1..
2  -------------------------------------------------------------------
3  NOTE: This file is automatically generated by running clang-tblgen
4  -gen-opt-docs. Do not edit this file by hand!!
5  -------------------------------------------------------------------
6
7=====================================
8Clang command line argument reference
9=====================================
10.. contents::
11   :local:
12
13Introduction
14============
15
16This page lists the command line arguments currently supported by the
17GCC-compatible ``clang`` and ``clang++`` drivers.
18
19
20.. program:: clang
21.. option:: -B<prefix>, --prefix <arg>, --prefix=<arg>
22
23Search $prefix$file for executables, libraries, and data files. If $prefix is a directory, search $prefix/$file
24
25.. option:: -F<arg>
26
27Add directory to framework include search path
28
29.. option:: -ObjC
30
31Treat source input files as Objective-C inputs
32
33.. program:: clang1
34.. option:: -ObjC++
35.. program:: clang
36
37Treat source input files as Objective-C++ inputs
38
39.. option:: -Qn, -fno-ident
40
41Do not emit metadata containing compiler name and version
42
43.. option:: -Qunused-arguments
44
45Don't emit warning for unused driver arguments
46
47.. option:: -Qy, -fident
48
49Emit metadata containing compiler name and version
50
51.. option:: -Wa,<arg>,<arg2>...
52
53Pass the comma separated arguments in <arg> to the assembler
54
55.. option:: -Wlarge-by-value-copy=<arg>
56
57.. option:: -Xarch\_<arg1> <arg2>
58
59.. program:: clang1
60.. option:: -Xarch\_device <arg>
61.. program:: clang
62
63Pass <arg> to the CUDA/HIP device compilation
64
65.. program:: clang2
66.. option:: -Xarch\_host <arg>
67.. program:: clang
68
69Pass <arg> to the CUDA/HIP host compilation
70
71.. option:: -Xcuda-fatbinary <arg>
72
73Pass <arg> to fatbinary invocation
74
75.. option:: -Xcuda-ptxas <arg>
76
77Pass <arg> to the ptxas assembler
78
79.. option:: -Z<arg>
80
81.. option:: -a<arg>, --profile-blocks
82
83.. option:: -all\_load
84
85.. option:: -allowable\_client <arg>
86
87.. option:: --analyze
88
89Run the static analyzer
90
91.. option:: --analyzer-no-default-checks
92
93.. option:: --analyzer-output<arg>
94
95Static analyzer report output format (html\|plist\|plist-multi-file\|plist-html\|sarif\|sarif-html\|text).
96
97.. option:: -arch <arg>
98
99.. program:: clang1
100.. option:: -arch\_errors\_fatal
101.. program:: clang
102
103.. program:: clang2
104.. option:: -arch\_only <arg>
105.. program:: clang
106
107.. option:: -arcmt-migrate-emit-errors
108
109Emit ARC errors even if the migrator can fix them
110
111.. option:: -arcmt-migrate-report-output <arg>
112
113Output path for the plist report
114
115.. option:: --autocomplete=<arg>
116
117.. option:: -bind\_at\_load
118
119.. option:: -bundle
120
121.. program:: clang1
122.. option:: -bundle\_loader <arg>
123.. program:: clang
124
125.. option:: -client\_name<arg>
126
127.. option:: -compatibility\_version<arg>
128
129.. option:: --config <arg>
130
131Specifies configuration file
132
133.. option:: --constant-cfstrings
134
135.. option:: --cuda-feature=<arg>
136
137Manually specify the CUDA feature to use
138
139.. option:: --cuda-include-ptx=<arg>, --no-cuda-include-ptx=<arg>
140
141Include PTX for the following GPU architecture (e.g. sm\_35) or 'all'. May be specified more than once.
142
143.. option:: --cuda-noopt-device-debug, --no-cuda-noopt-device-debug
144
145Enable device-side debug info generation. Disables ptxas optimizations.
146
147.. option:: -cuid=<arg>
148
149An ID for compilation unit, which should be the same for the same compilation unit but different for different compilation units. It is used to externalize device-side static variables for single source offloading languages CUDA and HIP so that they can be accessed by the host code of the same compilation unit.
150
151.. option:: -current\_version<arg>
152
153.. option:: -darwin-target-variant <arg>
154
155Generate code for an additional runtime variant of the deployment target
156
157.. option:: -darwin-target-variant-triple <arg>
158
159Specify the darwin target variant triple
160
161.. option:: -dead\_strip
162
163.. option:: -dependency-dot <arg>
164
165Filename to write DOT-formatted header dependencies to
166
167.. option:: -dependency-file <arg>
168
169Filename (or -) to write dependency output to
170
171.. option:: -dsym-dir<dir>
172
173Directory to output dSYM's (if any) to
174
175.. option:: -dumpmachine
176
177.. option:: -dumpversion
178
179.. option:: --dyld-prefix=<arg>, --dyld-prefix <arg>
180
181.. option:: -dylib\_file <arg>
182
183.. option:: -dylinker
184
185.. program:: clang1
186.. option:: -dylinker\_install\_name<arg>
187.. program:: clang
188
189.. option:: -dynamic
190
191.. option:: -dynamiclib
192
193.. option:: -emit-ast
194
195Emit Clang AST files for source inputs
196
197.. option:: --emit-static-lib
198
199Enable linker job to emit a static library.
200
201.. option:: -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
202
203Trivial automatic variable initialization to zero is only here for benchmarks, it'll eventually be removed, and I'm OK with that because I'm only using it to benchmark
204
205.. option:: --end-no-unused-arguments
206
207Start emitting warnings for unused driver arguments
208
209.. option:: -exported\_symbols\_list <arg>
210
211.. option:: -faligned-new=<arg>
212
213.. option:: -fautomatic
214
215.. option:: -ffixed-r19
216
217Reserve register r19 (Hexagon only)
218
219.. option:: -fgpu-default-stream=<arg>
220
221Specify default stream. The default value is 'legacy'. (HIP only). <arg> must be 'legacy' or 'per-thread'.
222
223.. option:: -fgpu-flush-denormals-to-zero, -fcuda-flush-denormals-to-zero, -fno-gpu-flush-denormals-to-zero
224
225Flush denormal floating point values to zero in CUDA/HIP device mode.
226
227.. option:: -fheinous-gnu-extensions
228
229.. option:: -flat\_namespace
230
231.. option:: -fopenmp-targets=<arg1>,<arg2>...
232
233Specify comma-separated list of triples OpenMP offloading targets to be supported
234
235.. option:: -force\_cpusubtype\_ALL
236
237.. program:: clang1
238.. option:: -force\_flat\_namespace
239.. program:: clang
240
241.. program:: clang2
242.. option:: -force\_load <arg>
243.. program:: clang
244
245.. option:: -fplugin-arg-<name>-<arg>
246
247Pass <arg> to plugin <name>
248
249.. option:: -framework <arg>
250
251.. option:: -frtlib-add-rpath, -fno-rtlib-add-rpath
252
253Add -rpath with architecture-specific resource directory to the linker flags
254
255.. option:: -fsanitize-system-ignorelist=<arg>, -fsanitize-system-blacklist=<arg>
256
257Path to system ignorelist file for sanitizers
258
259.. option:: -fshow-skipped-includes
260
261#include files may be "skipped" due to include guard optimization
262             or #pragma once. This flag makes -H show also such includes.
263
264.. option:: -fsystem-module
265
266Build this module as a system module. Only used with -emit-module
267
268.. option:: -fuse-cuid=<arg>
269
270Method to generate ID's for compilation units for single source offloading languages CUDA and HIP: 'hash' (ID's generated by hashing file path and command line options) \| 'random' (ID's generated as random numbers) \| 'none' (disabled). Default is 'hash'. This option will be overridden by option '-cuid=\[ID\]' if it is specified.
271
272.. option:: --gcc-toolchain=<arg>
273
274Search for GCC installation in the specified directory on targets which commonly use GCC. The directory usually contains 'lib{,32,64}/gcc{,-cross}/$triple' and 'include'. If specified, sysroot is skipped for GCC detection. Note: executables (e.g. ld) used by the compiler are not overridden by the selected GCC installation
275
276.. option:: -gcodeview
277
278Generate CodeView debug information
279
280.. option:: -gcodeview-ghash, -gno-codeview-ghash
281
282Emit type record hashes in a .debug$H section
283
284.. option:: -gen-reproducer=<arg>, -fno-crash-diagnostics (equivalent to -gen-reproducer=off)
285
286Emit reproducer on (option: off, crash (default), error, always)
287
288.. option:: --gpu-instrument-lib=<arg>
289
290Instrument device library for HIP, which is a LLVM bitcode containing \_\_cyg\_profile\_func\_enter and \_\_cyg\_profile\_func\_exit
291
292.. option:: --gpu-max-threads-per-block=<arg>
293
294Default max threads per block for kernel launch bounds for HIP
295
296.. option:: -headerpad\_max\_install\_names<arg>
297
298.. option:: -help, --help, /help<arg>, -help<arg>, --help<arg>
299
300Display available options
301
302.. option:: --help-hidden
303
304Display help for hidden options
305
306.. option:: --hip-link
307
308Link clang-offload-bundler bundles for HIP
309
310.. option:: --hip-version=<arg>
311
312HIP version in the format of major.minor.patch
313
314.. option:: -ibuiltininc
315
316Enable builtin #include directories even when -nostdinc is used before or after -ibuiltininc. Using -nobuiltininc after the option disables it
317
318.. option:: -image\_base <arg>
319
320.. option:: -index-header-map
321
322Make the next included directory (-I or -F) an indexer header map
323
324.. option:: -init <arg>
325
326.. option:: -install\_name <arg>
327
328.. option:: -interface-stub-version=<arg>
329
330.. option:: -keep\_private\_externs
331
332.. option:: -lazy\_framework <arg>
333
334.. program:: clang1
335.. option:: -lazy\_library <arg>
336.. program:: clang
337
338.. option:: -mbig-endian, -EB
339
340.. option:: -menable-unsafe-fp-math
341
342Allow unsafe floating-point math optimizations which may decrease precision
343
344.. option:: -mharden-sls=<arg>
345
346Select straight-line speculation hardening scope (ARM/AArch64/X86 only). <arg> must be: all, none, retbr(ARM/AArch64), blr(ARM/AArch64), comdat(ARM/AArch64), nocomdat(ARM/AArch64), return(X86), indirect-jmp(X86)
347
348.. option:: --migrate
349
350Run the migrator
351
352.. option:: -mios-simulator-version-min=<arg>, -miphonesimulator-version-min=<arg>
353
354.. option:: -mlinker-version=<arg>
355
356.. option:: -mlittle-endian, -EL
357
358.. option:: -mllvm <arg>
359
360Additional arguments to forward to LLVM's option processing
361
362.. option:: -mmlir <arg>
363
364Additional arguments to forward to MLIR's option processing
365
366.. option:: -module-dependency-dir <arg>
367
368Directory to dump module dependencies to
369
370.. option:: -mtvos-simulator-version-min=<arg>, -mappletvsimulator-version-min=<arg>
371
372.. option:: -multi\_module
373
374.. option:: -multiply\_defined <arg>
375
376.. program:: clang1
377.. option:: -multiply\_defined\_unused <arg>
378.. program:: clang
379
380.. option:: -mwatchos-simulator-version-min=<arg>, -mwatchsimulator-version-min=<arg>
381
382.. option:: --no-cuda-version-check
383
384Don't error out if the detected version of the CUDA install is too low for the requested CUDA gpu architecture.
385
386.. option:: -no-hip-rt
387
388Do not link against HIP runtime libraries
389
390.. option:: -no-integrated-cpp, --no-integrated-cpp
391
392.. option:: -no\_dead\_strip\_inits\_and\_terms
393
394.. option:: -nobuiltininc
395
396Disable builtin #include directories
397
398.. option:: -nodefaultlibs
399
400.. option:: -nodriverkitlib
401
402.. option:: -nofixprebinding
403
404.. option:: -nogpuinc, -nocudainc
405
406Do not add include paths for CUDA/HIP and do not include the default CUDA/HIP wrapper headers
407
408.. option:: -nogpulib, -nocudalib
409
410Do not link device library for CUDA/HIP device compilation
411
412.. option:: -nohipwrapperinc
413
414Do not include the default HIP wrapper headers and include paths
415
416.. option:: -nolibc
417
418.. option:: -nomultidefs
419
420.. option:: -nopie, -no-pie
421
422.. option:: -noprebind
423
424.. option:: -noprofilelib
425
426.. option:: -noseglinkedit
427
428.. option:: -nostdinc, --no-standard-includes
429
430.. program:: clang1
431.. option:: -nostdinc++
432.. program:: clang
433
434Disable standard #include directories for the C++ standard library
435
436.. option:: -nostdlib++
437
438.. option:: -nostdlibinc
439
440.. program:: clang1
441.. option:: -o<file>, /Fo<arg>, -Fo<arg>, --output <arg>, --output=<arg>
442.. program:: clang
443
444Write output to <file>
445
446.. option:: -objcmt-allowlist-dir-path=<arg>, -objcmt-white-list-dir-path=<arg>, -objcmt-whitelist-dir-path=<arg>
447
448Only modify files with a filename contained in the provided directory path
449
450.. option:: -objcmt-atomic-property
451
452Make migration to 'atomic' properties
453
454.. option:: -objcmt-migrate-all
455
456Enable migration to modern ObjC
457
458.. option:: -objcmt-migrate-annotation
459
460Enable migration to property and method annotations
461
462.. option:: -objcmt-migrate-designated-init
463
464Enable migration to infer NS\_DESIGNATED\_INITIALIZER for initializer methods
465
466.. option:: -objcmt-migrate-instancetype
467
468Enable migration to infer instancetype for method result type
469
470.. option:: -objcmt-migrate-literals
471
472Enable migration to modern ObjC literals
473
474.. option:: -objcmt-migrate-ns-macros
475
476Enable migration to NS\_ENUM/NS\_OPTIONS macros
477
478.. option:: -objcmt-migrate-property
479
480Enable migration to modern ObjC property
481
482.. option:: -objcmt-migrate-property-dot-syntax
483
484Enable migration of setter/getter messages to property-dot syntax
485
486.. option:: -objcmt-migrate-protocol-conformance
487
488Enable migration to add protocol conformance on classes
489
490.. option:: -objcmt-migrate-readonly-property
491
492Enable migration to modern ObjC readonly property
493
494.. option:: -objcmt-migrate-readwrite-property
495
496Enable migration to modern ObjC readwrite property
497
498.. option:: -objcmt-migrate-subscripting
499
500Enable migration to modern ObjC subscripting
501
502.. option:: -objcmt-ns-nonatomic-iosonly
503
504Enable migration to use NS\_NONATOMIC\_IOSONLY macro for setting property's 'atomic' attribute
505
506.. option:: -objcmt-returns-innerpointer-property
507
508Enable migration to annotate property with NS\_RETURNS\_INNER\_POINTER
509
510.. option:: -object
511
512.. option:: -object-file-name=<file>, -object-file-name <arg>
513
514Set the output <file> for debug infos
515
516.. option:: --offload-arch=<arg>, --cuda-gpu-arch=<arg>, --no-offload-arch=<arg>
517
518CUDA offloading device architecture (e.g. sm\_35), or HIP offloading target ID in the form of a device architecture followed by target ID features delimited by a colon. Each target ID feature is a pre-defined string followed by a plus or minus sign (e.g. gfx908:xnack+:sramecc-).  May be specified more than once.
519
520.. option:: --offload-device-only, --cuda-device-only
521
522Only compile for the offloading device.
523
524.. option:: --offload-host-device, --cuda-compile-host-device
525
526Only compile for the offloading host.
527
528.. option:: --offload-host-only, --cuda-host-only
529
530Only compile for the offloading host.
531
532.. option:: --offload=<arg1>,<arg2>...
533
534Specify comma-separated list of offloading target triples (CUDA and HIP only)
535
536.. option:: -p, --profile
537
538.. option:: -pagezero\_size<arg>
539
540.. option:: -pg
541
542Enable mcount instrumentation
543
544.. option:: -pipe, --pipe
545
546Use pipes between commands, when possible
547
548.. option:: -prebind
549
550.. program:: clang1
551.. option:: -prebind\_all\_twolevel\_modules
552.. program:: clang
553
554.. option:: -preload
555
556.. option:: --print-diagnostic-categories
557
558.. option:: -print-diagnostic-options, --print-diagnostic-options
559
560Print all of Clang's warning options
561
562.. option:: -print-effective-triple, --print-effective-triple
563
564Print the effective target triple
565
566.. option:: -print-file-name=<file>, --print-file-name=<file>, --print-file-name <arg>
567
568Print the full library path of <file>
569
570.. option:: -print-ivar-layout
571
572Enable Objective-C Ivar layout bitmap print trace
573
574.. option:: -print-libgcc-file-name, --print-libgcc-file-name
575
576Print the library path for the currently used compiler runtime library ("libgcc.a" or "libclang\_rt.builtins.\*.a")
577
578.. option:: -print-multi-directory, --print-multi-directory
579
580.. option:: -print-multi-lib, --print-multi-lib
581
582.. option:: -print-multiarch, --print-multiarch
583
584Print the multiarch target triple
585
586.. option:: -print-prog-name=<name>, --print-prog-name=<name>, --print-prog-name <arg>
587
588Print the full program path of <name>
589
590.. option:: -print-resource-dir, --print-resource-dir
591
592Print the resource directory pathname
593
594.. option:: -print-rocm-search-dirs, --print-rocm-search-dirs
595
596Print the paths used for finding ROCm installation
597
598.. option:: -print-runtime-dir, --print-runtime-dir
599
600Print the directory pathname containing clangs runtime libraries
601
602.. option:: -print-search-dirs, --print-search-dirs
603
604Print the paths used for finding libraries and programs
605
606.. option:: -print-target-triple, --print-target-triple
607
608Print the normalized target triple
609
610.. option:: -print-targets, --print-targets
611
612Print the registered targets
613
614.. option:: -private\_bundle
615
616.. option:: --product-name=<arg>
617
618.. option:: -pthread, -no-pthread
619
620Support POSIX threads in generated code
621
622.. option:: -pthreads
623
624.. option:: -read\_only\_relocs <arg>
625
626.. option:: -relocatable-pch, --relocatable-pch
627
628Whether to build a relocatable precompiled header
629
630.. option:: -remap
631
632.. option:: -rewrite-legacy-objc
633
634Rewrite Legacy Objective-C source to C++
635
636.. option:: -rtlib=<arg>, --rtlib=<arg>, --rtlib <arg>
637
638Compiler runtime library to use
639
640.. option:: -save-stats=<arg>, --save-stats=<arg>, -save-stats (equivalent to -save-stats=cwd), --save-stats (equivalent to -save-stats=cwd)
641
642Save llvm statistics.
643
644.. option:: -save-temps=<arg>, --save-temps=<arg>, -save-temps (equivalent to -save-temps=cwd), --save-temps (equivalent to -save-temps=cwd)
645
646Save intermediate compilation results.
647
648.. option:: -sectalign <arg1> <arg2> <arg3>
649
650.. option:: -sectcreate <arg1> <arg2> <arg3>
651
652.. option:: -sectobjectsymbols <arg1> <arg2>
653
654.. option:: -sectorder <arg1> <arg2> <arg3>
655
656.. option:: -seg1addr<arg>
657
658.. option:: -seg\_addr\_table <arg>
659
660.. program:: clang1
661.. option:: -seg\_addr\_table\_filename <arg>
662.. program:: clang
663
664.. option:: -segaddr <arg1> <arg2>
665
666.. option:: -segcreate <arg1> <arg2> <arg3>
667
668.. option:: -seglinkedit
669
670.. option:: -segprot <arg1> <arg2> <arg3>
671
672.. option:: -segs\_read\_<arg>
673
674.. program:: clang1
675.. option:: -segs\_read\_only\_addr <arg>
676.. program:: clang
677
678.. program:: clang2
679.. option:: -segs\_read\_write\_addr <arg>
680.. program:: clang
681
682.. option:: -serialize-diagnostics <arg>, --serialize-diagnostics <arg>
683
684Serialize compiler diagnostics to a file
685
686.. option:: -shared-libgcc
687
688.. option:: -shared-libsan, -shared-libasan
689
690Dynamically link the sanitizer runtime
691
692.. option:: -single\_module
693
694.. option:: --start-no-unused-arguments
695
696Don't emit warnings about unused arguments for the following arguments
697
698.. option:: -static-libgcc
699
700.. option:: -static-libsan
701
702Statically link the sanitizer runtime
703
704.. option:: -static-libstdc++
705
706.. option:: -static-openmp
707
708Use the static host OpenMP runtime while linking.
709
710.. option:: -std-default=<arg>
711
712.. option:: -stdlib=<arg>, --stdlib=<arg>, --stdlib <arg>
713
714C++ standard library to use. <arg> must be 'libc++', 'libstdc++' or 'platform'.
715
716.. option:: -sub\_library<arg>
717
718.. program:: clang1
719.. option:: -sub\_umbrella<arg>
720.. program:: clang
721
722.. option:: --sysroot=<arg>, --sysroot <arg>
723
724.. option:: --target-help
725
726.. option:: --target=<arg>, -target <arg>
727
728Generate code for the given target
729
730.. option:: -time
731
732Time individual commands
733
734.. option:: -traditional, --traditional
735
736.. option:: -traditional-cpp, --traditional-cpp
737
738Enable some traditional CPP emulation
739
740.. option:: -twolevel\_namespace
741
742.. program:: clang1
743.. option:: -twolevel\_namespace\_hints
744.. program:: clang
745
746.. option:: -umbrella <arg>
747
748.. option:: -unexported\_symbols\_list <arg>
749
750.. option:: -unwindlib=<arg>, --unwindlib=<arg>
751
752Unwind library to use. <arg> must be 'libgcc', 'unwindlib' or 'platform'.
753
754.. option:: -v, --verbose
755
756Show commands to run and use verbose output
757
758.. option:: --verify-debug-info
759
760Verify the binary representation of debug output
761
762.. option:: --version
763
764Print version information
765
766.. option:: -w, --no-warnings
767
768Suppress all warnings
769
770.. option:: -weak-l<arg>
771
772.. option:: -weak\_framework <arg>
773
774.. program:: clang1
775.. option:: -weak\_library <arg>
776.. program:: clang
777
778.. program:: clang2
779.. option:: -weak\_reference\_mismatches <arg>
780.. program:: clang
781
782.. option:: -whatsloaded
783
784.. option:: -why\_load, -whyload
785
786.. option:: -working-directory<arg>, -working-directory=<arg>
787
788Resolve file paths relative to the specified directory
789
790.. option:: -x<language>, --language <arg>, --language=<arg>
791
792Treat subsequent input files as having type <language>
793
794.. option:: -y<arg>
795
796Actions
797=======
798The action to perform on the input.
799
800.. option:: -E, --preprocess
801
802Only run the preprocessor
803
804.. option:: -S, --assemble
805
806Only run preprocess and compilation steps
807
808.. option:: -c, --compile
809
810Only run preprocess, compile, and assemble steps
811
812.. option:: -emit-interface-stubs
813
814Generate Interface Stub Files.
815
816.. option:: -emit-llvm
817
818Use the LLVM representation for assembler and object files
819
820.. option:: -emit-merged-ifs
821
822Generate Interface Stub Files, emit merged text not binary.
823
824.. option:: -extract-api
825
826Extract API information
827
828.. option:: -fdriver-only
829
830Only run the driver.
831
832.. option:: -fsyntax-only
833
834.. option:: -module-file-info
835
836Provide information about a particular module file
837
838.. option:: --precompile
839
840Only precompile the input
841
842.. option:: -rewrite-objc
843
844Rewrite Objective-C source to C++
845
846.. option:: -verify-pch
847
848Load and verify that a pre-compiled header file is not stale
849
850Compilation flags
851=================
852
853Flags controlling the behavior of Clang during compilation. These flags have
854no effect during actions that do not perform compilation.
855
856.. option:: -Xassembler <arg>
857
858Pass <arg> to the assembler
859
860.. option:: -Xclang <arg>
861
862Pass <arg> to the clang compiler
863
864.. option:: -Xopenmp-target <arg>
865
866Pass <arg> to the target offloading toolchain.
867
868.. program:: clang1
869.. option:: -Xopenmp-target=<triple> <arg>
870.. program:: clang
871
872Pass <arg> to the target offloading toolchain identified by <triple>.
873
874.. option:: -ansi, --ansi
875
876.. option:: -fc++-abi=<arg>
877
878C++ ABI to use. This will override the target C++ ABI.
879
880.. option:: -fclang-abi-compat=<version>
881
882Attempt to match the ABI of Clang <version>. <version> must be '<major>.<minor>' or 'latest'.
883
884.. option:: -fcomment-block-commands=<arg>,<arg2>...
885
886Treat each comma separated argument in <arg> as a documentation comment block command
887
888.. option:: -fcomplete-member-pointers, -fno-complete-member-pointers
889
890Require member pointer base types to be complete if they would be significant under the Microsoft ABI
891
892.. option:: -fcrash-diagnostics-dir=<dir>
893
894Put crash-report files in <dir>
895
896.. option:: -fdeclspec, -fno-declspec
897
898Allow \_\_declspec as a keyword
899
900.. option:: -fdepfile-entry=<arg>
901
902.. option:: -fdiagnostics-fixit-info, -fno-diagnostics-fixit-info
903
904.. option:: -fdiagnostics-format=<arg>
905
906.. option:: -fdiagnostics-parseable-fixits
907
908Print fix-its in machine parseable form
909
910.. option:: -fdiagnostics-print-source-range-info
911
912Print source range spans in numeric form
913
914.. option:: -fdiagnostics-show-category=<arg>
915
916.. option:: -fdiscard-value-names, -fno-discard-value-names
917
918Discard value names in LLVM IR
919
920.. option:: -fexperimental-relative-c++-abi-vtables, -fno-experimental-relative-c++-abi-vtables
921
922Use the experimental C++ class ABI for classes with virtual tables
923
924.. option:: -fexperimental-strict-floating-point
925
926Enables experimental strict floating point in LLVM.
927
928.. option:: -ffine-grained-bitfield-accesses, -fno-fine-grained-bitfield-accesses
929
930Use separate accesses for consecutive bitfield runs with legal widths and alignments.
931
932.. option:: -fglobal-isel, -fexperimental-isel, -fno-global-isel
933
934Enables the global instruction selector
935
936.. option:: -finline-functions, -fno-inline-functions
937
938Inline suitable functions
939
940.. option:: -finline-hint-functions
941
942Inline functions which are (explicitly or implicitly) marked inline
943
944.. option:: -fno-legacy-pass-manager, -fexperimental-new-pass-manager
945
946.. option:: -fno-sanitize-ignorelist, -fno-sanitize-blacklist
947
948Don't use ignorelist file for sanitizers
949
950.. option:: -fparse-all-comments
951
952.. option:: -frandomize-layout-seed-file=<file>
953
954File holding the seed used by the randomize structure layout feature
955
956.. option:: -frandomize-layout-seed=<seed>
957
958The seed used by the randomize structure layout feature
959
960.. option:: -frecord-command-line, -fno-record-command-line, -frecord-gcc-switches
961
962.. option:: -fsanitize-address-destructor=<arg>
963
964Set destructor type used in ASan instrumentation. <arg> must be 'none' or 'global'.
965
966.. option:: -fsanitize-address-field-padding=<arg>
967
968Level of field padding for AddressSanitizer
969
970.. option:: -fsanitize-address-globals-dead-stripping, -fno-sanitize-address-globals-dead-stripping
971
972Enable linker dead stripping of globals in AddressSanitizer
973
974.. option:: -fsanitize-address-outline-instrumentation, -fno-sanitize-address-outline-instrumentation
975
976Always generate function calls for address sanitizer instrumentation
977
978.. option:: -fsanitize-address-poison-custom-array-cookie, -fno-sanitize-address-poison-custom-array-cookie
979
980Enable poisoning array cookies when using custom operator new\[\] in AddressSanitizer
981
982.. option:: -fsanitize-address-use-after-return=<mode>
983
984Select the mode of detecting stack use-after-return in AddressSanitizer. <mode> must be 'never', 'runtime' or 'always'.
985
986.. option:: -fsanitize-address-use-after-scope, -fno-sanitize-address-use-after-scope
987
988Enable use-after-scope detection in AddressSanitizer
989
990.. option:: -fsanitize-address-use-odr-indicator, -fno-sanitize-address-use-odr-indicator
991
992Enable ODR indicator globals to avoid false ODR violation reports in partially sanitized programs at the cost of an increase in binary size
993
994.. option:: -fsanitize-cfi-canonical-jump-tables, -fno-sanitize-cfi-canonical-jump-tables
995
996Make the jump table addresses canonical in the symbol table
997
998.. option:: -fsanitize-cfi-cross-dso, -fno-sanitize-cfi-cross-dso
999
1000Enable control flow integrity (CFI) checks for cross-DSO calls.
1001
1002.. option:: -fsanitize-cfi-icall-generalize-pointers
1003
1004Generalize pointers in CFI indirect call type signature checks
1005
1006.. option:: -fsanitize-coverage-allowlist=<arg>, -fsanitize-coverage-whitelist=<arg>
1007
1008Restrict sanitizer coverage instrumentation exclusively to modules and functions that match the provided special case list, except the blocked ones
1009
1010.. option:: -fsanitize-coverage-ignorelist=<arg>, -fsanitize-coverage-blacklist=<arg>
1011
1012Disable sanitizer coverage instrumentation for modules and functions that match the provided special case list, even the allowed ones
1013
1014.. option:: -fsanitize-coverage=<arg1>,<arg2>..., -fno-sanitize-coverage=<arg1>,<arg2>...
1015
1016Specify the type of coverage instrumentation for Sanitizers
1017
1018.. option:: -fsanitize-hwaddress-abi=<arg>
1019
1020Select the HWAddressSanitizer ABI to target (interceptor or platform, default interceptor). This option is currently unused.
1021
1022.. option:: -fsanitize-hwaddress-experimental-aliasing, -fno-sanitize-hwaddress-experimental-aliasing
1023
1024Enable aliasing mode in HWAddressSanitizer
1025
1026.. option:: -fsanitize-ignorelist=<arg>, -fsanitize-blacklist=<arg>
1027
1028Path to ignorelist file for sanitizers
1029
1030.. option:: -fsanitize-link-c++-runtime, -fno-sanitize-link-c++-runtime
1031
1032.. option:: -fsanitize-link-runtime, -fno-sanitize-link-runtime
1033
1034.. option:: -fsanitize-memory-track-origins, -fno-sanitize-memory-track-origins
1035
1036Enable origins tracking in MemorySanitizer
1037
1038.. program:: clang1
1039.. option:: -fsanitize-memory-track-origins=<arg>
1040.. program:: clang
1041
1042Enable origins tracking in MemorySanitizer
1043
1044.. option:: -fsanitize-memory-use-after-dtor, -fno-sanitize-memory-use-after-dtor
1045
1046Enable use-after-destroy detection in MemorySanitizer
1047
1048.. option:: -fsanitize-memtag-mode=<arg>
1049
1050Set default MTE mode to 'sync' (default) or 'async'
1051
1052.. option:: -fsanitize-minimal-runtime, -fno-sanitize-minimal-runtime
1053
1054.. option:: -fsanitize-recover=<arg1>,<arg2>..., -fno-sanitize-recover=<arg1>,<arg2>..., -fsanitize-recover (equivalent to -fsanitize-recover=all)
1055
1056Enable recovery for specified sanitizers
1057
1058.. option:: -fsanitize-stats, -fno-sanitize-stats
1059
1060Enable sanitizer statistics gathering.
1061
1062.. option:: -fsanitize-thread-atomics, -fno-sanitize-thread-atomics
1063
1064Enable atomic operations instrumentation in ThreadSanitizer (default)
1065
1066.. option:: -fsanitize-thread-func-entry-exit, -fno-sanitize-thread-func-entry-exit
1067
1068Enable function entry/exit instrumentation in ThreadSanitizer (default)
1069
1070.. option:: -fsanitize-thread-memory-access, -fno-sanitize-thread-memory-access
1071
1072Enable memory access instrumentation in ThreadSanitizer (default)
1073
1074.. option:: -fsanitize-trap=<arg1>,<arg2>..., -fno-sanitize-trap=<arg1>,<arg2>..., -fsanitize-trap (equivalent to -fsanitize-trap=all), -fsanitize-undefined-trap-on-error (equivalent to -fsanitize-trap=undefined)
1075
1076Enable trapping for specified sanitizers
1077
1078.. option:: -fsanitize-undefined-strip-path-components=<number>
1079
1080Strip (or keep only, if negative) a given number of path components when emitting check metadata.
1081
1082.. option:: -fsanitize=<check>,<arg2>..., -fno-sanitize=<arg1>,<arg2>...
1083
1084Turn on runtime checks for various forms of undefined or suspicious behavior. See user manual for available checks
1085
1086.. option:: -moutline, -mno-outline
1087
1088Enable function outlining (AArch64 only)
1089
1090.. option:: -moutline-atomics, -mno-outline-atomics
1091
1092Generate local calls to out-of-line atomic operations
1093
1094.. option:: --param <arg>, --param=<arg>
1095
1096.. option:: -print-supported-cpus, --print-supported-cpus, -mcpu=?, -mtune=?
1097
1098Print supported cpu models for the given target (if target is not specified, it will print the supported cpus for the default target)
1099
1100.. option:: -std=<arg>, --std=<arg>, --std <arg>
1101
1102Language standard to compile for
1103
1104Preprocessor flags
1105~~~~~~~~~~~~~~~~~~
1106
1107Flags controlling the behavior of the Clang preprocessor.
1108
1109.. option:: -C, --comments
1110
1111Include comments in preprocessed output
1112
1113.. option:: -CC, --comments-in-macros
1114
1115Include comments from within macros in preprocessed output
1116
1117.. program:: clang2
1118.. option:: -D<macro>=<value>, --D<arg>, /D<arg>, -D<arg>, --define-macro <arg>, --define-macro=<arg>
1119.. program:: clang
1120
1121Define <macro> to <value> (or 1 if <value> omitted)
1122
1123.. option:: -H, --trace-includes
1124
1125Show header includes and nesting depth
1126
1127.. option:: -P, --no-line-commands
1128
1129Disable linemarker output in -E mode
1130
1131.. option:: -U<macro>, --undefine-macro <arg>, --undefine-macro=<arg>
1132
1133Undefine macro <macro>
1134
1135.. option:: -Wp,<arg>,<arg2>...
1136
1137Pass the comma separated arguments in <arg> to the preprocessor
1138
1139.. option:: -Xpreprocessor <arg>
1140
1141Pass <arg> to the preprocessor
1142
1143Include path management
1144-----------------------
1145
1146Flags controlling how ``#include``\s are resolved to files.
1147
1148.. option:: -I<dir>, --include-directory <arg>, --include-directory=<arg>
1149
1150Add directory to include search path. For C++ inputs, if
1151there are multiple -I options, these directories are searched
1152in the order they are given before the standard system directories
1153are searched. If the same directory is in the SYSTEM include search
1154paths, for example if also specified with -isystem, the -I option
1155will be ignored
1156
1157.. option:: -I-, --include-barrier
1158
1159Restrict all prior -I flags to double-quoted inclusion and remove current directory from include path
1160
1161.. option:: --amdgpu-arch-tool=<arg>
1162
1163Tool used for detecting AMD GPU arch in the system.
1164
1165.. option:: --cuda-path-ignore-env
1166
1167Ignore environment variables to detect CUDA installation
1168
1169.. option:: --cuda-path=<arg>
1170
1171CUDA installation path
1172
1173.. option:: -cxx-isystem<directory>
1174
1175Add directory to the C++ SYSTEM include search path
1176
1177.. option:: -fbuild-session-file=<file>
1178
1179Use the last modification time of <file> as the build session timestamp
1180
1181.. option:: -fbuild-session-timestamp=<time since Epoch in seconds>
1182
1183Time when the current build session started
1184
1185.. option:: -fmodule-file=\[<name>=\]<file>
1186
1187Specify the mapping of module name to precompiled module file, or load a module file if name is omitted.
1188
1189.. option:: -fmodules-cache-path=<directory>
1190
1191Specify the module cache path
1192
1193.. option:: -fmodules-disable-diagnostic-validation
1194
1195Disable validation of the diagnostic options when loading the module
1196
1197.. option:: -fmodules-prune-after=<seconds>
1198
1199Specify the interval (in seconds) after which a module file will be considered unused
1200
1201.. option:: -fmodules-prune-interval=<seconds>
1202
1203Specify the interval (in seconds) between attempts to prune the module cache
1204
1205.. option:: -fmodules-user-build-path <directory>
1206
1207Specify the module user build path
1208
1209.. option:: -fmodules-validate-once-per-build-session
1210
1211Don't verify input files for the modules if the module has been successfully validated or loaded during this build session
1212
1213.. option:: -fmodules-validate-system-headers, -fno-modules-validate-system-headers
1214
1215Validate the system headers that a module depends on when loading the module
1216
1217.. option:: -fprebuilt-module-path=<directory>
1218
1219Specify the prebuilt module path
1220
1221.. option:: --hip-path=<arg>
1222
1223HIP runtime installation path, used for finding HIP version and adding HIP include path.
1224
1225.. option:: -idirafter<arg>, --include-directory-after <arg>, --include-directory-after=<arg>
1226
1227Add directory to AFTER include search path
1228
1229.. option:: -iframework<arg>
1230
1231Add directory to SYSTEM framework search path
1232
1233.. option:: -iframeworkwithsysroot<directory>
1234
1235Add directory to SYSTEM framework search path, absolute paths are relative to -isysroot
1236
1237.. option:: -imacros<file>, --imacros<file>, --imacros=<arg>
1238
1239Include macros from file before parsing
1240
1241.. option:: -include<file>, --include<file>, --include=<arg>
1242
1243Include file before parsing
1244
1245.. option:: -include-pch <file>
1246
1247Include precompiled header file
1248
1249.. option:: -iprefix<dir>, --include-prefix <arg>, --include-prefix=<arg>
1250
1251Set the -iwithprefix/-iwithprefixbefore prefix
1252
1253.. option:: -iquote<directory>
1254
1255Add directory to QUOTE include search path
1256
1257.. option:: -isysroot<dir>
1258
1259Set the system root directory (usually /)
1260
1261.. option:: -isystem<directory>
1262
1263Add directory to SYSTEM include search path
1264
1265.. option:: -isystem-after<directory>
1266
1267Add directory to end of the SYSTEM include search path
1268
1269.. option:: -ivfsoverlay<arg>
1270
1271Overlay the virtual filesystem described by file over the real file system
1272
1273.. option:: -iwithprefix<dir>, --include-with-prefix <arg>, --include-with-prefix-after <arg>, --include-with-prefix-after=<arg>, --include-with-prefix=<arg>
1274
1275Set directory to SYSTEM include search path with prefix
1276
1277.. option:: -iwithprefixbefore<dir>, --include-with-prefix-before <arg>, --include-with-prefix-before=<arg>
1278
1279Set directory to include search path with prefix
1280
1281.. option:: -iwithsysroot<directory>
1282
1283Add directory to SYSTEM include search path, absolute paths are relative to -isysroot
1284
1285.. option:: --libomptarget-amdgpu-bc-path=<arg>, --libomptarget-amdgcn-bc-path=<arg>
1286
1287Path to libomptarget-amdgcn bitcode library
1288
1289.. option:: --libomptarget-nvptx-bc-path=<arg>
1290
1291Path to libomptarget-nvptx bitcode library
1292
1293.. option:: --ptxas-path=<arg>
1294
1295Path to ptxas (used for compiling CUDA code)
1296
1297.. option:: --rocm-path=<arg>
1298
1299ROCm installation path, used for finding and automatically linking required bitcode libraries.
1300
1301.. program:: clang1
1302.. option:: -stdlib++-isystem<directory>
1303.. program:: clang
1304
1305Use directory as the C++ standard library include path
1306
1307.. option:: --system-header-prefix=<prefix>, --no-system-header-prefix=<prefix>, --system-header-prefix <arg>
1308
1309Treat all #include paths starting with <prefix> as including a system header.
1310
1311Dependency file generation
1312--------------------------
1313
1314Flags controlling generation of a dependency file for ``make``-like build
1315systems.
1316
1317.. option:: -M, --dependencies
1318
1319Like -MD, but also implies -E and writes to stdout by default
1320
1321.. option:: -MD, --write-dependencies
1322
1323Write a depfile containing user and system headers
1324
1325.. option:: -MF<file>
1326
1327Write depfile output from -MMD, -MD, -MM, or -M to <file>
1328
1329.. option:: -MG, --print-missing-file-dependencies
1330
1331Add missing headers to depfile
1332
1333.. option:: -MJ<arg>
1334
1335Write a compilation database entry per input
1336
1337.. option:: -MM, --user-dependencies
1338
1339Like -MMD, but also implies -E and writes to stdout by default
1340
1341.. option:: -MMD, --write-user-dependencies
1342
1343Write a depfile containing user headers
1344
1345.. option:: -MP
1346
1347Create phony target for each dependency (other than main file)
1348
1349.. option:: -MQ<arg>
1350
1351Specify name of main file output to quote in depfile
1352
1353.. option:: -MT<arg>
1354
1355Specify name of main file output in depfile
1356
1357.. option:: -MV
1358
1359Use NMake/Jom format for the depfile
1360
1361Dumping preprocessor state
1362--------------------------
1363
1364Flags allowing the state of the preprocessor to be dumped in various ways.
1365
1366.. option:: -d
1367
1368.. program:: clang1
1369.. option:: -d<arg>
1370.. program:: clang
1371
1372.. option:: -dD
1373
1374Print macro definitions in -E mode in addition to normal output
1375
1376.. option:: -dI
1377
1378Print include directives in -E mode in addition to normal output
1379
1380.. option:: -dM
1381
1382Print macro definitions in -E mode instead of normal output
1383
1384Diagnostic flags
1385~~~~~~~~~~~~~~~~
1386
1387Flags controlling which warnings, errors, and remarks Clang will generate.
1388See the :doc:`full list of warning and remark flags <DiagnosticsReference>`.
1389
1390.. option:: -R<remark>
1391
1392Enable the specified remark
1393
1394.. option:: -Rpass-analysis=<arg>
1395
1396Report transformation analysis from optimization passes whose name matches the given POSIX regular expression
1397
1398.. option:: -Rpass-missed=<arg>
1399
1400Report missed transformations by optimization passes whose name matches the given POSIX regular expression
1401
1402.. option:: -Rpass=<arg>
1403
1404Report transformations performed by optimization passes whose name matches the given POSIX regular expression
1405
1406.. option:: -W<warning>, --extra-warnings, --warn-<arg>, --warn-=<arg>
1407
1408Enable the specified warning
1409
1410.. option:: -Wdeprecated, -Wno-deprecated
1411
1412Enable warnings for deprecated constructs and define \_\_DEPRECATED
1413
1414.. option:: -Wframe-larger-than=<arg>, -Wframe-larger-than
1415
1416.. option:: -Wnonportable-cfstrings<arg>, -Wno-nonportable-cfstrings<arg>
1417
1418Target-independent compilation options
1419~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1420.. option:: -fPIC, -fno-PIC
1421
1422.. option:: -fPIE, -fno-PIE
1423
1424.. option:: -faccess-control, -fno-access-control
1425
1426.. option:: -faddrsig, -fno-addrsig
1427
1428Emit an address-significance table
1429
1430.. option:: -falign-functions, -fno-align-functions
1431
1432.. program:: clang1
1433.. option:: -falign-functions=<arg>
1434.. program:: clang
1435
1436.. option:: -falign-loops=<N>
1437
1438N must be a power of two. Align loops to the boundary
1439
1440.. program:: clang1
1441.. option:: -faligned-allocation, -faligned-new, -fno-aligned-allocation
1442.. program:: clang
1443
1444Enable C++17 aligned allocation functions
1445
1446.. option:: -fallow-editor-placeholders, -fno-allow-editor-placeholders
1447
1448Treat editor placeholders as valid source code
1449
1450.. option:: -fallow-unsupported
1451
1452.. option:: -faltivec, -fno-altivec
1453
1454.. option:: -faltivec-src-compat=<arg>
1455
1456Source-level compatibility for Altivec vectors (for PowerPC targets). This includes results of vector comparison (scalar for 'xl', vector for 'gcc') as well as behavior when initializing with a scalar (splatting for 'xl', element zero only for 'gcc'). For 'mixed', the compatibility is as 'gcc' for 'vector bool/vector pixel' and as 'xl' for other types. Current default is 'mixed'. <arg> must be 'mixed', 'gcc' or 'xl'.
1457
1458.. option:: -fansi-escape-codes
1459
1460Use ANSI escape codes for diagnostics
1461
1462.. option:: -fapple-kext, -findirect-virtual-calls, -fterminated-vtables
1463
1464Use Apple's kernel extensions ABI
1465
1466.. option:: -fapple-link-rtlib
1467
1468Force linking the clang builtins runtime library
1469
1470.. option:: -fapple-pragma-pack, -fno-apple-pragma-pack
1471
1472Enable Apple gcc-compatible #pragma pack handling
1473
1474.. option:: -fapplication-extension, -fno-application-extension
1475
1476Restrict code to those available for App Extensions
1477
1478.. option:: -fapprox-func, -fno-approx-func
1479
1480Allow certain math function calls to be replaced with an approximately equivalent calculation
1481
1482.. option:: -fasm, -fno-asm
1483
1484.. option:: -fasm-blocks, -fno-asm-blocks
1485
1486.. option:: -fassociative-math, -fno-associative-math
1487
1488.. option:: -fassume-sane-operator-new, -fno-assume-sane-operator-new
1489
1490.. option:: -fast
1491
1492.. option:: -fastcp
1493
1494.. option:: -fastf
1495
1496.. option:: -fasync-exceptions, -fno-async-exceptions
1497
1498Enable EH Asynchronous exceptions
1499
1500.. option:: -fasynchronous-unwind-tables, -fno-asynchronous-unwind-tables
1501
1502.. option:: -fautolink, -fno-autolink
1503
1504.. option:: -fbasic-block-sections=<arg>
1505
1506Generate labels for each basic block or place each basic block or a subset of basic blocks in its own section. <arg> must be 'all', 'labels', 'none' or 'list='.
1507
1508.. option:: -fbinutils-version=<major.minor>
1509
1510Produced object files can use all ELF features supported by this binutils version and newer. If -fno-integrated-as is specified, the generated assembly will consider GNU as support. 'none' means that all ELF features can be used, regardless of binutils support. Defaults to 2.26.
1511
1512.. option:: -fblocks, -fno-blocks
1513
1514Enable the 'blocks' language feature
1515
1516.. option:: -fbootclasspath=<arg>, --bootclasspath <arg>, --bootclasspath=<arg>
1517
1518.. option:: -fborland-extensions, -fno-borland-extensions
1519
1520Accept non-standard constructs supported by the Borland compiler
1521
1522.. option:: -fbracket-depth=<arg>
1523
1524.. option:: -fbuiltin, -fno-builtin
1525
1526.. option:: -fbuiltin-module-map
1527
1528Load the clang builtins module map file.
1529
1530.. program:: clang1
1531.. option:: -fc++-static-destructors, -fno-c++-static-destructors
1532.. program:: clang
1533
1534.. option:: -fcaret-diagnostics, -fno-caret-diagnostics
1535
1536.. option:: -fcf-protection=<arg>, -fcf-protection (equivalent to -fcf-protection=full)
1537
1538Instrument control-flow architecture protection. <arg> must be 'return', 'branch', 'full' or 'none'.
1539
1540.. option:: -fcf-runtime-abi=<arg>
1541
1542 <arg> must be 'unspecified', 'standalone', 'objc', 'swift', 'swift-5.0', 'swift-4.2' or 'swift-4.1'.
1543
1544.. option:: -fchar8\_t, -fno-char8\_t
1545
1546Enable C++ builtin type char8\_t
1547
1548.. option:: -fclasspath=<arg>, --CLASSPATH <arg>, --CLASSPATH=<arg>, --classpath <arg>, --classpath=<arg>
1549
1550.. option:: -fcolor-diagnostics, -fdiagnostics-color, -fno-color-diagnostics
1551
1552Enable colors in diagnostics
1553
1554.. option:: -fcommon, -fno-common
1555
1556Place uninitialized global variables in a common block
1557
1558.. option:: -fcompile-resource=<arg>, --resource <arg>, --resource=<arg>
1559
1560.. option:: -fconstant-cfstrings, -fno-constant-cfstrings
1561
1562.. option:: -fconstant-string-class=<arg>
1563
1564.. option:: -fconstexpr-backtrace-limit=<arg>
1565
1566.. option:: -fconstexpr-depth=<arg>
1567
1568.. option:: -fconstexpr-steps=<arg>
1569
1570.. option:: -fconvergent-functions
1571
1572Assume functions may be convergent
1573
1574.. option:: -fcoroutines-ts, -fno-coroutines-ts
1575
1576Enable support for the C++ Coroutines TS
1577
1578.. option:: -fcoverage-compilation-dir=<arg>
1579
1580The compilation directory to embed in the coverage mapping.
1581
1582.. option:: -fcoverage-mapping, -fno-coverage-mapping
1583
1584Generate coverage mapping to enable code coverage analysis
1585
1586.. option:: -fcoverage-prefix-map=<arg>
1587
1588remap file source paths in coverage mapping
1589
1590.. option:: -fcreate-profile
1591
1592.. option:: -fcs-profile-generate
1593
1594Generate instrumented code to collect context sensitive execution counts into default.profraw (overridden by LLVM\_PROFILE\_FILE env var)
1595
1596.. program:: clang1
1597.. option:: -fcs-profile-generate=<directory>
1598.. program:: clang
1599
1600Generate instrumented code to collect context sensitive execution counts into <directory>/default.profraw (overridden by LLVM\_PROFILE\_FILE env var)
1601
1602.. option:: -fcuda-approx-transcendentals, -fno-cuda-approx-transcendentals
1603
1604Use approximate transcendental functions
1605
1606.. option:: -fcuda-short-ptr, -fno-cuda-short-ptr
1607
1608Use 32-bit pointers for accessing const/local/shared address spaces
1609
1610.. option:: -fcxx-exceptions, -fno-cxx-exceptions
1611
1612Enable C++ exceptions
1613
1614.. option:: -fcxx-modules, -fno-cxx-modules
1615
1616Enable modules for C++
1617
1618.. option:: -fdata-sections, -fno-data-sections
1619
1620Place each data in its own section
1621
1622.. option:: -fdebug-compilation-dir=<arg>, -fdebug-compilation-dir <arg>
1623
1624The compilation directory to embed in the debug info
1625
1626.. option:: -fdebug-default-version=<arg>
1627
1628Default DWARF version to use, if a -g option caused DWARF debug info to be produced
1629
1630.. option:: -fdebug-info-for-profiling, -fno-debug-info-for-profiling
1631
1632Emit extra debug info to make sample profile more accurate
1633
1634.. option:: -fdebug-macro, -fno-debug-macro
1635
1636Emit macro debug information
1637
1638.. option:: -fdebug-pass-arguments
1639
1640.. option:: -fdebug-pass-structure
1641
1642.. option:: -fdebug-prefix-map=<arg>
1643
1644remap file source paths in debug info
1645
1646.. option:: -fdebug-ranges-base-address, -fno-debug-ranges-base-address
1647
1648Use DWARF base address selection entries in .debug\_ranges
1649
1650.. option:: -fdebug-types-section, -fno-debug-types-section
1651
1652Place debug types in their own section (ELF Only)
1653
1654.. option:: -fdelayed-template-parsing, -fno-delayed-template-parsing
1655
1656Parse templated function definitions at the end of the translation unit
1657
1658.. option:: -fdelete-null-pointer-checks, -fno-delete-null-pointer-checks
1659
1660Treat usage of null pointers as undefined behavior (default)
1661
1662.. option:: -fdenormal-fp-math=<arg>
1663
1664.. option:: -fdiagnostics-absolute-paths
1665
1666Print absolute paths in diagnostics
1667
1668.. program:: clang1
1669.. option:: -fdiagnostics-color=<arg>
1670.. program:: clang
1671
1672.. option:: -fdiagnostics-hotness-threshold=<value>
1673
1674Prevent optimization remarks from being output if they do not have at least this profile count. Use 'auto' to apply the threshold from profile summary
1675
1676.. option:: -fdiagnostics-misexpect-tolerance=<value>
1677
1678Prevent misexpect diagnostics from being output if the profile counts are within N% of the expected.
1679
1680.. option:: -fdiagnostics-show-hotness, -fno-diagnostics-show-hotness
1681
1682Enable profile hotness information in diagnostic line
1683
1684.. option:: -fdiagnostics-show-note-include-stack, -fno-diagnostics-show-note-include-stack
1685
1686Display include stacks for diagnostic notes
1687
1688.. option:: -fdiagnostics-show-option, -fno-diagnostics-show-option
1689
1690Print option name with mappable diagnostics
1691
1692.. option:: -fdiagnostics-show-template-tree
1693
1694Print a template comparison tree for differing templates
1695
1696.. option:: -fdigraphs, -fno-digraphs
1697
1698Enable alternative token representations '<:', ':>', '<%', '%>', '%:', '%:%:' (default)
1699
1700.. option:: -fdirect-access-external-data, -fno-direct-access-external-data
1701
1702Don't use GOT indirection to reference external data symbols
1703
1704.. option:: -fdirectives-only, -fno-directives-only
1705
1706.. option:: -fdollars-in-identifiers, -fno-dollars-in-identifiers
1707
1708Allow '$' in identifiers
1709
1710.. option:: -fdouble-square-bracket-attributes, -fno-double-square-bracket-attributes
1711
1712Enable '\[\[\]\]' attributes in all C and C++ language modes
1713
1714.. option:: -fdwarf-directory-asm, -fno-dwarf-directory-asm
1715
1716.. option:: -fdwarf-exceptions
1717
1718Use DWARF style exceptions
1719
1720.. option:: -felide-constructors, -fno-elide-constructors
1721
1722.. option:: -feliminate-unused-debug-symbols, -fno-eliminate-unused-debug-symbols
1723
1724.. option:: -feliminate-unused-debug-types, -fno-eliminate-unused-debug-types
1725
1726Do not emit  debug info for defined but unused types
1727
1728.. option:: -fembed-bitcode=<option>, -fembed-bitcode (equivalent to -fembed-bitcode=all), -fembed-bitcode-marker (equivalent to -fembed-bitcode=marker)
1729
1730Embed LLVM bitcode. <option> must be 'off', 'all', 'bitcode' or 'marker'.
1731
1732.. option:: -fembed-offload-object=<arg>
1733
1734Embed Offloading device-side binary into host object file as a section.
1735
1736.. option:: -femit-all-decls
1737
1738Emit all declarations, even if unused
1739
1740.. option:: -femit-dwarf-unwind=<arg>
1741
1742When to emit DWARF unwind (EH frame) info. <arg> must be 'always', 'no-compact-unwind' or 'default'.
1743
1744.. option:: -femulated-tls, -fno-emulated-tls
1745
1746Use emutls functions to access thread\_local variables
1747
1748.. option:: -fenable-matrix
1749
1750Enable matrix data type and related builtin functions
1751
1752.. option:: -fencoding=<arg>, --encoding <arg>, --encoding=<arg>
1753
1754.. option:: -ferror-limit=<arg>
1755
1756.. option:: -fescaping-block-tail-calls, -fno-escaping-block-tail-calls
1757
1758.. option:: -fexceptions, -fno-exceptions
1759
1760Enable support for exception handling
1761
1762.. option:: -fexec-charset=<arg>
1763
1764.. option:: -fexperimental-new-constant-interpreter
1765
1766Enable the experimental new constant interpreter
1767
1768.. option:: -fextdirs=<arg>, --extdirs <arg>, --extdirs=<arg>
1769
1770.. option:: -fextend-arguments=<arg>
1771
1772Controls how scalar integer arguments are extended in calls to unprototyped and varargs functions. <arg> must be '32' or '64'.
1773
1774.. option:: -ffast-math, -fno-fast-math
1775
1776Allow aggressive, lossy floating-point optimizations
1777
1778.. option:: -ffile-compilation-dir=<arg>
1779
1780The compilation directory to embed in the debug info and coverage mapping.
1781
1782.. option:: -ffile-prefix-map=<arg>
1783
1784remap file source paths in debug info, predefined preprocessor macros and \_\_builtin\_FILE(). Implies -ffile-reproducible.
1785
1786.. option:: -ffile-reproducible, -fno-file-reproducible
1787
1788Use the target's platform-specific path separator character when expanding the \_\_FILE\_\_ macro
1789
1790.. option:: -ffinite-loops, -fno-finite-loops
1791
1792Assume all loops are finite.
1793
1794.. option:: -ffinite-math-only, -fno-finite-math-only
1795
1796.. option:: -ffixed-point, -fno-fixed-point
1797
1798Enable fixed point types
1799
1800.. option:: -ffor-scope, -fno-for-scope
1801
1802.. option:: -fforce-dwarf-frame, -fno-force-dwarf-frame
1803
1804Always emit a debug frame section
1805
1806.. option:: -fforce-emit-vtables, -fno-force-emit-vtables
1807
1808Emits more virtual tables to improve devirtualization
1809
1810.. option:: -fforce-enable-int128, -fno-force-enable-int128
1811
1812Enable support for int128\_t type
1813
1814.. option:: -ffp-contract=<arg>
1815
1816Form fused FP ops (e.g. FMAs): fast (fuses across statements disregarding pragmas) \| on (only fuses in the same statement unless dictated by pragmas) \| off (never fuses) \| fast-honor-pragmas (fuses across statements unless diectated by pragmas). Default is 'fast' for CUDA, 'fast-honor-pragmas' for HIP, and 'on' otherwise. <arg> must be 'fast', 'on', 'off' or 'fast-honor-pragmas'.
1817
1818.. option:: -ffp-eval-method=<arg>
1819
1820Specifies the evaluation method to use for floating-point arithmetic. <arg> must be 'source', 'double' or 'extended'.
1821
1822.. option:: -ffp-exception-behavior=<arg>
1823
1824Specifies the exception behavior of floating-point operations. <arg> must be 'ignore', 'maytrap' or 'strict'.
1825
1826.. option:: -ffp-model=<arg>
1827
1828Controls the semantics of floating-point calculations.
1829
1830.. option:: -ffreestanding
1831
1832Assert that the compilation takes place in a freestanding environment
1833
1834.. option:: -ffunction-sections, -fno-function-sections
1835
1836Place each function in its own section
1837
1838.. option:: -fgnu-inline-asm, -fno-gnu-inline-asm
1839
1840.. option:: -fgnu-keywords, -fno-gnu-keywords
1841
1842Allow GNU-extension keywords regardless of language standard
1843
1844.. option:: -fgnu-runtime
1845
1846Generate output compatible with the standard GNU Objective-C runtime
1847
1848.. option:: -fgnu89-inline, -fno-gnu89-inline
1849
1850Use the gnu89 inline semantics
1851
1852.. option:: -fgnuc-version=<arg>
1853
1854Sets various macros to claim compatibility with the given GCC version (default is 4.2.1)
1855
1856.. option:: -fgpu-allow-device-init, -fno-gpu-allow-device-init
1857
1858Allow device side init function in HIP (experimental)
1859
1860.. option:: -fgpu-defer-diag, -fno-gpu-defer-diag
1861
1862Defer host/device related diagnostic messages for CUDA/HIP
1863
1864.. option:: -fgpu-rdc, -fcuda-rdc, -fno-gpu-rdc
1865
1866Generate relocatable device code, also known as separate compilation mode
1867
1868.. option:: -fgpu-sanitize, -fno-gpu-sanitize
1869
1870Enable sanitizer for AMDGPU target
1871
1872.. option:: -fhip-fp32-correctly-rounded-divide-sqrt, -fno-hip-fp32-correctly-rounded-divide-sqrt
1873
1874Specify that single precision floating-point divide and sqrt used in the program source are correctly rounded (HIP device compilation only)
1875
1876.. option:: -fhip-kernel-arg-name, -fno-hip-kernel-arg-name
1877
1878Specify that kernel argument names are preserved (HIP only)
1879
1880.. option:: -fhip-new-launch-api, -fno-hip-new-launch-api
1881
1882Use new kernel launching API for HIP
1883
1884.. option:: -fhonor-infinities, -fhonor-infinites, -fno-honor-infinities
1885
1886.. option:: -fhonor-nans, -fno-honor-nans
1887
1888.. option:: -fhosted
1889
1890.. option:: -fignore-exceptions
1891
1892Enable support for ignoring exception handling constructs
1893
1894.. option:: -fimplicit-module-maps, -fmodule-maps, -fno-implicit-module-maps
1895
1896Implicitly search the file system for module map files.
1897
1898.. option:: -fimplicit-modules, -fno-implicit-modules
1899
1900.. option:: -finput-charset=<arg>
1901
1902Specify the default character set for source files
1903
1904.. option:: -finstrument-function-entry-bare
1905
1906Instrument function entry only, after inlining, without arguments to the instrumentation call
1907
1908.. option:: -finstrument-functions
1909
1910Generate calls to instrument function entry and exit
1911
1912.. option:: -finstrument-functions-after-inlining
1913
1914Like -finstrument-functions, but insert the calls after inlining
1915
1916.. option:: -fintegrated-as, -fno-integrated-as, -integrated-as
1917
1918Enable the integrated assembler
1919
1920.. option:: -fintegrated-cc1, -fno-integrated-cc1
1921
1922Run cc1 in-process
1923
1924.. option:: -fintegrated-objemitter, -fno-integrated-objemitter
1925
1926Use internal machine object code emitter.
1927
1928.. option:: -fjmc, -fno-jmc
1929
1930Enable just-my-code debugging
1931
1932.. option:: -fjump-tables, -fno-jump-tables
1933
1934Use jump tables for lowering switches
1935
1936.. option:: -fkeep-static-consts, -fno-keep-static-consts
1937
1938Keep static const variables if unused
1939
1940.. option:: -flax-vector-conversions=<arg>, -flax-vector-conversions (equivalent to -flax-vector-conversions=integer), -fno-lax-vector-conversions (equivalent to -flax-vector-conversions=none)
1941
1942Enable implicit vector bit-casts. <arg> must be 'none', 'integer' or 'all'.
1943
1944.. option:: -flimited-precision=<arg>
1945
1946.. option:: -flto-jobs=<arg>
1947
1948Controls the backend parallelism of -flto=thin (default of 0 means the number of threads will be derived from the number of CPUs detected)
1949
1950.. option:: -flto=<arg>, -flto (equivalent to -flto=full), -flto=auto (equivalent to -flto=full), -flto=jobserver (equivalent to -flto=full)
1951
1952Set LTO mode. <arg> must be 'thin' or 'full'.
1953
1954.. option:: -fmacro-backtrace-limit=<arg>
1955
1956.. option:: -fmacro-prefix-map=<arg>
1957
1958remap file source paths in predefined preprocessor macros and \_\_builtin\_FILE(). Implies -ffile-reproducible.
1959
1960.. option:: -fmath-errno, -fno-math-errno
1961
1962Require math functions to indicate errors by setting errno
1963
1964.. option:: -fmax-tokens=<arg>
1965
1966Max total number of preprocessed tokens for -Wmax-tokens.
1967
1968.. option:: -fmax-type-align=<arg>
1969
1970Specify the maximum alignment to enforce on pointers lacking an explicit alignment
1971
1972.. option:: -fmemory-profile, -fno-memory-profile
1973
1974Enable heap memory profiling
1975
1976.. program:: clang1
1977.. option:: -fmemory-profile=<directory>
1978.. program:: clang
1979
1980Enable heap memory profiling and dump results into <directory>
1981
1982.. option:: -fmerge-all-constants, -fno-merge-all-constants
1983
1984Allow merging of constants
1985
1986.. option:: -fmessage-length=<arg>
1987
1988Format message diagnostics so that they fit within N columns
1989
1990.. option:: -fminimize-whitespace, -fno-minimize-whitespace
1991
1992Minimize whitespace when emitting preprocessor output
1993
1994.. option:: -fmodule-file-deps, -fno-module-file-deps
1995
1996.. option:: -fmodule-header
1997
1998Build a C++20 Header Unit from a header.
1999
2000.. program:: clang1
2001.. option:: -fmodule-header=<kind>
2002.. program:: clang
2003
2004Build a C++20 Header Unit from a header that should be found in the user (fmodule-header=user) or system (fmodule-header=system) search path.
2005
2006.. option:: -fmodule-map-file=<file>
2007
2008Load this module map file
2009
2010.. option:: -fmodule-name=<name>, -fmodule-implementation-of <arg>
2011
2012Specify the name of the module to build
2013
2014.. option:: -fmodules, -fno-modules
2015
2016Enable the 'modules' language feature
2017
2018.. option:: -fmodules-decluse, -fno-modules-decluse
2019
2020Require declaration of modules used within a module
2021
2022.. option:: -fmodules-ignore-macro=<arg>
2023
2024Ignore the definition of the given macro when building and loading modules
2025
2026.. option:: -fmodules-search-all, -fno-modules-search-all
2027
2028Search even non-imported modules to resolve references
2029
2030.. option:: -fmodules-strict-decluse
2031
2032Like -fmodules-decluse but requires all headers to be in modules
2033
2034.. option:: -fmodules-ts
2035
2036Enable support for the C++ Modules TS
2037
2038.. option:: -fmodules-validate-input-files-content
2039
2040Validate PCM input files based on content if mtime differs
2041
2042.. option:: -fms-compatibility, -fno-ms-compatibility
2043
2044Enable full Microsoft Visual C++ compatibility
2045
2046.. option:: -fms-compatibility-version=<arg>
2047
2048Dot-separated value representing the Microsoft compiler version number to report in \_MSC\_VER (0 = don't define it (default))
2049
2050.. option:: -fms-extensions, -fno-ms-extensions
2051
2052Accept some non-standard constructs supported by the Microsoft compiler
2053
2054.. option:: -fms-hotpatch
2055
2056Ensure that all functions can be hotpatched at runtime
2057
2058.. option:: -fms-memptr-rep=<arg>
2059
2060 <arg> must be 'single', 'multiple' or 'virtual'.
2061
2062.. option:: -fms-volatile
2063
2064.. option:: -fmsc-version=<arg>
2065
2066Microsoft compiler version number to report in \_MSC\_VER (0 = don't define it (default))
2067
2068.. option:: -fmudflap
2069
2070.. option:: -fmudflapth
2071
2072.. option:: -fnested-functions
2073
2074.. option:: -fnew-alignment=<align>, -fnew-alignment <arg>
2075
2076Specifies the largest alignment guaranteed by '::operator new(size\_t)'
2077
2078.. option:: -fnew-infallible, -fno-new-infallible
2079
2080Enable treating throwing global C++ operator new as always returning valid memory (annotates with \_\_attribute\_\_((returns\_nonnull)) and throw()). This is detectable in source.
2081
2082.. option:: -fnext-runtime
2083
2084.. option:: -fno-builtin-<arg>
2085
2086Disable implicit builtin knowledge of a specific function
2087
2088.. option:: -fno-elide-type
2089
2090Do not elide types when printing diagnostics
2091
2092.. option:: -fno-knr-functions
2093
2094Disable support for K&R C function declarations
2095
2096.. option:: -fno-max-type-align
2097
2098.. option:: -fno-strict-modules-decluse
2099
2100.. option:: -fno-temp-file
2101
2102Directly create compilation output files. This may lead to incorrect incremental builds if the compiler crashes
2103
2104.. option:: -fno-working-directory
2105
2106.. option:: -fno\_modules-validate-input-files-content
2107
2108.. program:: clang1
2109.. option:: -fno\_pch-validate-input-files-content
2110.. program:: clang
2111
2112.. option:: -fnoxray-link-deps
2113
2114.. option:: -fobjc-abi-version=<arg>
2115
2116.. option:: -fobjc-arc, -fno-objc-arc
2117
2118Synthesize retain and release calls for Objective-C pointers
2119
2120.. option:: -fobjc-arc-exceptions, -fno-objc-arc-exceptions
2121
2122Use EH-safe code when synthesizing retains and releases in -fobjc-arc
2123
2124.. option:: -fobjc-convert-messages-to-runtime-calls, -fno-objc-convert-messages-to-runtime-calls
2125
2126.. option:: -fobjc-disable-direct-methods-for-testing
2127
2128Ignore attribute objc\_direct so that direct methods can be tested
2129
2130.. option:: -fobjc-encode-cxx-class-template-spec, -fno-objc-encode-cxx-class-template-spec
2131
2132Fully encode c++ class template specialization
2133
2134.. option:: -fobjc-exceptions, -fno-objc-exceptions
2135
2136Enable Objective-C exceptions
2137
2138.. option:: -fobjc-infer-related-result-type, -fno-objc-infer-related-result-type
2139
2140.. option:: -fobjc-legacy-dispatch, -fno-objc-legacy-dispatch
2141
2142.. option:: -fobjc-link-runtime
2143
2144.. option:: -fobjc-nonfragile-abi, -fno-objc-nonfragile-abi
2145
2146.. option:: -fobjc-nonfragile-abi-version=<arg>
2147
2148.. option:: -fobjc-runtime=<arg>
2149
2150Specify the target Objective-C runtime kind and version
2151
2152.. option:: -fobjc-sender-dependent-dispatch
2153
2154.. option:: -fobjc-weak, -fno-objc-weak
2155
2156Enable ARC-style weak references in Objective-C
2157
2158.. option:: -foffload-lto=<arg>, -foffload-lto (equivalent to -foffload-lto=full)
2159
2160Set LTO mode for offload compilation. <arg> must be 'thin' or 'full'.
2161
2162.. option:: -fomit-frame-pointer, -fno-omit-frame-pointer
2163
2164.. option:: -fopenmp, -fno-openmp
2165
2166Parse OpenMP pragmas and generate parallel code.
2167
2168.. option:: -fopenmp-extensions, -fno-openmp-extensions
2169
2170Enable all Clang extensions for OpenMP directives and clauses
2171
2172.. option:: -fopenmp-implicit-rpath, -fno-openmp-implicit-rpath
2173
2174Set rpath on OpenMP executables
2175
2176.. option:: -fopenmp-new-driver
2177
2178Use the new driver for OpenMP offloading.
2179
2180.. option:: -fopenmp-offload-mandatory
2181
2182Do not create a host fallback if offloading to the device fails.
2183
2184.. option:: -fopenmp-simd, -fno-openmp-simd
2185
2186Emit OpenMP code only for SIMD-based constructs.
2187
2188.. option:: -fopenmp-target-debug, -fno-openmp-target-debug
2189
2190Enable debugging in the OpenMP offloading device RTL
2191
2192.. option:: -fopenmp-version=<arg>
2193
2194Set OpenMP version (e.g. 45 for OpenMP 4.5, 50 for OpenMP 5.0). Default value is 50.
2195
2196.. program:: clang1
2197.. option:: -fopenmp=<arg>
2198.. program:: clang
2199
2200.. option:: -foperator-arrow-depth=<arg>
2201
2202.. option:: -foperator-names, -fno-operator-names
2203
2204.. option:: -foptimization-record-file=<file>
2205
2206Specify the output name of the file containing the optimization remarks. Implies -fsave-optimization-record. On Darwin platforms, this cannot be used with multiple -arch <arch> options.
2207
2208.. option:: -foptimization-record-passes=<regex>
2209
2210Only include passes which match a specified regular expression in the generated optimization record (by default, include all passes)
2211
2212.. option:: -foptimize-sibling-calls, -fno-optimize-sibling-calls
2213
2214.. option:: -forder-file-instrumentation
2215
2216Generate instrumented code to collect order file into default.profraw file (overridden by '=' form of option or LLVM\_PROFILE\_FILE env var)
2217
2218.. option:: -foutput-class-dir=<arg>, --output-class-directory <arg>, --output-class-directory=<arg>
2219
2220.. option:: -fpack-struct, -fno-pack-struct
2221
2222.. program:: clang1
2223.. option:: -fpack-struct=<arg>
2224.. program:: clang
2225
2226Specify the default maximum struct packing alignment
2227
2228.. option:: -fpascal-strings, -fno-pascal-strings, -mpascal-strings
2229
2230Recognize and construct Pascal-style string literals
2231
2232.. option:: -fpass-plugin=<dsopath>
2233
2234Load pass plugin from a dynamic shared object file (only with new pass manager).
2235
2236.. option:: -fpatchable-function-entry=<N,M>
2237
2238Generate M NOPs before function entry and N-M NOPs after function entry
2239
2240.. option:: -fpcc-struct-return
2241
2242Override the default ABI to return all structs on the stack
2243
2244.. option:: -fpch-codegen, -fno-pch-codegen
2245
2246Generate code for uses of this PCH that assumes an explicit object file will be built for the PCH
2247
2248.. option:: -fpch-debuginfo, -fno-pch-debuginfo
2249
2250Generate debug info for types in an object file built from this PCH and do not generate them elsewhere
2251
2252.. option:: -fpch-instantiate-templates, -fno-pch-instantiate-templates
2253
2254Instantiate templates already while building a PCH
2255
2256.. option:: -fpch-preprocess
2257
2258.. option:: -fpch-validate-input-files-content
2259
2260Validate PCH input files based on content if mtime differs
2261
2262.. option:: -fpic, -fno-pic
2263
2264.. option:: -fpie, -fno-pie
2265
2266.. option:: -fplt, -fno-plt
2267
2268.. option:: -fplugin=<dsopath>
2269
2270Load the named plugin (dynamic shared object)
2271
2272.. option:: -fprebuilt-implicit-modules, -fno-prebuilt-implicit-modules
2273
2274Look up implicit modules in the prebuilt module path
2275
2276.. option:: -fpreserve-as-comments, -fno-preserve-as-comments
2277
2278.. option:: -fproc-stat-report<arg>
2279
2280Print subprocess statistics
2281
2282.. program:: clang1
2283.. option:: -fproc-stat-report=<arg>
2284.. program:: clang
2285
2286Save subprocess statistics to the given file
2287
2288.. option:: -fprofile-arcs, -fno-profile-arcs
2289
2290.. option:: -fprofile-dir=<arg>
2291
2292.. option:: -fprofile-exclude-files=<arg>
2293
2294Instrument only functions from files where names don't match all the regexes separated by a semi-colon
2295
2296.. option:: -fprofile-filter-files=<arg>
2297
2298Instrument only functions from files where names match any regex separated by a semi-colon
2299
2300.. option:: -fprofile-generate, -fno-profile-generate
2301
2302Generate instrumented code to collect execution counts into default.profraw (overridden by LLVM\_PROFILE\_FILE env var)
2303
2304.. program:: clang1
2305.. option:: -fprofile-generate=<directory>
2306.. program:: clang
2307
2308Generate instrumented code to collect execution counts into <directory>/default.profraw (overridden by LLVM\_PROFILE\_FILE env var)
2309
2310.. option:: -fprofile-instr-generate, -fno-profile-instr-generate
2311
2312Generate instrumented code to collect execution counts into default.profraw file (overridden by '=' form of option or LLVM\_PROFILE\_FILE env var)
2313
2314.. program:: clang1
2315.. option:: -fprofile-instr-generate=<file>
2316.. program:: clang
2317
2318Generate instrumented code to collect execution counts into <file> (overridden by LLVM\_PROFILE\_FILE env var)
2319
2320.. option:: -fprofile-instr-use, -fno-profile-instr-use, -fprofile-use
2321
2322.. program:: clang1
2323.. option:: -fprofile-instr-use=<arg>
2324.. program:: clang
2325
2326Use instrumentation data for profile-guided optimization
2327
2328.. option:: -fprofile-list=<arg>
2329
2330Filename defining the list of functions/files to instrument
2331
2332.. option:: -fprofile-remapping-file=<file>
2333
2334Use the remappings described in <file> to match the profile data against names in the program
2335
2336.. option:: -fprofile-sample-accurate, -fauto-profile-accurate, -fno-profile-sample-accurate
2337
2338Specifies that the sample profile is accurate. If the sample
2339               profile is accurate, callsites without profile samples are marked
2340               as cold. Otherwise, treat callsites without profile samples as if
2341               we have no profile
2342
2343.. option:: -fprofile-sample-use, -fauto-profile, -fno-profile-sample-use
2344
2345.. program:: clang1
2346.. option:: -fprofile-sample-use=<arg>, -fauto-profile=<arg>
2347.. program:: clang
2348
2349Enable sample-based profile guided optimizations
2350
2351.. option:: -fprofile-update=<method>
2352
2353Set update method of profile counters. <method> must be 'atomic', 'prefer-atomic' or 'single'.
2354
2355.. program:: clang1
2356.. option:: -fprofile-use=<pathname>
2357.. program:: clang
2358
2359Use instrumentation data for profile-guided optimization. If pathname is a directory, it reads from <pathname>/default.profdata. Otherwise, it reads from file <pathname>.
2360
2361.. option:: -fprotect-parens, -fno-protect-parens
2362
2363Determines whether the optimizer honors parentheses when floating-point expressions are evaluated
2364
2365.. option:: -fpseudo-probe-for-profiling, -fno-pseudo-probe-for-profiling
2366
2367Emit pseudo probes for sample profiling
2368
2369.. option:: -freciprocal-math, -fno-reciprocal-math
2370
2371Allow division operations to be reassociated
2372
2373.. option:: -freg-struct-return
2374
2375Override the default ABI to return small structs in registers
2376
2377.. option:: -fregister-global-dtors-with-atexit, -fno-register-global-dtors-with-atexit
2378
2379Use atexit or \_\_cxa\_atexit to register global destructors
2380
2381.. option:: -frelaxed-template-template-args, -fno-relaxed-template-template-args
2382
2383Enable C++17 relaxed template template argument matching
2384
2385.. option:: -freroll-loops, -fno-reroll-loops
2386
2387Turn on loop reroller
2388
2389.. option:: -fretain-comments-from-system-headers
2390
2391.. option:: -frewrite-imports, -fno-rewrite-imports
2392
2393.. option:: -frewrite-includes, -fno-rewrite-includes
2394
2395.. option:: -frewrite-map-file=<arg>
2396
2397.. option:: -fropi, -fno-ropi
2398
2399Generate read-only position independent code (ARM only)
2400
2401.. option:: -frounding-math, -fno-rounding-math
2402
2403.. option:: -frtti, -fno-rtti
2404
2405.. option:: -frtti-data, -fno-rtti-data
2406
2407.. option:: -frwpi, -fno-rwpi
2408
2409Generate read-write position independent code (ARM only)
2410
2411.. option:: -fsanitize-memory-param-retval, -fno-sanitize-memory-param-retval
2412
2413Enable detection of uninitialized parameters and return values
2414
2415.. option:: -fsave-optimization-record, -fno-save-optimization-record
2416
2417Generate a YAML optimization record file
2418
2419.. program:: clang1
2420.. option:: -fsave-optimization-record=<format>
2421.. program:: clang
2422
2423Generate an optimization record file in a specific format
2424
2425.. option:: -fseh-exceptions
2426
2427Use SEH style exceptions
2428
2429.. option:: -fsemantic-interposition, -fno-semantic-interposition
2430
2431.. option:: -fshort-enums, -fno-short-enums
2432
2433Allocate to an enum type only as many bytes as it needs for the declared range of possible values
2434
2435.. option:: -fshort-wchar, -fno-short-wchar
2436
2437Force wchar\_t to be a short unsigned int
2438
2439.. option:: -fshow-column, -fno-show-column
2440
2441.. option:: -fshow-overloads=<arg>
2442
2443Which overload candidates to show when overload resolution fails. Defaults to 'all'. <arg> must be 'best' or 'all'.
2444
2445.. option:: -fshow-source-location, -fno-show-source-location
2446
2447.. option:: -fsignaling-math, -fno-signaling-math
2448
2449.. option:: -fsigned-bitfields
2450
2451.. option:: -fsigned-char, -fno-signed-char, --signed-char
2452
2453char is signed
2454
2455.. option:: -fsigned-zeros, -fno-signed-zeros
2456
2457.. option:: -fsized-deallocation, -fno-sized-deallocation
2458
2459Enable C++14 sized global deallocation functions
2460
2461.. option:: -fsjlj-exceptions
2462
2463Use SjLj style exceptions
2464
2465.. option:: -fslp-vectorize, -fno-slp-vectorize, -ftree-slp-vectorize
2466
2467Enable the superword-level parallelism vectorization passes
2468
2469.. option:: -fspell-checking, -fno-spell-checking
2470
2471.. option:: -fspell-checking-limit=<arg>
2472
2473.. option:: -fsplit-dwarf-inlining, -fno-split-dwarf-inlining
2474
2475Provide minimal debug info in the object/executable to facilitate online symbolication/stack traces in the absence of .dwo/.dwp files when using Split DWARF
2476
2477.. option:: -fsplit-lto-unit, -fno-split-lto-unit
2478
2479Enables splitting of the LTO unit
2480
2481.. option:: -fsplit-machine-functions, -fno-split-machine-functions
2482
2483Enable late function splitting using profile information (x86 ELF)
2484
2485.. option:: -fsplit-stack, -fno-split-stack
2486
2487Use segmented stack
2488
2489.. option:: -fstack-clash-protection, -fno-stack-clash-protection
2490
2491Enable stack clash protection
2492
2493.. option:: -fstack-protector, -fno-stack-protector
2494
2495Enable stack protectors for some functions vulnerable to stack smashing. This uses a loose heuristic which considers functions vulnerable if they contain a char (or 8bit integer) array or constant sized calls to alloca , which are of greater size than ssp-buffer-size (default: 8 bytes). All variable sized calls to alloca are considered vulnerable. A function with a stack protector has a guard value added to the stack frame that is checked on function exit. The guard value must be positioned in the stack frame such that a buffer overflow from a vulnerable variable will overwrite the guard value before overwriting the function's return address. The reference stack guard value is stored in a global variable.
2496
2497.. option:: -fstack-protector-all
2498
2499Enable stack protectors for all functions
2500
2501.. option:: -fstack-protector-strong
2502
2503Enable stack protectors for some functions vulnerable to stack smashing. Compared to -fstack-protector, this uses a stronger heuristic that includes functions containing arrays of any size (and any type), as well as any calls to alloca or the taking of an address from a local variable
2504
2505.. option:: -fstack-size-section, -fno-stack-size-section
2506
2507Emit section containing metadata on function stack sizes
2508
2509.. option:: -fstack-usage
2510
2511Emit .su file containing information on function stack sizes
2512
2513.. option:: -fstandalone-debug, -fno-limit-debug-info, -fno-standalone-debug
2514
2515Emit full debug info for all types used by the program
2516
2517.. option:: -fstrict-aliasing, -fno-strict-aliasing
2518
2519.. option:: -fstrict-enums, -fno-strict-enums
2520
2521Enable optimizations based on the strict definition of an enum's value range
2522
2523.. option:: -fstrict-float-cast-overflow, -fno-strict-float-cast-overflow
2524
2525Assume that overflowing float-to-int casts are undefined (default)
2526
2527.. option:: -fstrict-overflow, -fno-strict-overflow
2528
2529.. option:: -fstrict-return, -fno-strict-return
2530
2531.. option:: -fstrict-vtable-pointers, -fno-strict-vtable-pointers
2532
2533Enable optimizations based on the strict rules for overwriting polymorphic C++ objects
2534
2535.. option:: -fstruct-path-tbaa, -fno-struct-path-tbaa
2536
2537.. option:: -fswift-async-fp=<option>
2538
2539Control emission of Swift async extended frame info. <option> must be 'auto', 'always' or 'never'.
2540
2541.. option:: -fsymbol-partition=<arg>
2542
2543.. option:: -ftabstop=<arg>
2544
2545.. option:: -ftemplate-backtrace-limit=<arg>
2546
2547.. option:: -ftemplate-depth-<arg>
2548
2549.. option:: -ftemplate-depth=<arg>
2550
2551.. option:: -ftest-coverage, -fno-test-coverage
2552
2553.. option:: -fthin-link-bitcode=<arg>
2554
2555Write minimized bitcode to <file> for the ThinLTO thin link only
2556
2557.. option:: -fthinlto-index=<arg>
2558
2559Perform ThinLTO importing using provided function summary index
2560
2561.. option:: -fthreadsafe-statics, -fno-threadsafe-statics
2562
2563.. option:: -ftime-report
2564
2565.. program:: clang1
2566.. option:: -ftime-report=<arg>
2567.. program:: clang
2568
2569(For new pass manager) 'per-pass': one report for each pass; 'per-pass-run': one report for each pass invocation. <arg> must be 'per-pass' or 'per-pass-run'.
2570
2571.. option:: -ftime-trace
2572
2573
2574Turn on time profiler. Generates JSON file based on output filename. Results
2575can be analyzed with chrome://tracing or `Speedscope App
2576<https://www.speedscope.app>`_ for flamegraph visualization.
2577
2578.. option:: -ftime-trace-granularity=<arg>
2579
2580Minimum time granularity (in microseconds) traced by time profiler
2581
2582.. option:: -ftls-model=<arg>
2583
2584 <arg> must be 'global-dynamic', 'local-dynamic', 'initial-exec' or 'local-exec'.
2585
2586.. option:: -ftrap-function=<arg>
2587
2588Issue call to specified function rather than a trap instruction
2589
2590.. option:: -ftrapping-math, -fno-trapping-math
2591
2592.. option:: -ftrapv
2593
2594Trap on integer overflow
2595
2596.. option:: -ftrapv-handler <arg>
2597
2598.. program:: clang1
2599.. option:: -ftrapv-handler=<function name>
2600.. program:: clang
2601
2602Specify the function to be called on overflow
2603
2604.. option:: -ftrigraphs, -fno-trigraphs, -trigraphs, --trigraphs
2605
2606Process trigraph sequences
2607
2608.. option:: -ftrivial-auto-var-init-stop-after=<arg>
2609
2610Stop initializing trivial automatic stack variables after the specified number of instances
2611
2612.. option:: -ftrivial-auto-var-init=<arg>
2613
2614Initialize trivial automatic stack variables. Defaults to 'uninitialized'. <arg> must be 'uninitialized', 'zero' or 'pattern'.
2615
2616.. option:: -funique-basic-block-section-names, -fno-unique-basic-block-section-names
2617
2618Use unique names for basic block sections (ELF Only)
2619
2620.. option:: -funique-internal-linkage-names, -fno-unique-internal-linkage-names
2621
2622Uniqueify Internal Linkage Symbol Names by appending the MD5 hash of the module path
2623
2624.. option:: -funique-section-names, -fno-unique-section-names
2625
2626.. option:: -funroll-loops, -fno-unroll-loops
2627
2628Turn on loop unroller
2629
2630.. option:: -funsafe-math-optimizations, -fno-unsafe-math-optimizations
2631
2632.. option:: -funsigned-bitfields
2633
2634.. option:: -funsigned-char, -fno-unsigned-char, --unsigned-char
2635
2636.. option:: -funstable, -fno-unstable
2637
2638Enable unstable and experimental features
2639
2640.. option:: -funwind-tables, -fno-unwind-tables
2641
2642.. option:: -fuse-cxa-atexit, -fno-use-cxa-atexit
2643
2644.. option:: -fuse-init-array, -fno-use-init-array
2645
2646.. option:: -fuse-ld=<arg>
2647
2648.. option:: -fuse-line-directives, -fno-use-line-directives
2649
2650Use #line in preprocessed output
2651
2652.. option:: -fvalidate-ast-input-files-content
2653
2654Compute and store the hash of input files used to build an AST. Files with mismatching mtime's are considered valid if both contents is identical
2655
2656.. option:: -fveclib=<arg>
2657
2658Use the given vector functions library. <arg> must be 'Accelerate', 'libmvec', 'MASSV', 'SVML', 'Darwin_libsystem_m' or 'none'.
2659
2660.. option:: -fvectorize, -fno-vectorize, -ftree-vectorize
2661
2662Enable the loop vectorization passes
2663
2664.. option:: -fverbose-asm, -dA, -fno-verbose-asm
2665
2666Generate verbose assembly output
2667
2668.. option:: -fvirtual-function-elimination, -fno-virtual-function-elimination
2669
2670Enables dead virtual function elimination optimization. Requires -flto=full
2671
2672.. option:: -fvisibility-dllexport=<arg>
2673
2674The visibility for dllexport definitions \[-fvisibility-from-dllstorageclass\]. <arg> must be 'default', 'hidden', 'internal' or 'protected'.
2675
2676.. option:: -fvisibility-externs-dllimport=<arg>
2677
2678The visibility for dllimport external declarations \[-fvisibility-from-dllstorageclass\]. <arg> must be 'default', 'hidden', 'internal' or 'protected'.
2679
2680.. option:: -fvisibility-externs-nodllstorageclass=<arg>
2681
2682The visibility for external declarations without an explicit DLL dllstorageclass \[-fvisibility-from-dllstorageclass\]. <arg> must be 'default', 'hidden', 'internal' or 'protected'.
2683
2684.. option:: -fvisibility-from-dllstorageclass, -fno-visibility-from-dllstorageclass
2685
2686Set the visibility of symbols in the generated code from their DLL storage class
2687
2688.. option:: -fvisibility-global-new-delete-hidden
2689
2690Give global C++ operator new and delete declarations hidden visibility
2691
2692.. option:: -fvisibility-inlines-hidden, -fno-visibility-inlines-hidden
2693
2694Give inline C++ member functions hidden visibility by default
2695
2696.. option:: -fvisibility-inlines-hidden-static-local-var, -fno-visibility-inlines-hidden-static-local-var
2697
2698When -fvisibility-inlines-hidden is enabled, static variables in inline C++ member functions will also be given hidden visibility by default
2699
2700.. option:: -fvisibility-ms-compat
2701
2702Give global types 'default' visibility and global functions and variables 'hidden' visibility by default
2703
2704.. option:: -fvisibility-nodllstorageclass=<arg>
2705
2706The visibility for definitions without an explicit DLL export class \[-fvisibility-from-dllstorageclass\]. <arg> must be 'default', 'hidden', 'internal' or 'protected'.
2707
2708.. option:: -fvisibility=<arg>
2709
2710Set the default symbol visibility for all global declarations. <arg> must be 'hidden' or 'default'.
2711
2712.. option:: -fwasm-exceptions
2713
2714Use WebAssembly style exceptions
2715
2716.. option:: -fwhole-program-vtables, -fno-whole-program-vtables
2717
2718Enables whole-program vtable optimization. Requires -flto
2719
2720.. option:: -fwrapv, -fno-wrapv
2721
2722Treat signed integer overflow as two's complement
2723
2724.. option:: -fwritable-strings
2725
2726Store string literals as writable data
2727
2728.. option:: -fxl-pragma-pack, -fno-xl-pragma-pack
2729
2730Enable IBM XL #pragma pack handling
2731
2732.. option:: -fxray-always-emit-customevents, -fno-xray-always-emit-customevents
2733
2734Always emit \_\_xray\_customevent(...) calls even if the containing function is not always instrumented
2735
2736.. option:: -fxray-always-emit-typedevents, -fno-xray-always-emit-typedevents
2737
2738Always emit \_\_xray\_typedevent(...) calls even if the containing function is not always instrumented
2739
2740.. option:: -fxray-always-instrument=<arg>
2741
2742DEPRECATED: Filename defining the whitelist for imbuing the 'always instrument' XRay attribute.
2743
2744.. option:: -fxray-attr-list=<arg>
2745
2746Filename defining the list of functions/types for imbuing XRay attributes.
2747
2748.. option:: -fxray-function-groups=<arg>
2749
2750Only instrument 1 of N groups
2751
2752.. option:: -fxray-function-index, -fno-xray-function-index
2753
2754.. option:: -fxray-ignore-loops, -fno-xray-ignore-loops
2755
2756Don't instrument functions with loops unless they also meet the minimum function size
2757
2758.. option:: -fxray-instruction-threshold<arg>
2759
2760.. program:: clang1
2761.. option:: -fxray-instruction-threshold=<arg>
2762.. program:: clang
2763
2764Sets the minimum function size to instrument with XRay
2765
2766.. option:: -fxray-instrument, -fno-xray-instrument
2767
2768Generate XRay instrumentation sleds on function entry and exit
2769
2770.. option:: -fxray-instrumentation-bundle=<arg>
2771
2772Select which XRay instrumentation points to emit. Options: all, none, function-entry, function-exit, function, custom. Default is 'all'.  'function' includes both 'function-entry' and 'function-exit'.
2773
2774.. option:: -fxray-link-deps
2775
2776Tells clang to add the link dependencies for XRay.
2777
2778.. option:: -fxray-modes=<arg>
2779
2780List of modes to link in by default into XRay instrumented binaries.
2781
2782.. option:: -fxray-never-instrument=<arg>
2783
2784DEPRECATED: Filename defining the whitelist for imbuing the 'never instrument' XRay attribute.
2785
2786.. option:: -fxray-selected-function-group=<arg>
2787
2788When using -fxray-function-groups, select which group of functions to instrument. Valid range is 0 to fxray-function-groups - 1
2789
2790.. option:: -fzero-call-used-regs=<arg>
2791
2792Clear call-used registers upon function return (AArch64/x86 only). <arg> must be 'skip', 'used-gpr-arg', 'used-gpr', 'used-arg', 'used', 'all-gpr-arg', 'all-gpr', 'all-arg' or 'all'.
2793
2794.. option:: -fzero-initialized-in-bss, -fno-zero-initialized-in-bss
2795
2796.. option:: -fzvector, -fno-zvector, -mzvector
2797
2798Enable System z vector language extension
2799
2800.. option:: --gpu-bundle-output, --no-gpu-bundle-output
2801
2802Bundle output files of HIP device compilation
2803
2804.. option:: --offload-new-driver, --no-offload-new-driver
2805
2806Use the new driver for offloading compilation.
2807
2808.. option:: -pedantic, --pedantic, -no-pedantic, --no-pedantic
2809
2810Warn on language extensions
2811
2812.. option:: -pedantic-errors, --pedantic-errors
2813
2814OpenCL flags
2815------------
2816.. option:: -cl-denorms-are-zero
2817
2818OpenCL only. Allow denormals to be flushed to zero.
2819
2820.. option:: -cl-ext=<arg1>,<arg2>...
2821
2822OpenCL only. Enable or disable OpenCL extensions/optional features. The argument is a comma-separated sequence of one or more extension names, each prefixed by '+' or '-'.
2823
2824.. option:: -cl-fast-relaxed-math
2825
2826OpenCL only. Sets -cl-finite-math-only and -cl-unsafe-math-optimizations, and defines \_\_FAST\_RELAXED\_MATH\_\_.
2827
2828.. option:: -cl-finite-math-only
2829
2830OpenCL only. Allow floating-point optimizations that assume arguments and results are not NaNs or +-Inf.
2831
2832.. option:: -cl-fp32-correctly-rounded-divide-sqrt
2833
2834OpenCL only. Specify that single precision floating-point divide and sqrt used in the program source are correctly rounded.
2835
2836.. option:: -cl-kernel-arg-info
2837
2838OpenCL only. Generate kernel argument metadata.
2839
2840.. option:: -cl-mad-enable
2841
2842OpenCL only. Allow use of less precise MAD computations in the generated binary.
2843
2844.. option:: -cl-no-signed-zeros
2845
2846OpenCL only. Allow use of less precise no signed zeros computations in the generated binary.
2847
2848.. option:: -cl-no-stdinc
2849
2850OpenCL only. Disables all standard includes containing non-native compiler types and functions.
2851
2852.. option:: -cl-opt-disable
2853
2854OpenCL only. This option disables all optimizations. By default optimizations are enabled.
2855
2856.. option:: -cl-single-precision-constant
2857
2858OpenCL only. Treat double precision floating-point constant as single precision constant.
2859
2860.. option:: -cl-std=<arg>
2861
2862OpenCL language standard to compile for. <arg> must be 'cl', 'CL', 'cl1.0', 'CL1.0', 'cl1.1', 'CL1.1', 'cl1.2', 'CL1.2', 'cl2.0', 'CL2.0', 'cl3.0', 'CL3.0', 'clc++', 'CLC++', 'clc++1.0', 'CLC++1.0', 'clc++2021' or 'CLC++2021'.
2863
2864.. option:: -cl-strict-aliasing
2865
2866OpenCL only. This option is added for compatibility with OpenCL 1.0.
2867
2868.. option:: -cl-uniform-work-group-size
2869
2870OpenCL only. Defines that the global work-size be a multiple of the work-group size specified to clEnqueueNDRangeKernel
2871
2872.. option:: -cl-unsafe-math-optimizations
2873
2874OpenCL only. Allow unsafe floating-point optimizations.  Also implies -cl-no-signed-zeros and -cl-mad-enable.
2875
2876SYCL flags
2877----------
2878.. option:: -fsycl, -fno-sycl
2879
2880Enables SYCL kernels compilation for device
2881
2882.. option:: -sycl-std=<arg>
2883
2884SYCL language standard to compile for. <arg> must be '2020', '2017', '121', '1.2.1' or 'sycl-1.2.1'.
2885
2886Target-dependent compilation options
2887~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2888.. option:: -G<size>, -G=<arg>, -msmall-data-limit=<arg>, -msmall-data-threshold=<arg>
2889
2890Put objects of at most <size> bytes into small data section (MIPS / Hexagon)
2891
2892.. option:: -ffixed-x1
2893
2894Reserve the x1 register (AArch64/RISC-V only)
2895
2896.. option:: -ffixed-x10
2897
2898Reserve the x10 register (AArch64/RISC-V only)
2899
2900.. option:: -ffixed-x11
2901
2902Reserve the x11 register (AArch64/RISC-V only)
2903
2904.. option:: -ffixed-x12
2905
2906Reserve the x12 register (AArch64/RISC-V only)
2907
2908.. option:: -ffixed-x13
2909
2910Reserve the x13 register (AArch64/RISC-V only)
2911
2912.. option:: -ffixed-x14
2913
2914Reserve the x14 register (AArch64/RISC-V only)
2915
2916.. option:: -ffixed-x15
2917
2918Reserve the x15 register (AArch64/RISC-V only)
2919
2920.. option:: -ffixed-x16
2921
2922Reserve the x16 register (AArch64/RISC-V only)
2923
2924.. option:: -ffixed-x17
2925
2926Reserve the x17 register (AArch64/RISC-V only)
2927
2928.. option:: -ffixed-x18
2929
2930Reserve the x18 register (AArch64/RISC-V only)
2931
2932.. option:: -ffixed-x19
2933
2934Reserve the x19 register (AArch64/RISC-V only)
2935
2936.. option:: -ffixed-x2
2937
2938Reserve the x2 register (AArch64/RISC-V only)
2939
2940.. option:: -ffixed-x20
2941
2942Reserve the x20 register (AArch64/RISC-V only)
2943
2944.. option:: -ffixed-x21
2945
2946Reserve the x21 register (AArch64/RISC-V only)
2947
2948.. option:: -ffixed-x22
2949
2950Reserve the x22 register (AArch64/RISC-V only)
2951
2952.. option:: -ffixed-x23
2953
2954Reserve the x23 register (AArch64/RISC-V only)
2955
2956.. option:: -ffixed-x24
2957
2958Reserve the x24 register (AArch64/RISC-V only)
2959
2960.. option:: -ffixed-x25
2961
2962Reserve the x25 register (AArch64/RISC-V only)
2963
2964.. option:: -ffixed-x26
2965
2966Reserve the x26 register (AArch64/RISC-V only)
2967
2968.. option:: -ffixed-x27
2969
2970Reserve the x27 register (AArch64/RISC-V only)
2971
2972.. option:: -ffixed-x28
2973
2974Reserve the x28 register (AArch64/RISC-V only)
2975
2976.. option:: -ffixed-x29
2977
2978Reserve the x29 register (AArch64/RISC-V only)
2979
2980.. option:: -ffixed-x3
2981
2982Reserve the x3 register (AArch64/RISC-V only)
2983
2984.. option:: -ffixed-x30
2985
2986Reserve the x30 register (AArch64/RISC-V only)
2987
2988.. option:: -ffixed-x31
2989
2990Reserve the x31 register (AArch64/RISC-V only)
2991
2992.. option:: -ffixed-x4
2993
2994Reserve the x4 register (AArch64/RISC-V only)
2995
2996.. option:: -ffixed-x5
2997
2998Reserve the x5 register (AArch64/RISC-V only)
2999
3000.. option:: -ffixed-x6
3001
3002Reserve the x6 register (AArch64/RISC-V only)
3003
3004.. option:: -ffixed-x7
3005
3006Reserve the x7 register (AArch64/RISC-V only)
3007
3008.. option:: -ffixed-x8
3009
3010Reserve the x8 register (AArch64/RISC-V only)
3011
3012.. option:: -ffixed-x9
3013
3014Reserve the x9 register (AArch64/RISC-V only)
3015
3016.. option:: -ffuchsia-api-level=<arg>
3017
3018Set Fuchsia API level
3019
3020.. option:: -inline-asm=<arg>
3021
3022 <arg> must be 'att' or 'intel'.
3023
3024.. option:: -m16
3025
3026.. option:: -m32
3027
3028.. option:: -m64
3029
3030.. option:: -mabi=<arg>
3031
3032.. program:: clang1
3033.. option:: -mabi=vec-default
3034.. program:: clang
3035
3036Enable the default Altivec ABI on AIX (AIX only). Uses only volatile vector registers.
3037
3038.. program:: clang2
3039.. option:: -mabi=vec-extabi
3040.. program:: clang
3041
3042Enable the extended Altivec ABI on AIX (AIX only). Uses volatile and nonvolatile vector registers
3043
3044.. option:: -maix-struct-return
3045
3046Return all structs in memory (PPC32 only)
3047
3048.. option:: -malign-branch-boundary=<arg>
3049
3050Specify the boundary's size to align branches
3051
3052.. option:: -malign-branch=<arg1>,<arg2>...
3053
3054Specify types of branches to align
3055
3056.. option:: -malign-double
3057
3058Align doubles to two words in structs (x86 only)
3059
3060.. option:: -mamdgpu-ieee, -mno-amdgpu-ieee
3061
3062Sets the IEEE bit in the expected default floating point  mode register. Floating point opcodes that support exception flag gathering quiet and propagate signaling NaN inputs per IEEE 754-2008. This option changes the ABI. (AMDGPU only)
3063
3064.. option:: -march=<arg>
3065
3066.. option:: -masm=<arg>
3067
3068.. option:: -mbackchain, -mno-backchain
3069
3070Link stack frames through backchain on System Z
3071
3072.. option:: -mbranch-protection=<arg>
3073
3074Enforce targets of indirect branches and function returns
3075
3076.. option:: -mbranches-within-32B-boundaries
3077
3078Align selected branches (fused, jcc, jmp) within 32-byte boundary
3079
3080.. option:: -mcmodel=<arg>, -mcmodel=medany (equivalent to -mcmodel=medium), -mcmodel=medlow (equivalent to -mcmodel=small)
3081
3082.. option:: -mcode-object-v3, -mno-code-object-v3
3083
3084Legacy option to specify code object ABI V3 (AMDGPU only)
3085
3086.. option:: -mcode-object-version=<arg>
3087
3088Specify code object ABI version. Defaults to 4. (AMDGPU only). <arg> must be 'none', '2', '3', '4' or '5'.
3089
3090.. option:: -mconsole<arg>
3091
3092.. program:: clang1
3093.. option:: -mcpu=<arg>, -mv5 (equivalent to -mcpu=hexagonv5), -mv55 (equivalent to -mcpu=hexagonv55), -mv60 (equivalent to -mcpu=hexagonv60), -mv62 (equivalent to -mcpu=hexagonv62), -mv65 (equivalent to -mcpu=hexagonv65), -mv66 (equivalent to -mcpu=hexagonv66), -mv67 (equivalent to -mcpu=hexagonv67), -mv67t (equivalent to -mcpu=hexagonv67t), -mv68 (equivalent to -mcpu=hexagonv68), -mv69 (equivalent to -mcpu=hexagonv69)
3094.. program:: clang
3095
3096.. option:: -mcrc, -mno-crc
3097
3098Allow use of CRC instructions (ARM/Mips only)
3099
3100.. option:: -mdefault-build-attributes<arg>, -mno-default-build-attributes<arg>
3101
3102.. option:: -mdefault-visibility-export-mapping=<arg>
3103
3104Mapping between default visibility and export. <arg> must be 'none', 'explicit' or 'all'.
3105
3106.. option:: -mdll<arg>
3107
3108.. option:: -mdouble=<n
3109
3110Force double to be <n> bits. <n must be '32' or '64'.
3111
3112.. option:: -mdynamic-no-pic<arg>
3113
3114.. option:: -meabi <arg>
3115
3116Set EABI type. Default depends on triple). <arg> must be 'default', '4', '5' or 'gnu'.
3117
3118.. option:: -menable-experimental-extensions
3119
3120Enable use of experimental RISC-V extensions.
3121
3122.. option:: -mfentry
3123
3124Insert calls to fentry at function entry (x86/SystemZ only)
3125
3126.. option:: -mfloat-abi=<arg>
3127
3128 <arg> must be 'soft', 'softfp' or 'hard'.
3129
3130.. option:: -mfpmath=<arg>
3131
3132.. option:: -mfpu=<arg>
3133
3134.. option:: -mgeneral-regs-only
3135
3136Generate code which only uses the general purpose registers (AArch64/x86 only)
3137
3138.. option:: -mglobal-merge, -mno-global-merge
3139
3140Enable merging of globals
3141
3142.. option:: -mhard-float
3143
3144.. option:: -mhwdiv=<arg>, --mhwdiv <arg>, --mhwdiv=<arg>
3145
3146.. option:: -mhwmult=<arg>
3147
3148.. option:: -miamcu, -mno-iamcu
3149
3150Use Intel MCU ABI
3151
3152.. option:: -mibt-seal
3153
3154Optimize fcf-protection=branch/full (requires LTO).
3155
3156.. option:: -mignore-xcoff-visibility
3157
3158Not emit the visibility attribute for asm in AIX OS or give all symbols 'unspecified' visibility in XCOFF object file
3159
3160.. option:: -mimplicit-float, -mno-implicit-float
3161
3162.. option:: -mimplicit-it=<arg>
3163
3164.. option:: -mincremental-linker-compatible, -mno-incremental-linker-compatible
3165
3166(integrated-as) Emit an object file which can be used with an incremental linker
3167
3168.. option:: -miphoneos-version-min=<arg>, -mios-version-min=<arg>
3169
3170.. option:: -mkernel
3171
3172.. option:: -mlong-calls, -mno-long-calls
3173
3174Generate branches with extended addressability, usually via indirect jumps.
3175
3176.. option:: -mlvi-cfi, -mno-lvi-cfi
3177
3178Enable only control-flow mitigations for Load Value Injection (LVI)
3179
3180.. option:: -mlvi-hardening, -mno-lvi-hardening
3181
3182Enable all mitigations for Load Value Injection (LVI)
3183
3184.. option:: -mmacosx-version-min=<arg>, -mmacos-version-min=<arg>
3185
3186Set Mac OS X deployment target
3187
3188.. option:: -mmcu=<arg>
3189
3190.. option:: -mms-bitfields, -mno-ms-bitfields
3191
3192Set the default structure layout to be compatible with the Microsoft compiler standard
3193
3194.. option:: -mnop-mcount
3195
3196Generate mcount/\_\_fentry\_\_ calls as nops. To activate they need to be patched in.
3197
3198.. option:: -momit-leaf-frame-pointer, -mno-omit-leaf-frame-pointer
3199
3200Omit frame pointer setup for leaf functions
3201
3202.. option:: -moslib=<arg>
3203
3204.. option:: -mpacked-stack, -mno-packed-stack
3205
3206Use packed stack layout (SystemZ only).
3207
3208.. option:: -mpad-max-prefix-size=<arg>
3209
3210Specify maximum number of prefixes to use for padding
3211
3212.. option:: -mprefer-vector-width=<arg>
3213
3214Specifies preferred vector width for auto-vectorization. Defaults to 'none' which allows target specific decisions.
3215
3216.. option:: -mqdsp6-compat
3217
3218Enable hexagon-qdsp6 backward compatibility
3219
3220.. option:: -mrecip
3221
3222.. program:: clang1
3223.. option:: -mrecip=<arg1>,<arg2>...
3224.. program:: clang
3225
3226.. option:: -mrecord-mcount
3227
3228Generate a \_\_mcount\_loc section entry for each \_\_fentry\_\_ call.
3229
3230.. option:: -mred-zone, -mno-red-zone
3231
3232.. option:: -mregparm=<arg>
3233
3234.. option:: -mrelax, -mno-relax
3235
3236Enable linker relaxation
3237
3238.. option:: -mrelax-all, -mno-relax-all
3239
3240(integrated-as) Relax all machine instructions
3241
3242.. option:: -mretpoline, -mno-retpoline
3243
3244.. option:: -mrtd, -mno-rtd
3245
3246Make StdCall calling convention the default
3247
3248.. option:: -mseses, -mno-seses
3249
3250Enable speculative execution side effect suppression (SESES). Includes LVI control flow integrity mitigations
3251
3252.. option:: -msign-return-address=<arg>
3253
3254Select return address signing scope. <arg> must be 'none', 'all' or 'non-leaf'.
3255
3256.. option:: -msim
3257
3258.. option:: -mskip-rax-setup, -mno-skip-rax-setup
3259
3260Skip setting up RAX register when passing variable arguments (x86 only)
3261
3262.. option:: -msoft-float, -mno-soft-float
3263
3264Use software floating point
3265
3266.. option:: -mspeculative-load-hardening, -mno-speculative-load-hardening
3267
3268.. option:: -mstack-alignment=<arg>
3269
3270Set the stack alignment
3271
3272.. option:: -mstack-arg-probe, -mno-stack-arg-probe
3273
3274Enable stack probes
3275
3276.. option:: -mstack-probe-size=<arg>
3277
3278Set the stack probe size
3279
3280.. option:: -mstack-protector-guard-offset=<arg>
3281
3282Use the given offset for addressing the stack-protector guard
3283
3284.. option:: -mstack-protector-guard-reg=<arg>
3285
3286Use the given reg for addressing the stack-protector guard
3287
3288.. option:: -mstack-protector-guard=<arg>
3289
3290Use the given guard (global, tls) for addressing the stack-protector guard
3291
3292.. option:: -mstackrealign, -mno-stackrealign
3293
3294Force realign the stack at entry to every function
3295
3296.. option:: -msvr4-struct-return
3297
3298Return small structs in registers (PPC32 only)
3299
3300.. option:: -mtargetos=<arg>
3301
3302Set the deployment target to be the specified OS and OS version
3303
3304.. option:: -mthread-model <arg>
3305
3306The thread model to use. Defaults to 'posix'). <arg> must be 'posix' or 'single'.
3307
3308.. option:: -mthreads<arg>
3309
3310.. option:: -mthumb, -mno-thumb
3311
3312.. option:: -mtls-direct-seg-refs, -mno-tls-direct-seg-refs
3313
3314Enable direct TLS access through segment registers (default)
3315
3316.. option:: -mtls-size=<arg>
3317
3318Specify bit size of immediate TLS offsets (AArch64 ELF only): 12 (for 4KB) \| 24 (for 16MB, default) \| 32 (for 4GB) \| 48 (for 256TB, needs -mcmodel=large)
3319
3320.. program:: clang1
3321.. option:: -mtune=<arg>
3322.. program:: clang
3323
3324Only supported on X86 and RISC-V. Otherwise accepted for compatibility with GCC.
3325
3326.. option:: -mtvos-version-min=<arg>, -mappletvos-version-min=<arg>
3327
3328.. option:: -municode<arg>
3329
3330.. option:: -munsafe-fp-atomics, -mno-unsafe-fp-atomics
3331
3332Enable unsafe floating point atomic instructions (AMDGPU only)
3333
3334.. option:: -mvx, -mno-vx
3335
3336.. option:: -mwarn-nonportable-cfstrings, -mno-warn-nonportable-cfstrings
3337
3338.. option:: -mwatchos-version-min=<arg>
3339
3340.. option:: -mwavefrontsize64, -mno-wavefrontsize64
3341
3342Specify wavefront size 64 mode (AMDGPU only)
3343
3344.. option:: -mwindows<arg>
3345
3346.. option:: -mx32
3347
3348AARCH64
3349-------
3350.. option:: -fcall-saved-x10
3351
3352Make the x10 register call-saved (AArch64 only)
3353
3354.. option:: -fcall-saved-x11
3355
3356Make the x11 register call-saved (AArch64 only)
3357
3358.. option:: -fcall-saved-x12
3359
3360Make the x12 register call-saved (AArch64 only)
3361
3362.. option:: -fcall-saved-x13
3363
3364Make the x13 register call-saved (AArch64 only)
3365
3366.. option:: -fcall-saved-x14
3367
3368Make the x14 register call-saved (AArch64 only)
3369
3370.. option:: -fcall-saved-x15
3371
3372Make the x15 register call-saved (AArch64 only)
3373
3374.. option:: -fcall-saved-x18
3375
3376Make the x18 register call-saved (AArch64 only)
3377
3378.. option:: -fcall-saved-x8
3379
3380Make the x8 register call-saved (AArch64 only)
3381
3382.. option:: -fcall-saved-x9
3383
3384Make the x9 register call-saved (AArch64 only)
3385
3386.. option:: -mfix-cortex-a53-835769, -mno-fix-cortex-a53-835769
3387
3388Workaround Cortex-A53 erratum 835769 (AArch64 only)
3389
3390.. option:: -mmark-bti-property
3391
3392Add .note.gnu.property with BTI to assembly files (AArch64 only)
3393
3394.. option:: -msve-vector-bits=<arg>
3395
3396Specify the size in bits of an SVE vector register. Defaults to the vector length agnostic value of "scalable". (AArch64 only)
3397
3398.. option:: -mvscale-max=<arg>
3399
3400Specify the vscale maximum. Defaults to the vector length agnostic value of "0". (AArch64 only)
3401
3402.. option:: -mvscale-min=<arg>
3403
3404Specify the vscale minimum. Defaults to "1". (AArch64 only)
3405
3406AMDGPU
3407------
3408.. option:: -mcumode, -mno-cumode
3409
3410Specify CU wavefront execution mode (AMDGPU only)
3411
3412.. option:: -mtgsplit, -mno-tgsplit
3413
3414Enable threadgroup split execution mode (AMDGPU only)
3415
3416ARM
3417---
3418.. option:: -faapcs-bitfield-load
3419
3420Follows the AAPCS standard that all volatile bit-field write generates at least one load. (ARM only).
3421
3422.. option:: -faapcs-bitfield-width, -fno-aapcs-bitfield-width
3423
3424Follow the AAPCS standard requirement stating that volatile bit-field width is dictated by the field container type. (ARM only).
3425
3426.. option:: -ffixed-r9
3427
3428Reserve the r9 register (ARM only)
3429
3430.. option:: -mcmse
3431
3432Allow use of CMSE (Armv8-M Security Extensions)
3433
3434.. option:: -mexecute-only, -mno-execute-only, -mpure-code
3435
3436Disallow generation of data access to code sections (ARM only)
3437
3438.. option:: -mfix-cmse-cve-2021-35465, -mno-fix-cmse-cve-2021-35465
3439
3440Work around VLLDM erratum CVE-2021-35465 (ARM only)
3441
3442.. option:: -mfix-cortex-a57-aes-1742098, -mfix-cortex-a72-aes-1655431, -mno-fix-cortex-a57-aes-1742098
3443
3444Work around Cortex-A57 Erratum 1742098 (ARM only)
3445
3446.. option:: -mframe-chain=<arg>
3447
3448Select the frame chain model used to emit frame records (Arm only). <arg> must be 'none', 'aapcs' or 'aapcs+leaf'.
3449
3450.. option:: -mno-bti-at-return-twice
3451
3452Do not add a BTI instruction after a setjmp or other return-twice construct (Arm/AArch64 only)
3453
3454.. option:: -mno-movt
3455
3456Disallow use of movt/movw pairs (ARM only)
3457
3458.. option:: -mno-neg-immediates
3459
3460Disallow converting instructions with negative immediates to their negation or inversion.
3461
3462.. option:: -mnocrc
3463
3464Disallow use of CRC instructions (ARM only)
3465
3466.. option:: -mrestrict-it, -mno-restrict-it
3467
3468Disallow generation of complex IT blocks.
3469
3470.. option:: -mtp=<arg>
3471
3472Thread pointer access method (AArch32/AArch64 only). <arg> must be 'soft', 'cp15', 'el0', 'el1', 'el2' or 'el3'.
3473
3474.. option:: -munaligned-access, -mno-unaligned-access
3475
3476Allow memory accesses to be unaligned (AArch32/AArch64 only)
3477
3478Hexagon
3479-------
3480.. option:: -mhvx-ieee-fp, -mno-hvx-ieee-fp
3481
3482Enable Hexagon HVX IEEE floating-point
3483
3484.. option:: -mieee-rnd-near
3485
3486.. option:: -mmemops, -mno-memops
3487
3488Enable generation of memop instructions
3489
3490.. option:: -mnvj, -mno-nvj
3491
3492Enable generation of new-value jumps
3493
3494.. option:: -mnvs, -mno-nvs
3495
3496Enable generation of new-value stores
3497
3498.. option:: -mpackets, -mno-packets
3499
3500Enable generation of instruction packets
3501
3502Hexagon
3503-------
3504.. option:: -mhvx, -mno-hvx
3505
3506Enable Hexagon Vector eXtensions
3507
3508.. option:: -mhvx-length=<arg>
3509
3510Set Hexagon Vector Length. <arg> must be '64B' or '128B'.
3511
3512.. option:: -mhvx-qfloat, -mno-hvx-qfloat
3513
3514Enable Hexagon HVX QFloat instructions
3515
3516.. program:: clang1
3517.. option:: -mhvx=<arg>
3518.. program:: clang
3519
3520Enable Hexagon Vector eXtensions
3521
3522M68k
3523----
3524.. option:: -ffixed-a0
3525
3526Reserve the a0 register (M68k only)
3527
3528.. option:: -ffixed-a1
3529
3530Reserve the a1 register (M68k only)
3531
3532.. option:: -ffixed-a2
3533
3534Reserve the a2 register (M68k only)
3535
3536.. option:: -ffixed-a3
3537
3538Reserve the a3 register (M68k only)
3539
3540.. option:: -ffixed-a4
3541
3542Reserve the a4 register (M68k only)
3543
3544.. option:: -ffixed-a5
3545
3546Reserve the a5 register (M68k only)
3547
3548.. option:: -ffixed-a6
3549
3550Reserve the a6 register (M68k only)
3551
3552.. option:: -ffixed-d0
3553
3554Reserve the d0 register (M68k only)
3555
3556.. option:: -ffixed-d1
3557
3558Reserve the d1 register (M68k only)
3559
3560.. option:: -ffixed-d2
3561
3562Reserve the d2 register (M68k only)
3563
3564.. option:: -ffixed-d3
3565
3566Reserve the d3 register (M68k only)
3567
3568.. option:: -ffixed-d4
3569
3570Reserve the d4 register (M68k only)
3571
3572.. option:: -ffixed-d5
3573
3574Reserve the d5 register (M68k only)
3575
3576.. option:: -ffixed-d6
3577
3578Reserve the d6 register (M68k only)
3579
3580.. option:: -ffixed-d7
3581
3582Reserve the d7 register (M68k only)
3583
3584.. option:: -m68000
3585
3586.. option:: -m68010
3587
3588.. option:: -m68020
3589
3590.. option:: -m68030
3591
3592.. option:: -m68040
3593
3594.. option:: -m68060
3595
3596MIPS
3597----
3598.. option:: -mabicalls, -mno-abicalls
3599
3600Enable SVR4-style position-independent code (Mips only)
3601
3602.. option:: -mabs=<arg>
3603
3604.. option:: -mcheck-zero-division, -mno-check-zero-division
3605
3606.. option:: -mcompact-branches=<arg>
3607
3608.. option:: -mdouble-float
3609
3610.. option:: -mdsp, -mno-dsp
3611
3612.. option:: -mdspr2, -mno-dspr2
3613
3614.. option:: -membedded-data, -mno-embedded-data
3615
3616Place constants in the .rodata section instead of the .sdata section even if they meet the -G <size> threshold (MIPS)
3617
3618.. option:: -mextern-sdata, -mno-extern-sdata
3619
3620Assume that externally defined data is in the small data if it meets the -G <size> threshold (MIPS)
3621
3622.. option:: -mfix4300
3623
3624.. option:: -mfp32
3625
3626Use 32-bit floating point registers (MIPS only)
3627
3628.. option:: -mfp64
3629
3630Use 64-bit floating point registers (MIPS only)
3631
3632.. option:: -mginv, -mno-ginv
3633
3634.. option:: -mgpopt, -mno-gpopt
3635
3636Use GP relative accesses for symbols known to be in a small data section (MIPS)
3637
3638.. option:: -mindirect-jump=<arg>
3639
3640Change indirect jump instructions to inhibit speculation
3641
3642.. option:: -mips16
3643
3644.. option:: -mldc1-sdc1, -mno-ldc1-sdc1
3645
3646.. option:: -mlocal-sdata, -mno-local-sdata
3647
3648Extend the -G behaviour to object local data (MIPS)
3649
3650.. option:: -mmadd4, -mno-madd4
3651
3652Enable the generation of 4-operand madd.s, madd.d and related instructions.
3653
3654.. option:: -mmicromips, -mno-micromips
3655
3656.. option:: -mmsa, -mno-msa
3657
3658Enable MSA ASE (MIPS only)
3659
3660.. option:: -mmt, -mno-mt
3661
3662Enable MT ASE (MIPS only)
3663
3664.. option:: -mnan=<arg>
3665
3666.. option:: -mno-mips16
3667
3668.. option:: -msingle-float
3669
3670.. option:: -mvirt, -mno-virt
3671
3672.. option:: -mxgot, -mno-xgot
3673
3674PowerPC
3675-------
3676.. option:: -maltivec, -mno-altivec
3677
3678.. option:: -mcmpb, -mno-cmpb
3679
3680.. option:: -mcrbits, -mno-crbits
3681
3682.. option:: -mcrypto, -mno-crypto
3683
3684.. option:: -mdirect-move, -mno-direct-move
3685
3686.. option:: -mefpu2
3687
3688.. option:: -mfloat128, -mno-float128
3689
3690.. option:: -mfprnd, -mno-fprnd
3691
3692.. option:: -mhtm, -mno-htm
3693
3694.. option:: -minvariant-function-descriptors, -mno-invariant-function-descriptors
3695
3696.. option:: -misel, -mno-isel
3697
3698.. option:: -mlongcall, -mno-longcall
3699
3700.. option:: -mmfocrf, -mmfcrf, -mno-mfocrf
3701
3702.. option:: -mmma, -mno-mma
3703
3704.. option:: -mpaired-vector-memops, -mno-paired-vector-memops
3705
3706.. option:: -mpcrel, -mno-pcrel
3707
3708.. option:: -mpopcntd, -mno-popcntd
3709
3710.. option:: -mpower10-vector, -mno-power10-vector
3711
3712.. option:: -mpower8-vector, -mno-power8-vector
3713
3714.. option:: -mpower9-vector, -mno-power9-vector
3715
3716.. option:: -mprefixed, -mno-prefixed
3717
3718.. option:: -mprivileged
3719
3720.. option:: -mrop-protect
3721
3722.. option:: -msecure-plt
3723
3724.. option:: -mspe, -mno-spe
3725
3726.. option:: -mvsx, -mno-vsx
3727
3728WebAssembly
3729-----------
3730.. option:: -matomics, -mno-atomics
3731
3732.. option:: -mbulk-memory, -mno-bulk-memory
3733
3734.. option:: -mexception-handling, -mno-exception-handling
3735
3736.. option:: -mextended-const, -mno-extended-const
3737
3738.. option:: -mmultivalue, -mno-multivalue
3739
3740.. option:: -mmutable-globals, -mno-mutable-globals
3741
3742.. option:: -mnontrapping-fptoint, -mno-nontrapping-fptoint
3743
3744.. option:: -mreference-types, -mno-reference-types
3745
3746.. option:: -mrelaxed-simd, -mno-relaxed-simd
3747
3748.. option:: -msign-ext, -mno-sign-ext
3749
3750.. option:: -msimd128, -mno-simd128
3751
3752.. option:: -mtail-call, -mno-tail-call
3753
3754WebAssembly Driver
3755------------------
3756.. option:: -mexec-model=<arg>
3757
3758Execution model (WebAssembly only). <arg> must be 'command' or 'reactor'.
3759
3760X86
3761---
3762.. option:: -m3dnow, -mno-3dnow
3763
3764.. option:: -m3dnowa, -mno-3dnowa
3765
3766.. option:: -madx, -mno-adx
3767
3768.. option:: -maes, -mno-aes
3769
3770.. option:: -mamx-bf16, -mno-amx-bf16
3771
3772.. option:: -mamx-int8, -mno-amx-int8
3773
3774.. option:: -mamx-tile, -mno-amx-tile
3775
3776.. option:: -mavx, -mno-avx
3777
3778.. option:: -mavx2, -mno-avx2
3779
3780.. option:: -mavx512bf16, -mno-avx512bf16
3781
3782.. option:: -mavx512bitalg, -mno-avx512bitalg
3783
3784.. option:: -mavx512bw, -mno-avx512bw
3785
3786.. option:: -mavx512cd, -mno-avx512cd
3787
3788.. option:: -mavx512dq, -mno-avx512dq
3789
3790.. option:: -mavx512er, -mno-avx512er
3791
3792.. option:: -mavx512f, -mno-avx512f
3793
3794.. option:: -mavx512fp16, -mno-avx512fp16
3795
3796.. option:: -mavx512ifma, -mno-avx512ifma
3797
3798.. option:: -mavx512pf, -mno-avx512pf
3799
3800.. option:: -mavx512vbmi, -mno-avx512vbmi
3801
3802.. option:: -mavx512vbmi2, -mno-avx512vbmi2
3803
3804.. option:: -mavx512vl, -mno-avx512vl
3805
3806.. option:: -mavx512vnni, -mno-avx512vnni
3807
3808.. option:: -mavx512vp2intersect, -mno-avx512vp2intersect
3809
3810.. option:: -mavx512vpopcntdq, -mno-avx512vpopcntdq
3811
3812.. option:: -mavxvnni, -mno-avxvnni
3813
3814.. option:: -mbmi, -mno-bmi
3815
3816.. option:: -mbmi2, -mno-bmi2
3817
3818.. option:: -mcldemote, -mno-cldemote
3819
3820.. option:: -mclflushopt, -mno-clflushopt
3821
3822.. option:: -mclwb, -mno-clwb
3823
3824.. option:: -mclzero, -mno-clzero
3825
3826.. option:: -mcrc32, -mno-crc32
3827
3828.. option:: -mcx16, -mno-cx16
3829
3830.. option:: -menqcmd, -mno-enqcmd
3831
3832.. option:: -mf16c, -mno-f16c
3833
3834.. option:: -mfma, -mno-fma
3835
3836.. option:: -mfma4, -mno-fma4
3837
3838.. option:: -mfsgsbase, -mno-fsgsbase
3839
3840.. option:: -mfxsr, -mno-fxsr
3841
3842.. option:: -mgfni, -mno-gfni
3843
3844.. option:: -mhreset, -mno-hreset
3845
3846.. option:: -minvpcid, -mno-invpcid
3847
3848.. option:: -mkl, -mno-kl
3849
3850.. option:: -mlwp, -mno-lwp
3851
3852.. option:: -mlzcnt, -mno-lzcnt
3853
3854.. option:: -mmmx, -mno-mmx
3855
3856.. option:: -mmovbe, -mno-movbe
3857
3858.. option:: -mmovdir64b, -mno-movdir64b
3859
3860.. option:: -mmovdiri, -mno-movdiri
3861
3862.. option:: -mmwaitx, -mno-mwaitx
3863
3864.. option:: -mpclmul, -mno-pclmul
3865
3866.. option:: -mpconfig, -mno-pconfig
3867
3868.. option:: -mpku, -mno-pku
3869
3870.. option:: -mpopcnt, -mno-popcnt
3871
3872.. option:: -mprefetchwt1, -mno-prefetchwt1
3873
3874.. option:: -mprfchw, -mno-prfchw
3875
3876.. option:: -mptwrite, -mno-ptwrite
3877
3878.. option:: -mrdpid, -mno-rdpid
3879
3880.. option:: -mrdpru, -mno-rdpru
3881
3882.. option:: -mrdrnd, -mno-rdrnd
3883
3884.. option:: -mrdseed, -mno-rdseed
3885
3886.. option:: -mretpoline-external-thunk, -mno-retpoline-external-thunk
3887
3888.. option:: -mrtm, -mno-rtm
3889
3890.. option:: -msahf, -mno-sahf
3891
3892.. option:: -mserialize, -mno-serialize
3893
3894.. option:: -msgx, -mno-sgx
3895
3896.. option:: -msha, -mno-sha
3897
3898.. option:: -mshstk, -mno-shstk
3899
3900.. option:: -msse, -mno-sse
3901
3902.. option:: -msse2, -mno-sse2
3903
3904.. option:: -msse3, -mno-sse3
3905
3906.. option:: -msse4.1, -mno-sse4.1
3907
3908.. program:: clang1
3909.. option:: -msse4.2, -mno-sse4.2, -msse4
3910.. program:: clang
3911
3912.. option:: -msse4a, -mno-sse4a
3913
3914.. option:: -mssse3, -mno-ssse3
3915
3916.. option:: -mtbm, -mno-tbm
3917
3918.. option:: -mtsxldtrk, -mno-tsxldtrk
3919
3920.. option:: -muintr, -mno-uintr
3921
3922.. option:: -mvaes, -mno-vaes
3923
3924.. option:: -mvpclmulqdq, -mno-vpclmulqdq
3925
3926.. option:: -mvzeroupper, -mno-vzeroupper
3927
3928.. option:: -mwaitpkg, -mno-waitpkg
3929
3930.. option:: -mwbnoinvd, -mno-wbnoinvd
3931
3932.. option:: -mwidekl, -mno-widekl
3933
3934.. option:: -mx87, -m80387, -mno-x87
3935
3936.. option:: -mxop, -mno-xop
3937
3938.. option:: -mxsave, -mno-xsave
3939
3940.. option:: -mxsavec, -mno-xsavec
3941
3942.. option:: -mxsaveopt, -mno-xsaveopt
3943
3944.. option:: -mxsaves, -mno-xsaves
3945
3946RISCV
3947-----
3948.. option:: -msave-restore, -mno-save-restore
3949
3950Enable using library calls for save and restore
3951
3952Long double flags
3953-----------------
3954Selects the long double implementation
3955
3956.. option:: -mlong-double-128
3957
3958Force long double to be 128 bits
3959
3960.. option:: -mlong-double-64
3961
3962Force long double to be 64 bits
3963
3964.. option:: -mlong-double-80
3965
3966Force long double to be 80 bits, padded to 128 bits for storage
3967
3968Optimization level
3969~~~~~~~~~~~~~~~~~~
3970
3971Flags controlling how much optimization should be performed.
3972
3973.. option:: -O<arg>, -O (equivalent to -O1), --optimize, --optimize=<arg>
3974
3975.. option:: -Ofast<arg>
3976
3977Debug information generation
3978~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3979
3980Flags controlling how much and what kind of debug information should be
3981generated.
3982
3983Kind and level of debug information
3984-----------------------------------
3985.. option:: -g, --debug, --debug=<arg>
3986
3987Generate source-level debug information
3988
3989.. option:: -gdwarf
3990
3991Generate source-level debug information with the default dwarf version
3992
3993.. option:: -gdwarf-2
3994
3995Generate source-level debug information with dwarf version 2
3996
3997.. option:: -gdwarf-3
3998
3999Generate source-level debug information with dwarf version 3
4000
4001.. option:: -gdwarf-4
4002
4003Generate source-level debug information with dwarf version 4
4004
4005.. option:: -gdwarf-5
4006
4007Generate source-level debug information with dwarf version 5
4008
4009.. option:: -gdwarf32
4010
4011Enables DWARF32 format for ELF binaries, if debug information emission is enabled.
4012
4013.. option:: -gdwarf64
4014
4015Enables DWARF64 format for ELF binaries, if debug information emission is enabled.
4016
4017.. option:: -gfull
4018
4019.. option:: -ginline-line-tables, -gno-inline-line-tables
4020
4021.. option:: -gused
4022
4023Debug level
4024___________
4025.. option:: -g0
4026
4027.. option:: -g2
4028
4029.. option:: -g3
4030
4031.. option:: -ggdb0
4032
4033.. option:: -ggdb1
4034
4035.. option:: -ggdb2
4036
4037.. option:: -ggdb3
4038
4039.. option:: -gline-directives-only
4040
4041Emit debug line info directives only
4042
4043.. option:: -gline-tables-only, -g1, -gmlt
4044
4045Emit debug line number tables only
4046
4047.. option:: -gmodules
4048
4049Generate debug info with external references to clang modules or precompiled headers
4050
4051Debugger to tune debug information for
4052______________________________________
4053.. option:: -gdbx
4054
4055.. option:: -ggdb
4056
4057.. option:: -glldb
4058
4059.. option:: -gsce
4060
4061Debug information flags
4062-----------------------
4063.. option:: -gcolumn-info, -gno-column-info
4064
4065.. option:: -gdwarf-aranges
4066
4067.. option:: -gembed-source, -gno-embed-source
4068
4069Embed source text in DWARF debug sections
4070
4071.. option:: -ggnu-pubnames, -gno-gnu-pubnames
4072
4073.. option:: -gpubnames, -gno-pubnames
4074
4075.. option:: -grecord-command-line, -gno-record-command-line, -grecord-gcc-switches
4076
4077.. option:: -gsimple-template-names, -gno-simple-template-names
4078
4079.. option:: -gsplit-dwarf, -gno-split-dwarf
4080
4081.. program:: clang1
4082.. option:: -gsplit-dwarf=<arg>
4083.. program:: clang
4084
4085Set DWARF fission mode. <arg> must be 'split' or 'single'.
4086
4087.. option:: -gstrict-dwarf, -gno-strict-dwarf
4088
4089.. option:: -gz=<arg>, -gz (equivalent to -gz=zlib)
4090
4091DWARF debug sections compression type
4092
4093Static analyzer flags
4094=====================
4095
4096Flags controlling the behavior of the Clang Static Analyzer.
4097
4098.. option:: -Xanalyzer <arg>
4099
4100Pass <arg> to the static analyzer
4101
4102Fortran compilation flags
4103=========================
4104
4105Flags that will be passed onto the ``gfortran`` compiler when Clang is given
4106a Fortran input.
4107
4108.. option:: -A<arg>, --assert <arg>, --assert=<arg>
4109
4110.. option:: -A-<arg>
4111
4112.. option:: -faggressive-function-elimination, -fno-aggressive-function-elimination
4113
4114.. option:: -falign-commons, -fno-align-commons
4115
4116.. option:: -fall-intrinsics, -fno-all-intrinsics
4117
4118.. option:: -fbacktrace, -fno-backtrace
4119
4120.. option:: -fblas-matmul-limit=<arg>
4121
4122.. option:: -fbounds-check, -fno-bounds-check
4123
4124.. option:: -fcheck-array-temporaries, -fno-check-array-temporaries
4125
4126.. option:: -fcheck=<arg>
4127
4128.. option:: -fcoarray=<arg>
4129
4130.. option:: -fconvert=<arg>
4131
4132.. option:: -fcray-pointer, -fno-cray-pointer
4133
4134.. option:: -fd-lines-as-code, -fno-d-lines-as-code
4135
4136.. option:: -fd-lines-as-comments, -fno-d-lines-as-comments
4137
4138.. option:: -fdollar-ok, -fno-dollar-ok
4139
4140.. option:: -fdump-fortran-optimized, -fno-dump-fortran-optimized
4141
4142.. option:: -fdump-fortran-original, -fno-dump-fortran-original
4143
4144.. option:: -fdump-parse-tree, -fno-dump-parse-tree
4145
4146.. option:: -fexternal-blas, -fno-external-blas
4147
4148.. option:: -ff2c, -fno-f2c
4149
4150.. option:: -ffpe-trap=<arg>
4151
4152.. option:: -ffree-line-length-<arg>
4153
4154.. option:: -ffrontend-optimize, -fno-frontend-optimize
4155
4156.. option:: -finit-character=<arg>
4157
4158.. option:: -finit-integer=<arg>
4159
4160.. option:: -finit-local-zero, -fno-init-local-zero
4161
4162.. option:: -finit-logical=<arg>
4163
4164.. option:: -finit-real=<arg>
4165
4166.. option:: -finteger-4-integer-8, -fno-integer-4-integer-8
4167
4168.. option:: -fmax-array-constructor=<arg>
4169
4170.. option:: -fmax-errors=<arg>
4171
4172.. option:: -fmax-identifier-length, -fno-max-identifier-length
4173
4174.. option:: -fmax-stack-var-size=<arg>
4175
4176.. option:: -fmax-subrecord-length=<arg>
4177
4178.. option:: -fmodule-private, -fno-module-private
4179
4180.. option:: -fpack-derived, -fno-pack-derived
4181
4182.. option:: -frange-check, -fno-range-check
4183
4184.. option:: -freal-4-real-10, -fno-real-4-real-10
4185
4186.. option:: -freal-4-real-16, -fno-real-4-real-16
4187
4188.. option:: -freal-4-real-8, -fno-real-4-real-8
4189
4190.. option:: -freal-8-real-10, -fno-real-8-real-10
4191
4192.. option:: -freal-8-real-16, -fno-real-8-real-16
4193
4194.. option:: -freal-8-real-4, -fno-real-8-real-4
4195
4196.. option:: -frealloc-lhs, -fno-realloc-lhs
4197
4198.. option:: -frecord-marker=<arg>
4199
4200.. option:: -frecursive, -fno-recursive
4201
4202.. option:: -frepack-arrays, -fno-repack-arrays
4203
4204.. option:: -fsecond-underscore, -fno-second-underscore
4205
4206.. option:: -fsign-zero, -fno-sign-zero
4207
4208.. option:: -fstack-arrays, -fno-stack-arrays
4209
4210.. option:: -funderscoring, -fno-underscoring
4211
4212.. option:: -fwhole-file, -fno-whole-file
4213
4214.. option:: -imultilib <arg>
4215
4216.. option:: -static-libgfortran
4217
4218Linker flags
4219============
4220Flags that are passed on to the linker
4221
4222.. option:: -L<dir>, --library-directory <arg>, --library-directory=<arg>
4223
4224Add directory to library search path
4225
4226.. option:: -Mach
4227
4228.. option:: -T<script>
4229
4230Specify <script> as linker script
4231
4232.. option:: -Tbss<addr>
4233
4234Set starting address of BSS to <addr>
4235
4236.. option:: -Tdata<addr>
4237
4238Set starting address of DATA to <addr>
4239
4240.. option:: -Ttext<addr>
4241
4242Set starting address of TEXT to <addr>
4243
4244.. option:: -Wl,<arg>,<arg2>...
4245
4246Pass the comma separated arguments in <arg> to the linker
4247
4248.. option:: -X
4249
4250.. option:: -Xlinker <arg>, --for-linker <arg>, --for-linker=<arg>
4251
4252Pass <arg> to the linker
4253
4254.. option:: -Xoffload-linker<triple> <arg>
4255
4256Pass <arg> to the offload linkers or the ones idenfied by -<triple>
4257
4258.. program:: clang1
4259.. option:: -Z
4260.. program:: clang
4261
4262.. option:: -b<arg>
4263
4264Pass -b <arg> to the linker on AIX (only).
4265
4266.. option:: -coverage, --coverage
4267
4268.. option:: -e<arg>, --entry
4269
4270.. option:: -filelist <arg>
4271
4272.. option:: --hip-device-lib=<arg>
4273
4274HIP device library
4275
4276.. option:: --hipspv-pass-plugin=<dsopath>
4277
4278path to a pass plugin for HIP to SPIR-V passes.
4279
4280.. option:: -l<arg>
4281
4282.. option:: --ld-path=<arg>
4283
4284.. option:: -nostartfiles
4285
4286.. program:: clang1
4287.. option:: -nostdlib, --no-standard-libraries
4288.. program:: clang
4289
4290.. option:: --offload-link
4291
4292Use the new offloading linker to perform the link job.
4293
4294.. option:: -pie
4295
4296.. option:: -r
4297
4298.. option:: -rdynamic
4299
4300.. option:: --rocm-device-lib-path=<arg>, --hip-device-lib-path=<arg>
4301
4302ROCm device library path. Alternative to rocm-path.
4303
4304.. option:: -rpath <arg>
4305
4306.. option:: -s
4307
4308.. option:: -shared, --shared
4309
4310.. option:: -specs=<arg>, --specs=<arg>
4311
4312.. option:: -static, --static
4313
4314.. option:: -static-pie
4315
4316.. option:: -t
4317
4318.. option:: -u<arg>, --force-link <arg>, --force-link=<arg>
4319
4320.. option:: -undef
4321
4322undef all system defines
4323
4324.. option:: -undefined<arg>, --no-undefined
4325
4326.. option:: -z <arg>
4327
4328Pass -z <arg> to the linker
4329
4330<clang-dxc options>
4331===================
4332dxc compatibility options
4333
4334.. program:: clang3
4335.. option:: /T<profile>, -T<profile>
4336.. program:: clang
4337
4338Set target profile. <profile> must be 'ps_6_0', ' ps_6_1', ' ps_6_2', ' ps_6_3', ' ps_6_4', ' ps_6_5', ' ps_6_6', ' ps_6_7', 'vs_6_0', ' vs_6_1', ' vs_6_2', ' vs_6_3', ' vs_6_4', ' vs_6_5', ' vs_6_6', ' vs_6_7', 'gs_6_0', ' gs_6_1', ' gs_6_2', ' gs_6_3', ' gs_6_4', ' gs_6_5', ' gs_6_6', ' gs_6_7', 'hs_6_0', ' hs_6_1', ' hs_6_2', ' hs_6_3', ' hs_6_4', ' hs_6_5', ' hs_6_6', ' hs_6_7', 'ds_6_0', ' ds_6_1', ' ds_6_2', ' ds_6_3', ' ds_6_4', ' ds_6_5', ' ds_6_6', ' ds_6_7', 'cs_6_0', ' cs_6_1', ' cs_6_2', ' cs_6_3', ' cs_6_4', ' cs_6_5', ' cs_6_6', ' cs_6_7', 'lib_6_3', ' lib_6_4', ' lib_6_5', ' lib_6_6', ' lib_6_7', ' lib_6_x', 'ms_6_5', ' ms_6_6', ' ms_6_7', 'as_6_5', ' as_6_6' or ' as_6_7'.
4339
4340.. program:: clang4
4341.. option:: /emit-pristine-llvm, -emit-pristine-llvm, /fcgl, -fcgl
4342.. program:: clang
4343
4344Emit pristine LLVM IR from the frontend by not running any LLVM passes at all.Same as -S + -emit-llvm + -disable-llvm-passes.
4345
4346.. program:: clang5
4347.. option:: /hlsl-no-stdinc, -hlsl-no-stdinc
4348.. program:: clang
4349
4350HLSL only. Disables all standard includes containing non-native compiler types and functions.
4351
4352