var(flag_tree_ch) Optimization
Enable loop header copying on trees

ftree-copyrename
Common Report Var(flag_tree_copyrename) Optimization
Replace SSA temporaries with better names in copies

ftree-copy-prop
Common Report Var(flag_tree_copy_prop) Optimization
Enable copy propagation on trees

ftree-store-copy-prop
Common
Does nothing.  Preserved for backward compatibility.

ftree-cselim
Common Report Var(flag_tree_cselim) Init(2) Optimization
Transform condition stores into unconditional ones

ftree-switch-conversion
Common Report Var(flag_tree_switch_conversion) Optimization
Perform conversions of switch initializations.

ftree-dce
Common Report Var(flag_tree_dce) Optimization
Enable SSA dead code elimination optimization on trees

ftree-dominator-opts
Common Report Var(flag_tree_dom) Optimization
Enable dominator optimizations

ftree-dse
Common Report Var(flag_tree_dse) Optimization
Enable dead store elimination

ftree-fre
Common Report Var(flag_tree_fre) Optimization
Enable Full Redundancy Elimination (FRE) on trees

ftree-lr-shrinking
Common Report Var(flag_tree_lr_shrinking) Optimization
Enable Live Range Shrinking optimization


ftree-loop-distribution
Common Report Var(flag_tree_loop_distribution) Optimization
Enable loop distribution on trees

ftree-loop-im
Common Report Var(flag_tree_loop_im) Init(1) Optimization
Enable loop invariant motion on trees

ftree-loop-linear
Common Report Var(flag_tree_loop_linear) Optimization
Enable linear loop transforms on trees

ftree-loop-ivcanon
Common Report Var(flag_tree_loop_ivcanon) Init(1) Optimization
Create canonical induction variables in loops

ftree-loop-optimize
Common Report Var(flag_tree_loop_optimize) Init(1) Optimization
Enable loop optimizations on tree level

ftree-parallelize-loops=
Common Report Joined UInteger Var(flag_tree_parallelize_loops) Init(1)
Enable automatic parallelization of loops

ftree-pre
Common Report Var(flag_tree_pre) Optimization
Enable SSA-PRE optimization on trees

ftree-reassoc
Common Report Var(flag_tree_reassoc) Init(1) Optimization
Enable reassociation on tree level

ftree-salias
Common
Does nothing.  Preserved for backward compatibility.

ftree-sink
Common Report Var(flag_tree_sink) Optimization
Enable SSA code sinking on trees

ftree-sra
Common Report Var(flag_tree_sra) Optimization
Perform scalar replacement of aggregates

ftree-ter
Common Report Var(flag_tree_ter) Init(1) Optimization
Replace temporary expressions in the SSA->normal pass

ftree-lrs
Common Report Var(flag_tree_live_range_split) Optimization
Perform live range splitting during the SSA->normal pass

ftree-vrp
Common Report Var(flag_tree_vrp) Init(0) Optimization
Perform Value Range Propagation on trees

fstrict-enum-precision
Common Report Var(flag_strict_enum_precision) Init(1) Optimization
Perform transformations based on enum precision

funit-at-a-time
Common Report Var(flag_unit_at_a_time) Init(1) Optimization
Compile whole compilation unit at a time

funroll-loops
Common Report Var(flag_unroll_loops) Optimization
Perform loop unrolling when iteration count is known

funroll-all-loops
Common Report Var(flag_unroll_all_loops) Optimization
Perform loop unrolling for all loops

; Nonzero means that loop optimizer may assume that the induction variables
; that control loops do not overflow and that the loops with nontrivial
; exit condition are not infinite
funsafe-loop-optimizations
Common Report Var(flag_unsafe_loop_optimizations) Optimization
Allow loop optimizations to assume that the loops behave in normal way

fassociative-math
Common Report Var(flag_associative_math)
Allow optimization for floating-point arithmetic which may change the
result of the operation due to rounding.

freciprocal-math
Common Report Var(flag_reciprocal_math)
Same as -fassociative-math for expressions which include division.

; Nonzero means that unsafe floating-point math optimizations are allowed
; for the sake of speed.  IEEE compliance is not guaranteed, and operations
; are allowed to assume that their arguments and results are "normal"
; (e.g., nonnegative for SQRT).
funsafe-math-optimizations
Common Report Var(flag_unsafe_math_optimizations) Optimization
Allow math optimizations that may violate IEEE or ISO standards

funswitch-loops
Common Report Var(flag_unswitch_loops) Optimization
Perform loop unswitching

funwind-tables
Common Report Var(flag_unwind_tables) Optimization
Just generate unwind tables for exception handling

fvar-tracking
Common Report Var(flag_var_tracking) VarExists Optimization
Perform variable tracking

fvar-tracking-uninit
Common Report Var(flag_var_tracking_uninit) Optimization
Perform variable tracking and also tag variables that are uninitialized

ftree-vectorize
Common Report Var(flag_tree_vectorize) Optimization
Enable loop vectorization on trees

fvect-cost-model
Common Report Var(flag_vect_cost_model) Optimization
Enable use of cost model in vectorization

ftree-vect-loop-version
Common Report Var(flag_tree_vect_loop_version) Init(1) Optimization
Enable loop versioning when doing loop vectorization on trees

ftree-vectorizer-verbose=
Common RejectNegative Joined
-ftree-vectorizer-verbose=<number>	Set the verbosity level of the vectorizer

ftree-scev-cprop
Common Report Var(flag_tree_scev_cprop) Init(1) Optimization
Enable copy propagation of scalar-evolution information.

; -fverbose-asm causes extra commentary information to be produced in
; the generated assembly code (to make it more readable).  This option
; is generally only of use to those who actually need to read the
; generated assembly code (perhaps while debugging the compiler itself).
; -fno-verbose-asm, the default, causes the extra information
; to not be added and is useful when comparing two assembler files.
fverbose-asm
Common Report Var(flag_verbose_asm)
Add extra commentary to assembler output

fvisibility=
Common Joined RejectNegative
-fvisibility=[default|internal|hidden|protected]	Set the default symbol visibility


fvpt
Common Report Var(flag_value_profile_transformations) Optimization
Use expression value profiles in optimizations

fweb
Common Report Var(flag_web) Init(2) Optimization
Construct webs and split unrelated uses of single variable

ftree-builtin-call-dce
Common Report Var(flag_tree_builtin_call_dce) Init(0) Optimization
Enable conditional dead code elimination for builtin calls

fwhole-program
Common Report Var(flag_whole_program) Init(0) Optimization
Perform whole program optimizations

fwrapv
Common Report Var(flag_wrapv) Optimization
Assume signed arithmetic overflow wraps around

fzero-initialized-in-bss
Common Report Var(flag_zero_initialized_in_bss) Init(1)
Put zero initialized data in the bss section

g
Common JoinedOrMissing
Generate debug information in default format

gcoff
Common JoinedOrMissing Negative(gdwarf-2)
Generate debug information in COFF format

gdwarf-2
Common JoinedOrMissing Negative(gdwarf-4)
Generate debug information in DWARF v2 format

gdwarf-4
Common JoinedOrMissing Negative(gstabs)
Generate debug information in DWARF v4 format (experimental)

ggdb
Common JoinedOrMissing
Generate debug information in default extended format

gmlt
Common RejectNegative
Generate debug information at level 1 with minimal line table

gstabs
Common JoinedOrMissing Negative(gstabs+)
Generate debug information in STABS format

gstabs+
Common JoinedOrMissing Negative(gvms)
Generate debug information in extended STABS format

gvms
Common JoinedOrMissing Negative(gxcoff)
Generate debug information in VMS format

gxcoff
Common JoinedOrMissing Negative(gxcoff+)
Generate debug information in XCOFF format

gxcoff+
Common JoinedOrMissing Negative(gcoff)
Generate debug information in extended XCOFF format

o
Common Joined Separate
-o <file>	Place output into <file>

p
Common Var(profile_flag)
Enable function profiling

pedantic
Common Var(pedantic)
Issue warnings needed for strict compliance to the standard

pedantic-errors
Common
Like -pedantic but issue them as errors

quiet
Common Var(quiet_flag)
Do not display functions compiled or elapsed time

version
Common Var(version_flag)
Display the compiler's version

w
Common Var(inhibit_warnings)
Suppress warnings

shared
Common RejectNegative Negative(pie)
Create a shared library

pie
Common RejectNegative Negative(shared)
Create a position independent executable

; This comment is to ensure we retain the blank line above.