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 $prefix/$triple-$file and $prefix$file for executables, libraries, includes, and data files used by the compiler. $prefix may or may not be a directory
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:: -Xopenmp-target <arg>
80
81Pass <arg> to the target offloading toolchain.
82
83.. program:: clang1
84.. option:: -Xopenmp-target=<triple> <arg>
85.. program:: clang
86
87Pass <arg> to the target offloading toolchain identified by <triple>.
88
89.. option:: -Z<arg>
90
91.. option:: -a<arg>, --profile-blocks
92
93.. option:: -all\_load
94
95.. option:: -allowable\_client <arg>
96
97.. option:: --analyze
98
99Run the static analyzer
100
101.. option:: --analyzer-no-default-checks
102
103.. option:: --analyzer-output<arg>
104
105Static analyzer report output format (html\|plist\|plist-multi-file\|plist-html\|sarif\|sarif-html\|text).
106
107.. option:: -arch <arg>
108
109.. program:: clang1
110.. option:: -arch\_errors\_fatal
111.. program:: clang
112
113.. program:: clang2
114.. option:: -arch\_only <arg>
115.. program:: clang
116
117.. option:: -arcmt-migrate-emit-errors
118
119Emit ARC errors even if the migrator can fix them
120
121.. option:: -arcmt-migrate-report-output <arg>
122
123Output path for the plist report
124
125.. option:: --autocomplete=<arg>
126
127.. option:: -bind\_at\_load
128
129.. option:: -bundle
130
131.. program:: clang1
132.. option:: -bundle\_loader <arg>
133.. program:: clang
134
135.. option:: -client\_name<arg>
136
137.. option:: -compatibility\_version<arg>
138
139.. option:: --config <arg>
140
141Specifies configuration file
142
143.. option:: --constant-cfstrings
144
145.. option:: --cuda-compile-host-device
146
147Compile CUDA code for both host and device (default).  Has no effect on non-CUDA compilations.
148
149.. option:: --cuda-device-only
150
151Compile CUDA code for device only
152
153.. option:: --cuda-host-only
154
155Compile CUDA code for host only.  Has no effect on non-CUDA compilations.
156
157.. option:: --cuda-include-ptx=<arg>, --no-cuda-include-ptx=<arg>
158
159Include PTX for the following GPU architecture (e.g. sm\_35) or 'all'. May be specified more than once.
160
161.. option:: --cuda-noopt-device-debug, --no-cuda-noopt-device-debug
162
163Enable device-side debug info generation. Disables ptxas optimizations.
164
165.. option:: -cuid=<arg>
166
167An 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.
168
169.. option:: -current\_version<arg>
170
171.. option:: -dead\_strip
172
173.. option:: -dependency-dot <arg>
174
175Filename to write DOT-formatted header dependencies to
176
177.. option:: -dependency-file <arg>
178
179Filename (or -) to write dependency output to
180
181.. option:: -dsym-dir<dir>
182
183Directory to output dSYM's (if any) to
184
185.. option:: -dumpmachine
186
187.. option:: -dumpversion
188
189.. option:: --dyld-prefix=<arg>, --dyld-prefix <arg>
190
191.. option:: -dylib\_file <arg>
192
193.. option:: -dylinker
194
195.. program:: clang1
196.. option:: -dylinker\_install\_name<arg>
197.. program:: clang
198
199.. option:: -dynamic
200
201.. option:: -dynamiclib
202
203.. option:: -emit-ast
204
205Emit Clang AST files for source inputs
206
207.. option:: --emit-static-lib
208
209Enable linker job to emit a static library.
210
211.. option:: -enable-trivial-auto-var-init-zero-knowing-it-will-be-removed-from-clang
212
213Trivial 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
214
215.. option:: -exported\_symbols\_list <arg>
216
217.. option:: -faligned-new=<arg>
218
219.. option:: -ffixed-r19
220
221Reserve register r19 (Hexagon only)
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:: -framework <arg>
246
247.. option:: -frtlib-add-rpath, -fno-rtlib-add-rpath
248
249Add -rpath with architecture-specific resource directory to the linker flags
250
251.. option:: -fsanitize-system-ignorelist=<arg>, -fsanitize-system-blacklist=<arg>
252
253Path to system ignorelist file for sanitizers
254
255.. option:: -fshow-skipped-includes
256
257#include files may be "skipped" due to include guard optimization
258             or #pragma once. This flag makes -H show also such includes.
259
260.. option:: -fsystem-module
261
262Build this module as a system module. Only used with -emit-module
263
264.. option:: -fuse-cuid=<arg>
265
266Method 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 overriden by option '-cuid=\[ID\]' if it is specified.
267
268.. option:: --gcc-toolchain=<arg>, -gcc-toolchain <arg>
269
270Search for GCC installation in the specified directory on targets which commonly use GCC. The directory usually contains 'lib{,32,64}/gcc{,-cross}/$triple' and 'include'. If specified, sysroot is skipped for GCC detection. Note: executables (e.g. ld) used by the compiler are not overridden by the selected GCC installation
271
272.. option:: -gcodeview
273
274Generate CodeView debug information
275
276.. option:: -gcodeview-ghash, -gno-codeview-ghash
277
278Emit type record hashes in a .debug$H section
279
280.. option:: --gpu-instrument-lib=<arg>
281
282Instrument device library for HIP, which is a LLVM bitcode containing \_\_cyg\_profile\_func\_enter and \_\_cyg\_profile\_func\_exit
283
284.. option:: --gpu-max-threads-per-block=<arg>
285
286Default max threads per block for kernel launch bounds for HIP
287
288.. option:: -headerpad\_max\_install\_names<arg>
289
290.. option:: -help, --help
291
292Display available options
293
294.. option:: --help-hidden
295
296Display help for hidden options
297
298.. option:: --hip-link
299
300Link clang-offload-bundler bundles for HIP
301
302.. option:: --hip-version=<arg>
303
304HIP version in the format of major.minor.patch
305
306.. option:: -ibuiltininc
307
308Enable builtin #include directories even when -nostdinc is used before or after -ibuiltininc. Using -nobuiltininc after the option disables it
309
310.. option:: -image\_base <arg>
311
312.. option:: -index-header-map
313
314Make the next included directory (-I or -F) an indexer header map
315
316.. option:: -init <arg>
317
318.. option:: -install\_name <arg>
319
320.. option:: -interface-stub-version=<arg>
321
322.. option:: -keep\_private\_externs
323
324.. option:: -lazy\_framework <arg>
325
326.. program:: clang1
327.. option:: -lazy\_library <arg>
328.. program:: clang
329
330.. option:: -mbig-endian, -EB
331
332.. option:: -mbranch-protection=<arg>
333
334Enforce targets of indirect branches and function returns
335
336.. option:: -menable-unsafe-fp-math
337
338Allow unsafe floating-point math optimizations which may decrease precision
339
340.. option:: -mharden-sls=<arg>
341
342Select straight-line speculation hardening scope
343
344.. option:: --migrate
345
346Run the migrator
347
348.. option:: -mios-simulator-version-min=<arg>, -miphonesimulator-version-min=<arg>
349
350.. option:: -mlinker-version=<arg>
351
352.. option:: -mlittle-endian, -EL
353
354.. option:: -mllvm <arg>
355
356Additional arguments to forward to LLVM's option processing
357
358.. option:: -module-dependency-dir <arg>
359
360Directory to dump module dependencies to
361
362.. option:: -mtvos-simulator-version-min=<arg>, -mappletvsimulator-version-min=<arg>
363
364.. option:: -multi\_module
365
366.. option:: -multiply\_defined <arg>
367
368.. program:: clang1
369.. option:: -multiply\_defined\_unused <arg>
370.. program:: clang
371
372.. option:: -mwatchos-simulator-version-min=<arg>, -mwatchsimulator-version-min=<arg>
373
374.. option:: --no-cuda-version-check
375
376Don't error out if the detected version of the CUDA install is too low for the requested CUDA gpu architecture.
377
378.. option:: -no-integrated-cpp, --no-integrated-cpp
379
380.. option:: -no\_dead\_strip\_inits\_and\_terms
381
382.. option:: -nobuiltininc
383
384Disable builtin #include directories
385
386.. option:: -nodefaultlibs
387
388.. option:: -nofixprebinding
389
390.. option:: -nogpuinc, -nocudainc
391
392Do not add include paths for CUDA/HIP and do not include the default CUDA/HIP wrapper headers
393
394.. option:: -nogpulib, -nocudalib
395
396Do not link device library for CUDA/HIP device compilation
397
398.. option:: -nolibc
399
400.. option:: -nomultidefs
401
402.. option:: -nopie, -no-pie
403
404.. option:: -noprebind
405
406.. option:: -noprofilelib
407
408.. option:: -noseglinkedit
409
410.. option:: -nostdinc, --no-standard-includes
411
412.. program:: clang1
413.. option:: -nostdinc++
414.. program:: clang
415
416Disable standard #include directories for the C++ standard library
417
418.. option:: -nostdlib++
419
420.. option:: -nostdlibinc
421
422.. option:: -o<file>, --output <arg>, --output=<arg>
423
424Write output to <file>
425
426.. option:: -objcmt-atomic-property
427
428Make migration to 'atomic' properties
429
430.. option:: -objcmt-migrate-all
431
432Enable migration to modern ObjC
433
434.. option:: -objcmt-migrate-annotation
435
436Enable migration to property and method annotations
437
438.. option:: -objcmt-migrate-designated-init
439
440Enable migration to infer NS\_DESIGNATED\_INITIALIZER for initializer methods
441
442.. option:: -objcmt-migrate-instancetype
443
444Enable migration to infer instancetype for method result type
445
446.. option:: -objcmt-migrate-literals
447
448Enable migration to modern ObjC literals
449
450.. option:: -objcmt-migrate-ns-macros
451
452Enable migration to NS\_ENUM/NS\_OPTIONS macros
453
454.. option:: -objcmt-migrate-property
455
456Enable migration to modern ObjC property
457
458.. option:: -objcmt-migrate-property-dot-syntax
459
460Enable migration of setter/getter messages to property-dot syntax
461
462.. option:: -objcmt-migrate-protocol-conformance
463
464Enable migration to add protocol conformance on classes
465
466.. option:: -objcmt-migrate-readonly-property
467
468Enable migration to modern ObjC readonly property
469
470.. option:: -objcmt-migrate-readwrite-property
471
472Enable migration to modern ObjC readwrite property
473
474.. option:: -objcmt-migrate-subscripting
475
476Enable migration to modern ObjC subscripting
477
478.. option:: -objcmt-ns-nonatomic-iosonly
479
480Enable migration to use NS\_NONATOMIC\_IOSONLY macro for setting property's 'atomic' attribute
481
482.. option:: -objcmt-returns-innerpointer-property
483
484Enable migration to annotate property with NS\_RETURNS\_INNER\_POINTER
485
486.. option:: -objcmt-whitelist-dir-path=<arg>, -objcmt-white-list-dir-path=<arg>
487
488Only modify files with a filename contained in the provided directory path
489
490.. option:: -object
491
492.. option:: --offload-arch=<arg>, --cuda-gpu-arch=<arg>, --no-offload-arch=<arg>
493
494CUDA 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.
495
496.. option:: -p, --profile
497
498.. option:: -pagezero\_size<arg>
499
500.. option:: -pg
501
502Enable mcount instrumentation
503
504.. option:: -pipe, --pipe
505
506Use pipes between commands, when possible
507
508.. option:: -prebind
509
510.. program:: clang1
511.. option:: -prebind\_all\_twolevel\_modules
512.. program:: clang
513
514.. option:: -preload
515
516.. option:: --print-diagnostic-categories
517
518.. option:: -print-effective-triple, --print-effective-triple
519
520Print the effective target triple
521
522.. option:: -print-file-name=<file>, --print-file-name=<file>, --print-file-name <arg>
523
524Print the full library path of <file>
525
526.. option:: -print-ivar-layout
527
528Enable Objective-C Ivar layout bitmap print trace
529
530.. option:: -print-libgcc-file-name, --print-libgcc-file-name
531
532Print the library path for the currently used compiler runtime library ("libgcc.a" or "libclang\_rt.builtins.\*.a")
533
534.. option:: -print-multi-directory, --print-multi-directory
535
536.. option:: -print-multi-lib, --print-multi-lib
537
538.. option:: -print-multiarch, --print-multiarch
539
540Print the multiarch target triple
541
542.. option:: -print-prog-name=<name>, --print-prog-name=<name>, --print-prog-name <arg>
543
544Print the full program path of <name>
545
546.. option:: -print-resource-dir, --print-resource-dir
547
548Print the resource directory pathname
549
550.. option:: -print-rocm-search-dirs, --print-rocm-search-dirs
551
552Print the paths used for finding ROCm installation
553
554.. option:: -print-runtime-dir, --print-runtime-dir
555
556Print the directory pathname containing clangs runtime libraries
557
558.. option:: -print-search-dirs, --print-search-dirs
559
560Print the paths used for finding libraries and programs
561
562.. option:: -print-target-triple, --print-target-triple
563
564Print the normalized target triple
565
566.. option:: -print-targets, --print-targets
567
568Print the registered targets
569
570.. option:: -private\_bundle
571
572.. option:: -pthread, -no-pthread
573
574Support POSIX threads in generated code
575
576.. option:: -pthreads
577
578.. option:: -read\_only\_relocs <arg>
579
580.. option:: -relocatable-pch, --relocatable-pch
581
582Whether to build a relocatable precompiled header
583
584.. option:: -remap
585
586.. option:: -rewrite-legacy-objc
587
588Rewrite Legacy Objective-C source to C++
589
590.. option:: -rtlib=<arg>, --rtlib=<arg>, --rtlib <arg>
591
592Compiler runtime library to use
593
594.. option:: -save-stats=<arg>, --save-stats=<arg>, -save-stats (equivalent to -save-stats=cwd), --save-stats (equivalent to -save-stats=cwd)
595
596Save llvm statistics.
597
598.. option:: -save-temps=<arg>, --save-temps=<arg>, -save-temps (equivalent to -save-temps=cwd), --save-temps (equivalent to -save-temps=cwd)
599
600Save intermediate compilation results.
601
602.. option:: -sectalign <arg1> <arg2> <arg3>
603
604.. option:: -sectcreate <arg1> <arg2> <arg3>
605
606.. option:: -sectobjectsymbols <arg1> <arg2>
607
608.. option:: -sectorder <arg1> <arg2> <arg3>
609
610.. option:: -seg1addr<arg>
611
612.. option:: -seg\_addr\_table <arg>
613
614.. program:: clang1
615.. option:: -seg\_addr\_table\_filename <arg>
616.. program:: clang
617
618.. option:: -segaddr <arg1> <arg2>
619
620.. option:: -segcreate <arg1> <arg2> <arg3>
621
622.. option:: -seglinkedit
623
624.. option:: -segprot <arg1> <arg2> <arg3>
625
626.. option:: -segs\_read\_<arg>
627
628.. program:: clang1
629.. option:: -segs\_read\_only\_addr <arg>
630.. program:: clang
631
632.. program:: clang2
633.. option:: -segs\_read\_write\_addr <arg>
634.. program:: clang
635
636.. option:: -serialize-diagnostics <arg>, --serialize-diagnostics <arg>
637
638Serialize compiler diagnostics to a file
639
640.. option:: -shared-libgcc
641
642.. option:: -shared-libsan, -shared-libasan
643
644Dynamically link the sanitizer runtime
645
646.. option:: -single\_module
647
648.. option:: -static-libgcc
649
650.. option:: -static-libsan
651
652Statically link the sanitizer runtime
653
654.. option:: -static-libstdc++
655
656.. option:: -static-openmp
657
658Use the static host OpenMP runtime while linking.
659
660.. option:: -std-default=<arg>
661
662.. option:: -stdlib=<arg>, --stdlib=<arg>, --stdlib <arg>
663
664C++ standard library to use
665
666.. option:: -sub\_library<arg>
667
668.. program:: clang1
669.. option:: -sub\_umbrella<arg>
670.. program:: clang
671
672.. option:: --sysroot=<arg>, --sysroot <arg>
673
674.. option:: --target-help
675
676.. option:: --target=<arg>, -target <arg>
677
678Generate code for the given target
679
680.. option:: -time
681
682Time individual commands
683
684.. option:: -traditional, --traditional
685
686.. option:: -traditional-cpp, --traditional-cpp
687
688Enable some traditional CPP emulation
689
690.. option:: -twolevel\_namespace
691
692.. program:: clang1
693.. option:: -twolevel\_namespace\_hints
694.. program:: clang
695
696.. option:: -umbrella <arg>
697
698.. option:: -unexported\_symbols\_list <arg>
699
700.. option:: -unwindlib=<arg>, --unwindlib=<arg>
701
702Unwind library to use
703
704.. option:: -v, --verbose
705
706Show commands to run and use verbose output
707
708.. option:: --verify-debug-info
709
710Verify the binary representation of debug output
711
712.. option:: --version
713
714Print version information
715
716.. option:: -w, --no-warnings
717
718Suppress all warnings
719
720.. option:: -weak-l<arg>
721
722.. option:: -weak\_framework <arg>
723
724.. program:: clang1
725.. option:: -weak\_library <arg>
726.. program:: clang
727
728.. program:: clang2
729.. option:: -weak\_reference\_mismatches <arg>
730.. program:: clang
731
732.. option:: -whatsloaded
733
734.. option:: -why\_load, -whyload
735
736.. option:: -working-directory<arg>, -working-directory=<arg>
737
738Resolve file paths relative to the specified directory
739
740.. option:: -x<language>, --language <arg>, --language=<arg>
741
742Treat subsequent input files as having type <language>
743
744.. option:: -y<arg>
745
746Actions
747=======
748The action to perform on the input.
749
750.. option:: -E, --preprocess
751
752Only run the preprocessor
753
754.. option:: -S, --assemble
755
756Only run preprocess and compilation steps
757
758.. option:: -c, --compile
759
760Only run preprocess, compile, and assemble steps
761
762.. option:: -emit-interface-stubs
763
764Generate Interface Stub Files.
765
766.. option:: -emit-llvm
767
768Use the LLVM representation for assembler and object files
769
770.. option:: -emit-merged-ifs
771
772Generate Interface Stub Files, emit merged text not binary.
773
774.. option:: -fsyntax-only
775
776.. option:: -module-file-info
777
778Provide information about a particular module file
779
780.. option:: --precompile
781
782Only precompile the input
783
784.. option:: -rewrite-objc
785
786Rewrite Objective-C source to C++
787
788.. option:: -verify-pch
789
790Load and verify that a pre-compiled header file is not stale
791
792Compilation flags
793=================
794
795Flags controlling the behavior of Clang during compilation. These flags have
796no effect during actions that do not perform compilation.
797
798.. option:: -Xassembler <arg>
799
800Pass <arg> to the assembler
801
802.. option:: -Xclang <arg>
803
804Pass <arg> to the clang compiler
805
806.. option:: -ansi, --ansi
807
808.. option:: -fc++-abi=<arg>
809
810C++ ABI to use. This will override the target C++ ABI.
811
812.. option:: -fclang-abi-compat=<version>
813
814Attempt to match the ABI of Clang <version>
815
816.. option:: -fcomment-block-commands=<arg>,<arg2>...
817
818Treat each comma separated argument in <arg> as a documentation comment block command
819
820.. option:: -fcomplete-member-pointers, -fno-complete-member-pointers
821
822Require member pointer base types to be complete if they would be significant under the Microsoft ABI
823
824.. option:: -fcrash-diagnostics-dir=<dir>
825
826Put crash-report files in <dir>
827
828.. option:: -fdeclspec, -fno-declspec
829
830Allow \_\_declspec as a keyword
831
832.. option:: -fdepfile-entry=<arg>
833
834.. option:: -fdiagnostics-fixit-info, -fno-diagnostics-fixit-info
835
836.. option:: -fdiagnostics-format=<arg>
837
838.. option:: -fdiagnostics-parseable-fixits
839
840Print fix-its in machine parseable form
841
842.. option:: -fdiagnostics-print-source-range-info
843
844Print source range spans in numeric form
845
846.. option:: -fdiagnostics-show-category=<arg>
847
848.. option:: -fdiscard-value-names, -fno-discard-value-names
849
850Discard value names in LLVM IR
851
852.. option:: -fexperimental-relative-c++-abi-vtables, -fno-experimental-relative-c++-abi-vtables
853
854Use the experimental C++ class ABI for classes with virtual tables
855
856.. option:: -fexperimental-strict-floating-point
857
858Enables experimental strict floating point in LLVM.
859
860.. option:: -ffine-grained-bitfield-accesses, -fno-fine-grained-bitfield-accesses
861
862Use separate accesses for consecutive bitfield runs with legal widths and alignments.
863
864.. option:: -fglobal-isel, -fexperimental-isel, -fno-global-isel
865
866Enables the global instruction selector
867
868.. option:: -finline-functions, -fno-inline-functions
869
870Inline suitable functions
871
872.. option:: -finline-hint-functions
873
874Inline functions which are (explicitly or implicitly) marked inline
875
876.. option:: -flegacy-pass-manager, -fno-experimental-new-pass-manager, -fno-legacy-pass-manager
877
878Use the legacy pass manager in LLVM
879
880.. option:: -fno-crash-diagnostics
881
882Disable auto-generation of preprocessed source files and a script for reproduction during a clang crash
883
884.. option:: -fno-sanitize-ignorelist, -fno-sanitize-blacklist
885
886Don't use ignorelist file for sanitizers
887
888.. option:: -fparse-all-comments
889
890.. option:: -frecord-command-line, -fno-record-command-line, -frecord-gcc-switches
891
892.. option:: -fsanitize-address-destructor=<arg>
893
894Set destructor type used in ASan instrumentation
895
896.. option:: -fsanitize-address-field-padding=<arg>
897
898Level of field padding for AddressSanitizer
899
900.. option:: -fsanitize-address-globals-dead-stripping
901
902Enable linker dead stripping of globals in AddressSanitizer
903
904.. option:: -fsanitize-address-poison-custom-array-cookie, -fno-sanitize-address-poison-custom-array-cookie
905
906Enable poisoning array cookies when using custom operator new\[\] in AddressSanitizer
907
908.. option:: -fsanitize-address-use-after-return=<mode>
909
910Select the mode of detecting stack use-after-return in AddressSanitizer
911
912.. option:: -fsanitize-address-use-after-scope, -fno-sanitize-address-use-after-scope
913
914Enable use-after-scope detection in AddressSanitizer
915
916.. option:: -fsanitize-address-use-odr-indicator, -fno-sanitize-address-use-odr-indicator
917
918Enable ODR indicator globals to avoid false ODR violation reports in partially sanitized programs at the cost of an increase in binary size
919
920.. option:: -fsanitize-cfi-canonical-jump-tables, -fno-sanitize-cfi-canonical-jump-tables
921
922Make the jump table addresses canonical in the symbol table
923
924.. option:: -fsanitize-cfi-cross-dso, -fno-sanitize-cfi-cross-dso
925
926Enable control flow integrity (CFI) checks for cross-DSO calls.
927
928.. option:: -fsanitize-cfi-icall-generalize-pointers
929
930Generalize pointers in CFI indirect call type signature checks
931
932.. option:: -fsanitize-coverage-allowlist=<arg>, -fsanitize-coverage-whitelist=<arg>
933
934Restrict sanitizer coverage instrumentation exclusively to modules and functions that match the provided special case list, except the blocked ones
935
936.. option:: -fsanitize-coverage-ignorelist=<arg>, -fsanitize-coverage-blacklist=<arg>
937
938Disable sanitizer coverage instrumentation for modules and functions that match the provided special case list, even the allowed ones
939
940.. option:: -fsanitize-coverage=<arg1>,<arg2>..., -fno-sanitize-coverage=<arg1>,<arg2>...
941
942Specify the type of coverage instrumentation for Sanitizers
943
944.. option:: -fsanitize-hwaddress-abi=<arg>
945
946Select the HWAddressSanitizer ABI to target (interceptor or platform, default interceptor). This option is currently unused.
947
948.. option:: -fsanitize-hwaddress-experimental-aliasing, -fno-sanitize-hwaddress-experimental-aliasing
949
950Enable aliasing mode in HWAddressSanitizer
951
952.. option:: -fsanitize-ignorelist=<arg>, -fsanitize-blacklist=<arg>
953
954Path to ignorelist file for sanitizers
955
956.. option:: -fsanitize-link-c++-runtime, -fno-sanitize-link-c++-runtime
957
958.. option:: -fsanitize-link-runtime, -fno-sanitize-link-runtime
959
960.. option:: -fsanitize-memory-track-origins, -fno-sanitize-memory-track-origins
961
962Enable origins tracking in MemorySanitizer
963
964.. program:: clang1
965.. option:: -fsanitize-memory-track-origins=<arg>
966.. program:: clang
967
968Enable origins tracking in MemorySanitizer
969
970.. option:: -fsanitize-memory-use-after-dtor, -fno-sanitize-memory-use-after-dtor
971
972Enable use-after-destroy detection in MemorySanitizer
973
974.. option:: -fsanitize-minimal-runtime, -fno-sanitize-minimal-runtime
975
976.. option:: -fsanitize-recover=<arg1>,<arg2>..., -fno-sanitize-recover=<arg1>,<arg2>..., -fsanitize-recover (equivalent to -fsanitize-recover=all)
977
978Enable recovery for specified sanitizers
979
980.. option:: -fsanitize-stats, -fno-sanitize-stats
981
982Enable sanitizer statistics gathering.
983
984.. option:: -fsanitize-thread-atomics, -fno-sanitize-thread-atomics
985
986Enable atomic operations instrumentation in ThreadSanitizer (default)
987
988.. option:: -fsanitize-thread-func-entry-exit, -fno-sanitize-thread-func-entry-exit
989
990Enable function entry/exit instrumentation in ThreadSanitizer (default)
991
992.. option:: -fsanitize-thread-memory-access, -fno-sanitize-thread-memory-access
993
994Enable memory access instrumentation in ThreadSanitizer (default)
995
996.. 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)
997
998Enable trapping for specified sanitizers
999
1000.. option:: -fsanitize-undefined-strip-path-components=<number>
1001
1002Strip (or keep only, if negative) a given number of path components when emitting check metadata.
1003
1004.. option:: -fsanitize=<check>,<arg2>..., -fno-sanitize=<arg1>,<arg2>...
1005
1006Turn on runtime checks for various forms of undefined or suspicious behavior. See user manual for available checks
1007
1008.. option:: -moutline, -mno-outline
1009
1010Enable function outlining (AArch64 only)
1011
1012.. option:: -moutline-atomics, -mno-outline-atomics
1013
1014Generate local calls to out-of-line atomic operations
1015
1016.. option:: --param <arg>, --param=<arg>
1017
1018.. option:: -print-supported-cpus, --print-supported-cpus, -mcpu=?, -mtune=?
1019
1020Print supported cpu models for the given target (if target is not specified, it will print the supported cpus for the default target)
1021
1022.. option:: -std=<arg>, --std=<arg>, --std <arg>
1023
1024Language standard to compile for
1025
1026Preprocessor flags
1027~~~~~~~~~~~~~~~~~~
1028
1029Flags controlling the behavior of the Clang preprocessor.
1030
1031.. option:: -C, --comments
1032
1033Include comments in preprocessed output
1034
1035.. option:: -CC, --comments-in-macros
1036
1037Include comments from within macros in preprocessed output
1038
1039.. option:: -D<macro>=<value>, --define-macro <arg>, --define-macro=<arg>
1040
1041Define <macro> to <value> (or 1 if <value> omitted)
1042
1043.. option:: -H, --trace-includes
1044
1045Show header includes and nesting depth
1046
1047.. option:: -P, --no-line-commands
1048
1049Disable linemarker output in -E mode
1050
1051.. option:: -U<macro>, --undefine-macro <arg>, --undefine-macro=<arg>
1052
1053Undefine macro <macro>
1054
1055.. option:: -Wp,<arg>,<arg2>...
1056
1057Pass the comma separated arguments in <arg> to the preprocessor
1058
1059.. option:: -Xpreprocessor <arg>
1060
1061Pass <arg> to the preprocessor
1062
1063.. option:: -fmacro-prefix-map=<arg>
1064
1065remap file source paths in predefined preprocessor macros
1066
1067Include path management
1068-----------------------
1069
1070Flags controlling how ``#include``\s are resolved to files.
1071
1072.. option:: -I<dir>, --include-directory <arg>, --include-directory=<arg>
1073
1074Add directory to include search path. For C++ inputs, if
1075there are multiple -I options, these directories are searched
1076in the order they are given before the standard system directories
1077are searched. If the same directory is in the SYSTEM include search
1078paths, for example if also specified with -isystem, the -I option
1079will be ignored
1080
1081.. option:: -I-, --include-barrier
1082
1083Restrict all prior -I flags to double-quoted inclusion and remove current directory from include path
1084
1085.. option:: --amdgpu-arch-tool=<arg>
1086
1087Tool used for detecting AMD GPU arch in the system.
1088
1089.. option:: --cuda-path-ignore-env
1090
1091Ignore environment variables to detect CUDA installation
1092
1093.. option:: --cuda-path=<arg>
1094
1095CUDA installation path
1096
1097.. option:: -cxx-isystem<directory>
1098
1099Add directory to the C++ SYSTEM include search path
1100
1101.. option:: -fbuild-session-file=<file>
1102
1103Use the last modification time of <file> as the build session timestamp
1104
1105.. option:: -fbuild-session-timestamp=<time since Epoch in seconds>
1106
1107Time when the current build session started
1108
1109.. option:: -fmodule-file=\[<name>=\]<file>
1110
1111Specify the mapping of module name to precompiled module file, or load a module file if name is omitted.
1112
1113.. option:: -fmodules-cache-path=<directory>
1114
1115Specify the module cache path
1116
1117.. option:: -fmodules-disable-diagnostic-validation
1118
1119Disable validation of the diagnostic options when loading the module
1120
1121.. option:: -fmodules-prune-after=<seconds>
1122
1123Specify the interval (in seconds) after which a module file will be considered unused
1124
1125.. option:: -fmodules-prune-interval=<seconds>
1126
1127Specify the interval (in seconds) between attempts to prune the module cache
1128
1129.. option:: -fmodules-user-build-path <directory>
1130
1131Specify the module user build path
1132
1133.. option:: -fmodules-validate-once-per-build-session
1134
1135Don't verify input files for the modules if the module has been successfully validated or loaded during this build session
1136
1137.. option:: -fmodules-validate-system-headers, -fno-modules-validate-system-headers
1138
1139Validate the system headers that a module depends on when loading the module
1140
1141.. option:: -fprebuilt-module-path=<directory>
1142
1143Specify the prebuilt module path
1144
1145.. option:: --hip-path=<arg>
1146
1147HIP runtime installation path, used for finding HIP version and adding HIP include path.
1148
1149.. option:: -idirafter<arg>, --include-directory-after <arg>, --include-directory-after=<arg>
1150
1151Add directory to AFTER include search path
1152
1153.. option:: -iframework<arg>
1154
1155Add directory to SYSTEM framework search path
1156
1157.. option:: -iframeworkwithsysroot<directory>
1158
1159Add directory to SYSTEM framework search path, absolute paths are relative to -isysroot
1160
1161.. option:: -imacros<file>, --imacros<file>, --imacros=<arg>
1162
1163Include macros from file before parsing
1164
1165.. option:: -include<file>, --include<file>, --include=<arg>
1166
1167Include file before parsing
1168
1169.. option:: -include-pch <file>
1170
1171Include precompiled header file
1172
1173.. option:: -iprefix<dir>, --include-prefix <arg>, --include-prefix=<arg>
1174
1175Set the -iwithprefix/-iwithprefixbefore prefix
1176
1177.. option:: -iquote<directory>
1178
1179Add directory to QUOTE include search path
1180
1181.. option:: -isysroot<dir>
1182
1183Set the system root directory (usually /)
1184
1185.. option:: -isystem<directory>
1186
1187Add directory to SYSTEM include search path
1188
1189.. option:: -isystem-after<directory>
1190
1191Add directory to end of the SYSTEM include search path
1192
1193.. option:: -ivfsoverlay<arg>
1194
1195Overlay the virtual filesystem described by file over the real file system
1196
1197.. option:: -iwithprefix<dir>, --include-with-prefix <arg>, --include-with-prefix-after <arg>, --include-with-prefix-after=<arg>, --include-with-prefix=<arg>
1198
1199Set directory to SYSTEM include search path with prefix
1200
1201.. option:: -iwithprefixbefore<dir>, --include-with-prefix-before <arg>, --include-with-prefix-before=<arg>
1202
1203Set directory to include search path with prefix
1204
1205.. option:: -iwithsysroot<directory>
1206
1207Add directory to SYSTEM include search path, absolute paths are relative to -isysroot
1208
1209.. option:: --libomptarget-amdgcn-bc-path=<arg>
1210
1211Path to libomptarget-amdgcn bitcode library
1212
1213.. option:: --libomptarget-nvptx-bc-path=<arg>
1214
1215Path to libomptarget-nvptx bitcode library
1216
1217.. option:: --ptxas-path=<arg>
1218
1219Path to ptxas (used for compiling CUDA code)
1220
1221.. option:: --rocm-path=<arg>
1222
1223ROCm installation path, used for finding and automatically linking required bitcode libraries.
1224
1225.. program:: clang1
1226.. option:: -stdlib++-isystem<directory>
1227.. program:: clang
1228
1229Use directory as the C++ standard library include path
1230
1231.. option:: --system-header-prefix=<prefix>, --no-system-header-prefix=<prefix>, --system-header-prefix <arg>
1232
1233Treat all #include paths starting with <prefix> as including a system header.
1234
1235Dependency file generation
1236--------------------------
1237
1238Flags controlling generation of a dependency file for ``make``-like build
1239systems.
1240
1241.. option:: -M, --dependencies
1242
1243Like -MD, but also implies -E and writes to stdout by default
1244
1245.. option:: -MD, --write-dependencies
1246
1247Write a depfile containing user and system headers
1248
1249.. option:: -MF<file>
1250
1251Write depfile output from -MMD, -MD, -MM, or -M to <file>
1252
1253.. option:: -MG, --print-missing-file-dependencies
1254
1255Add missing headers to depfile
1256
1257.. option:: -MJ<arg>
1258
1259Write a compilation database entry per input
1260
1261.. option:: -MM, --user-dependencies
1262
1263Like -MMD, but also implies -E and writes to stdout by default
1264
1265.. option:: -MMD, --write-user-dependencies
1266
1267Write a depfile containing user headers
1268
1269.. option:: -MP
1270
1271Create phony target for each dependency (other than main file)
1272
1273.. option:: -MQ<arg>
1274
1275Specify name of main file output to quote in depfile
1276
1277.. option:: -MT<arg>
1278
1279Specify name of main file output in depfile
1280
1281.. option:: -MV
1282
1283Use NMake/Jom format for the depfile
1284
1285Dumping preprocessor state
1286--------------------------
1287
1288Flags allowing the state of the preprocessor to be dumped in various ways.
1289
1290.. option:: -d
1291
1292.. program:: clang1
1293.. option:: -d<arg>
1294.. program:: clang
1295
1296.. option:: -dD
1297
1298Print macro definitions in -E mode in addition to normal output
1299
1300.. option:: -dI
1301
1302Print include directives in -E mode in addition to normal output
1303
1304.. option:: -dM
1305
1306Print macro definitions in -E mode instead of normal output
1307
1308Diagnostic flags
1309~~~~~~~~~~~~~~~~
1310
1311Flags controlling which warnings, errors, and remarks Clang will generate.
1312See the :doc:`full list of warning and remark flags <DiagnosticsReference>`.
1313
1314.. option:: -R<remark>
1315
1316Enable the specified remark
1317
1318.. option:: -Rpass-analysis=<arg>
1319
1320Report transformation analysis from optimization passes whose name matches the given POSIX regular expression
1321
1322.. option:: -Rpass-missed=<arg>
1323
1324Report missed transformations by optimization passes whose name matches the given POSIX regular expression
1325
1326.. option:: -Rpass=<arg>
1327
1328Report transformations performed by optimization passes whose name matches the given POSIX regular expression
1329
1330.. option:: -W<warning>, --extra-warnings, --warn-<arg>, --warn-=<arg>
1331
1332Enable the specified warning
1333
1334.. option:: -Wdeprecated, -Wno-deprecated
1335
1336Enable warnings for deprecated constructs and define \_\_DEPRECATED
1337
1338.. option:: -Wnonportable-cfstrings<arg>, -Wno-nonportable-cfstrings<arg>
1339
1340Target-independent compilation options
1341~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1342.. option:: -Wframe-larger-than=<arg>
1343
1344.. option:: -fPIC, -fno-PIC
1345
1346.. option:: -fPIE, -fno-PIE
1347
1348.. option:: -faccess-control, -fno-access-control
1349
1350.. option:: -faddrsig, -fno-addrsig
1351
1352Emit an address-significance table
1353
1354.. option:: -falign-functions, -fno-align-functions
1355
1356.. program:: clang1
1357.. option:: -falign-functions=<arg>
1358.. program:: clang
1359
1360.. program:: clang1
1361.. option:: -faligned-allocation, -faligned-new, -fno-aligned-allocation
1362.. program:: clang
1363
1364Enable C++17 aligned allocation functions
1365
1366.. option:: -fallow-editor-placeholders, -fno-allow-editor-placeholders
1367
1368Treat editor placeholders as valid source code
1369
1370.. option:: -fallow-unsupported
1371
1372.. option:: -faltivec, -fno-altivec
1373
1374.. option:: -fansi-escape-codes
1375
1376Use ANSI escape codes for diagnostics
1377
1378.. option:: -fapple-kext, -findirect-virtual-calls, -fterminated-vtables
1379
1380Use Apple's kernel extensions ABI
1381
1382.. option:: -fapple-link-rtlib
1383
1384Force linking the clang builtins runtime library
1385
1386.. option:: -fapple-pragma-pack, -fno-apple-pragma-pack
1387
1388Enable Apple gcc-compatible #pragma pack handling
1389
1390.. option:: -fapplication-extension, -fno-application-extension
1391
1392Restrict code to those available for App Extensions
1393
1394.. option:: -fasm, -fno-asm
1395
1396.. option:: -fasm-blocks, -fno-asm-blocks
1397
1398.. option:: -fassociative-math, -fno-associative-math
1399
1400.. option:: -fassume-sane-operator-new, -fno-assume-sane-operator-new
1401
1402.. option:: -fast
1403
1404.. option:: -fastcp
1405
1406.. option:: -fastf
1407
1408.. option:: -fasync-exceptions, -fno-async-exceptions
1409
1410Enable EH Asynchronous exceptions
1411
1412.. option:: -fasynchronous-unwind-tables, -fno-asynchronous-unwind-tables
1413
1414.. option:: -fautolink, -fno-autolink
1415
1416.. option:: -fbasic-block-sections=<arg>
1417
1418Generate labels for each basic block or place each basic block or a subset of basic blocks in its own section.
1419
1420.. option:: -fbinutils-version=<major.minor>
1421
1422Produced 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.
1423
1424.. option:: -fblocks, -fno-blocks
1425
1426Enable the 'blocks' language feature
1427
1428.. option:: -fbootclasspath=<arg>, --bootclasspath <arg>, --bootclasspath=<arg>
1429
1430.. option:: -fborland-extensions, -fno-borland-extensions
1431
1432Accept non-standard constructs supported by the Borland compiler
1433
1434.. option:: -fbracket-depth=<arg>
1435
1436.. option:: -fbuiltin, -fno-builtin
1437
1438.. option:: -fbuiltin-module-map
1439
1440Load the clang builtins module map file.
1441
1442.. program:: clang1
1443.. option:: -fc++-static-destructors, -fno-c++-static-destructors
1444.. program:: clang
1445
1446.. option:: -fcaret-diagnostics, -fno-caret-diagnostics
1447
1448.. option:: -fcf-protection=<arg>, -fcf-protection (equivalent to -fcf-protection=full)
1449
1450Instrument control-flow architecture protection. Options: return, branch, full, none.
1451
1452.. option:: -fcf-runtime-abi=<arg>
1453
1454.. option:: -fchar8\_t, -fno-char8\_t
1455
1456Enable C++ builtin type char8\_t
1457
1458.. option:: -fclasspath=<arg>, --CLASSPATH <arg>, --CLASSPATH=<arg>, --classpath <arg>, --classpath=<arg>
1459
1460.. option:: -fcolor-diagnostics, -fno-color-diagnostics
1461
1462Enable colors in diagnostics
1463
1464.. option:: -fcommon, -fno-common
1465
1466Place uninitialized global variables in a common block
1467
1468.. option:: -fcompile-resource=<arg>, --resource <arg>, --resource=<arg>
1469
1470.. option:: -fconstant-cfstrings, -fno-constant-cfstrings
1471
1472.. option:: -fconstant-string-class=<arg>
1473
1474.. option:: -fconstexpr-backtrace-limit=<arg>
1475
1476.. option:: -fconstexpr-depth=<arg>
1477
1478.. option:: -fconstexpr-steps=<arg>
1479
1480.. option:: -fconvergent-functions
1481
1482Assume functions may be convergent
1483
1484.. option:: -fcoroutines-ts, -fno-coroutines-ts
1485
1486Enable support for the C++ Coroutines TS
1487
1488.. option:: -fcoverage-compilation-dir=<arg>
1489
1490The compilation directory to embed in the coverage mapping.
1491
1492.. option:: -fcoverage-mapping, -fno-coverage-mapping
1493
1494Generate coverage mapping to enable code coverage analysis
1495
1496.. option:: -fcoverage-prefix-map=<arg>
1497
1498remap file source paths in coverage mapping
1499
1500.. option:: -fcreate-profile
1501
1502.. option:: -fcs-profile-generate
1503
1504Generate instrumented code to collect context sensitive execution counts into default.profraw (overridden by LLVM\_PROFILE\_FILE env var)
1505
1506.. program:: clang1
1507.. option:: -fcs-profile-generate=<directory>
1508.. program:: clang
1509
1510Generate instrumented code to collect context sensitive execution counts into <directory>/default.profraw (overridden by LLVM\_PROFILE\_FILE env var)
1511
1512.. option:: -fcuda-approx-transcendentals, -fno-cuda-approx-transcendentals
1513
1514Use approximate transcendental functions
1515
1516.. option:: -fcuda-short-ptr, -fno-cuda-short-ptr
1517
1518Use 32-bit pointers for accessing const/local/shared address spaces
1519
1520.. option:: -fcxx-exceptions, -fno-cxx-exceptions
1521
1522Enable C++ exceptions
1523
1524.. option:: -fcxx-modules, -fno-cxx-modules
1525
1526.. option:: -fdata-sections, -fno-data-sections
1527
1528Place each data in its own section
1529
1530.. option:: -fdebug-compilation-dir=<arg>, -fdebug-compilation-dir <arg>
1531
1532The compilation directory to embed in the debug info
1533
1534.. option:: -fdebug-default-version=<arg>
1535
1536Default DWARF version to use, if a -g option caused DWARF debug info to be produced
1537
1538.. option:: -fdebug-info-for-profiling, -fno-debug-info-for-profiling
1539
1540Emit extra debug info to make sample profile more accurate
1541
1542.. option:: -fdebug-macro, -fno-debug-macro
1543
1544Emit macro debug information
1545
1546.. option:: -fdebug-pass-arguments
1547
1548.. option:: -fdebug-pass-structure
1549
1550.. option:: -fdebug-prefix-map=<arg>
1551
1552remap file source paths in debug info
1553
1554.. option:: -fdebug-ranges-base-address, -fno-debug-ranges-base-address
1555
1556Use DWARF base address selection entries in .debug\_ranges
1557
1558.. option:: -fdebug-types-section, -fno-debug-types-section
1559
1560Place debug types in their own section (ELF Only)
1561
1562.. option:: -fdelayed-template-parsing, -fno-delayed-template-parsing
1563
1564Parse templated function definitions at the end of the translation unit
1565
1566.. option:: -fdelete-null-pointer-checks, -fno-delete-null-pointer-checks
1567
1568Treat usage of null pointers as undefined behavior (default)
1569
1570.. option:: -fdenormal-fp-math=<arg>
1571
1572.. option:: -fdiagnostics-absolute-paths
1573
1574Print absolute paths in diagnostics
1575
1576.. option:: -fdiagnostics-color, -fno-diagnostics-color
1577
1578.. program:: clang1
1579.. option:: -fdiagnostics-color=<arg>
1580.. program:: clang
1581
1582.. option:: -fdiagnostics-hotness-threshold=<value>
1583
1584Prevent optimization remarks from being output if they do not have at least this profile count. Use 'auto' to apply the threshold from profile summary
1585
1586.. option:: -fdiagnostics-show-hotness, -fno-diagnostics-show-hotness
1587
1588Enable profile hotness information in diagnostic line
1589
1590.. option:: -fdiagnostics-show-note-include-stack, -fno-diagnostics-show-note-include-stack
1591
1592Display include stacks for diagnostic notes
1593
1594.. option:: -fdiagnostics-show-option, -fno-diagnostics-show-option
1595
1596Print option name with mappable diagnostics
1597
1598.. option:: -fdiagnostics-show-template-tree
1599
1600Print a template comparison tree for differing templates
1601
1602.. option:: -fdigraphs, -fno-digraphs
1603
1604Enable alternative token representations '<:', ':>', '<%', '%>', '%:', '%:%:' (default)
1605
1606.. option:: -fdirect-access-external-data, -fno-direct-access-external-data
1607
1608Don't use GOT indirection to reference external data symbols
1609
1610.. option:: -fdollars-in-identifiers, -fno-dollars-in-identifiers
1611
1612Allow '$' in identifiers
1613
1614.. option:: -fdouble-square-bracket-attributes, -fno-double-square-bracket-attributes
1615
1616Enable '\[\[\]\]' attributes in all C and C++ language modes
1617
1618.. option:: -fdwarf-directory-asm, -fno-dwarf-directory-asm
1619
1620.. option:: -fdwarf-exceptions
1621
1622Use DWARF style exceptions
1623
1624.. option:: -felide-constructors, -fno-elide-constructors
1625
1626.. option:: -feliminate-unused-debug-symbols, -fno-eliminate-unused-debug-symbols
1627
1628.. option:: -feliminate-unused-debug-types, -fno-eliminate-unused-debug-types
1629
1630Do not emit  debug info for defined but unused types
1631
1632.. option:: -fembed-bitcode=<option>, -fembed-bitcode (equivalent to -fembed-bitcode=all), -fembed-bitcode-marker (equivalent to -fembed-bitcode=marker)
1633
1634Embed LLVM bitcode (option: off, all, bitcode, marker)
1635
1636.. option:: -femit-all-decls
1637
1638Emit all declarations, even if unused
1639
1640.. option:: -femulated-tls, -fno-emulated-tls
1641
1642Use emutls functions to access thread\_local variables
1643
1644.. option:: -fenable-matrix
1645
1646Enable matrix data type and related builtin functions
1647
1648.. option:: -fencoding=<arg>, --encoding <arg>, --encoding=<arg>
1649
1650.. option:: -ferror-limit=<arg>
1651
1652.. option:: -fescaping-block-tail-calls, -fno-escaping-block-tail-calls
1653
1654.. option:: -fexceptions, -fno-exceptions
1655
1656Enable support for exception handling
1657
1658.. option:: -fexec-charset=<arg>
1659
1660.. option:: -fexperimental-new-constant-interpreter
1661
1662Enable the experimental new constant interpreter
1663
1664.. option:: -fextdirs=<arg>, --extdirs <arg>, --extdirs=<arg>
1665
1666.. option:: -fextend-arguments=<arg>
1667
1668Controls how scalar integer arguments are extended in calls to unprototyped and varargs functions
1669
1670.. option:: -ffast-math, -fno-fast-math
1671
1672Allow aggressive, lossy floating-point optimizations
1673
1674.. option:: -ffile-compilation-dir=<arg>
1675
1676The compilation directory to embed in the debug info and coverage mapping.
1677
1678.. option:: -ffile-prefix-map=<arg>
1679
1680remap file source paths in debug info and predefined preprocessor macros
1681
1682.. option:: -ffinite-loops, -fno-finite-loops
1683
1684Assume all loops are finite.
1685
1686.. option:: -ffinite-math-only, -fno-finite-math-only
1687
1688.. option:: -ffixed-point, -fno-fixed-point
1689
1690Enable fixed point types
1691
1692.. option:: -ffor-scope, -fno-for-scope
1693
1694.. option:: -fforce-dwarf-frame, -fno-force-dwarf-frame
1695
1696Always emit a debug frame section
1697
1698.. option:: -fforce-emit-vtables, -fno-force-emit-vtables
1699
1700Emits more virtual tables to improve devirtualization
1701
1702.. option:: -fforce-enable-int128, -fno-force-enable-int128
1703
1704Enable support for int128\_t type
1705
1706.. option:: -ffp-contract=<arg>
1707
1708Form 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.
1709
1710.. option:: -ffp-exception-behavior=<arg>
1711
1712Specifies the exception behavior of floating-point operations.
1713
1714.. option:: -ffp-model=<arg>
1715
1716Controls the semantics of floating-point calculations.
1717
1718.. option:: -ffreestanding
1719
1720Assert that the compilation takes place in a freestanding environment
1721
1722.. option:: -ffunction-sections, -fno-function-sections
1723
1724Place each function in its own section
1725
1726.. option:: -fgnu-inline-asm, -fno-gnu-inline-asm
1727
1728.. option:: -fgnu-keywords, -fno-gnu-keywords
1729
1730Allow GNU-extension keywords regardless of language standard
1731
1732.. option:: -fgnu-runtime
1733
1734Generate output compatible with the standard GNU Objective-C runtime
1735
1736.. option:: -fgnu89-inline, -fno-gnu89-inline
1737
1738Use the gnu89 inline semantics
1739
1740.. option:: -fgnuc-version=<arg>
1741
1742Sets various macros to claim compatibility with the given GCC version (default is 4.2.1)
1743
1744.. option:: -fgpu-allow-device-init, -fno-gpu-allow-device-init
1745
1746Allow device side init function in HIP (experimental)
1747
1748.. option:: -fgpu-defer-diag, -fno-gpu-defer-diag
1749
1750Defer host/device related diagnostic messages for CUDA/HIP
1751
1752.. option:: -fgpu-rdc, -fcuda-rdc, -fno-gpu-rdc
1753
1754Generate relocatable device code, also known as separate compilation mode
1755
1756.. option:: -fgpu-sanitize, -fno-gpu-sanitize
1757
1758Enable sanitizer for AMDGPU target
1759
1760.. option:: -fhip-fp32-correctly-rounded-divide-sqrt, -fno-hip-fp32-correctly-rounded-divide-sqrt
1761
1762Specify that single precision floating-point divide and sqrt used in the program source are correctly rounded (HIP device compilation only)
1763
1764.. option:: -fhip-new-launch-api, -fno-hip-new-launch-api
1765
1766Use new kernel launching API for HIP
1767
1768.. option:: -fhonor-infinities, -fhonor-infinites, -fno-honor-infinities
1769
1770.. option:: -fhonor-nans, -fno-honor-nans
1771
1772.. option:: -fhosted
1773
1774.. option:: -fignore-exceptions
1775
1776Enable support for ignoring exception handling constructs
1777
1778.. option:: -fimplicit-module-maps, -fmodule-maps, -fno-implicit-module-maps
1779
1780Implicitly search the file system for module map files.
1781
1782.. option:: -fimplicit-modules, -fno-implicit-modules
1783
1784.. option:: -finput-charset=<arg>
1785
1786Specify the default character set for source files
1787
1788.. option:: -finstrument-function-entry-bare
1789
1790Instrument function entry only, after inlining, without arguments to the instrumentation call
1791
1792.. option:: -finstrument-functions
1793
1794Generate calls to instrument function entry and exit
1795
1796.. option:: -finstrument-functions-after-inlining
1797
1798Like -finstrument-functions, but insert the calls after inlining
1799
1800.. option:: -fintegrated-as, -fno-integrated-as, -integrated-as
1801
1802Enable the integrated assembler
1803
1804.. option:: -fintegrated-cc1, -fno-integrated-cc1
1805
1806Run cc1 in-process
1807
1808.. option:: -fjump-tables, -fno-jump-tables
1809
1810Use jump tables for lowering switches
1811
1812.. option:: -fkeep-static-consts, -fno-keep-static-consts
1813
1814Keep static const variables if unused
1815
1816.. option:: -flax-vector-conversions=<arg>, -flax-vector-conversions (equivalent to -flax-vector-conversions=integer), -fno-lax-vector-conversions (equivalent to -flax-vector-conversions=none)
1817
1818Enable implicit vector bit-casts
1819
1820.. option:: -flimited-precision=<arg>
1821
1822.. option:: -flto, -fno-lto
1823
1824Enable LTO in 'full' mode
1825
1826.. option:: -flto-jobs=<arg>
1827
1828Controls the backend parallelism of -flto=thin (default of 0 means the number of threads will be derived from the number of CPUs detected)
1829
1830.. program:: clang1
1831.. option:: -flto=<arg>
1832.. program:: clang
1833
1834Set LTO mode to either 'full' or 'thin'
1835
1836.. program:: clang2
1837.. option:: -flto=auto
1838.. program:: clang
1839
1840.. program:: clang3
1841.. option:: -flto=jobserver
1842.. program:: clang
1843
1844.. option:: -fmacro-backtrace-limit=<arg>
1845
1846.. option:: -fmath-errno, -fno-math-errno
1847
1848Require math functions to indicate errors by setting errno
1849
1850.. option:: -fmax-tokens=<arg>
1851
1852Max total number of preprocessed tokens for -Wmax-tokens.
1853
1854.. option:: -fmax-type-align=<arg>
1855
1856Specify the maximum alignment to enforce on pointers lacking an explicit alignment
1857
1858.. option:: -fmemory-profile, -fno-memory-profile
1859
1860Enable heap memory profiling
1861
1862.. program:: clang1
1863.. option:: -fmemory-profile=<directory>
1864.. program:: clang
1865
1866Enable heap memory profiling and dump results into <directory>
1867
1868.. option:: -fmerge-all-constants, -fno-merge-all-constants
1869
1870Allow merging of constants
1871
1872.. option:: -fmessage-length=<arg>
1873
1874Format message diagnostics so that they fit within N columns
1875
1876.. option:: -fmodule-file-deps, -fno-module-file-deps
1877
1878.. option:: -fmodule-map-file=<file>
1879
1880Load this module map file
1881
1882.. option:: -fmodule-name=<name>, -fmodule-implementation-of <arg>
1883
1884Specify the name of the module to build
1885
1886.. option:: -fmodules, -fno-modules
1887
1888Enable the 'modules' language feature
1889
1890.. option:: -fmodules-decluse, -fno-modules-decluse
1891
1892Require declaration of modules used within a module
1893
1894.. option:: -fmodules-ignore-macro=<arg>
1895
1896Ignore the definition of the given macro when building and loading modules
1897
1898.. option:: -fmodules-search-all, -fno-modules-search-all
1899
1900Search even non-imported modules to resolve references
1901
1902.. option:: -fmodules-strict-decluse
1903
1904Like -fmodules-decluse but requires all headers to be in modules
1905
1906.. option:: -fmodules-ts
1907
1908Enable support for the C++ Modules TS
1909
1910.. option:: -fmodules-validate-input-files-content
1911
1912Validate PCM input files based on content if mtime differs
1913
1914.. option:: -fms-compatibility, -fno-ms-compatibility
1915
1916Enable full Microsoft Visual C++ compatibility
1917
1918.. option:: -fms-compatibility-version=<arg>
1919
1920Dot-separated value representing the Microsoft compiler version number to report in \_MSC\_VER (0 = don't define it (default))
1921
1922.. option:: -fms-extensions, -fno-ms-extensions
1923
1924Accept some non-standard constructs supported by the Microsoft compiler
1925
1926.. option:: -fms-memptr-rep=<arg>
1927
1928.. option:: -fms-volatile
1929
1930.. option:: -fmsc-version=<arg>
1931
1932Microsoft compiler version number to report in \_MSC\_VER (0 = don't define it (default))
1933
1934.. option:: -fmudflap
1935
1936.. option:: -fmudflapth
1937
1938.. option:: -fnested-functions
1939
1940.. option:: -fnew-alignment=<align>, -fnew-alignment <arg>
1941
1942Specifies the largest alignment guaranteed by '::operator new(size\_t)'
1943
1944.. option:: -fnext-runtime
1945
1946.. option:: -fno-builtin-<arg>
1947
1948Disable implicit builtin knowledge of a specific function
1949
1950.. option:: -fno-elide-type
1951
1952Do not elide types when printing diagnostics
1953
1954.. option:: -fno-max-type-align
1955
1956.. option:: -fno-strict-modules-decluse
1957
1958.. option:: -fno-temp-file
1959
1960Directly create compilation output files. This may lead to incorrect incremental builds if the compiler crashes
1961
1962.. option:: -fno-working-directory
1963
1964.. option:: -fno\_modules-validate-input-files-content
1965
1966.. program:: clang1
1967.. option:: -fno\_pch-validate-input-files-content
1968.. program:: clang
1969
1970.. option:: -fnoxray-link-deps
1971
1972.. option:: -fobjc-abi-version=<arg>
1973
1974.. option:: -fobjc-arc, -fno-objc-arc
1975
1976Synthesize retain and release calls for Objective-C pointers
1977
1978.. option:: -fobjc-arc-exceptions, -fno-objc-arc-exceptions
1979
1980Use EH-safe code when synthesizing retains and releases in -fobjc-arc
1981
1982.. option:: -fobjc-convert-messages-to-runtime-calls, -fno-objc-convert-messages-to-runtime-calls
1983
1984.. option:: -fobjc-disable-direct-methods-for-testing
1985
1986Ignore attribute objc\_direct so that direct methods can be tested
1987
1988.. option:: -fobjc-encode-cxx-class-template-spec, -fno-objc-encode-cxx-class-template-spec
1989
1990Fully encode c++ class template specialization
1991
1992.. option:: -fobjc-exceptions, -fno-objc-exceptions
1993
1994Enable Objective-C exceptions
1995
1996.. option:: -fobjc-infer-related-result-type, -fno-objc-infer-related-result-type
1997
1998.. option:: -fobjc-legacy-dispatch, -fno-objc-legacy-dispatch
1999
2000.. option:: -fobjc-link-runtime
2001
2002.. option:: -fobjc-nonfragile-abi, -fno-objc-nonfragile-abi
2003
2004.. option:: -fobjc-nonfragile-abi-version=<arg>
2005
2006.. option:: -fobjc-runtime=<arg>
2007
2008Specify the target Objective-C runtime kind and version
2009
2010.. option:: -fobjc-sender-dependent-dispatch
2011
2012.. option:: -fobjc-weak, -fno-objc-weak
2013
2014Enable ARC-style weak references in Objective-C
2015
2016.. option:: -foffload-lto, -fno-offload-lto
2017
2018Enable LTO in 'full' mode for offload compilation
2019
2020.. program:: clang1
2021.. option:: -foffload-lto=<arg>
2022.. program:: clang
2023
2024Set LTO mode to either 'full' or 'thin' for offload compilation
2025
2026.. option:: -fomit-frame-pointer, -fno-omit-frame-pointer
2027
2028.. option:: -fopenmp, -fno-openmp
2029
2030Parse OpenMP pragmas and generate parallel code.
2031
2032.. option:: -fopenmp-simd, -fno-openmp-simd
2033
2034Emit OpenMP code only for SIMD-based constructs.
2035
2036.. option:: -fopenmp-version=<arg>
2037
2038.. program:: clang1
2039.. option:: -fopenmp=<arg>
2040.. program:: clang
2041
2042.. option:: -foperator-arrow-depth=<arg>
2043
2044.. option:: -foperator-names, -fno-operator-names
2045
2046.. option:: -foptimization-record-file=<file>
2047
2048Specify 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.
2049
2050.. option:: -foptimization-record-passes=<regex>
2051
2052Only include passes which match a specified regular expression in the generated optimization record (by default, include all passes)
2053
2054.. option:: -foptimize-sibling-calls, -fno-optimize-sibling-calls
2055
2056.. option:: -forder-file-instrumentation
2057
2058Generate instrumented code to collect order file into default.profraw file (overridden by '=' form of option or LLVM\_PROFILE\_FILE env var)
2059
2060.. option:: -foutput-class-dir=<arg>, --output-class-directory <arg>, --output-class-directory=<arg>
2061
2062.. option:: -fpack-struct, -fno-pack-struct
2063
2064.. program:: clang1
2065.. option:: -fpack-struct=<arg>
2066.. program:: clang
2067
2068Specify the default maximum struct packing alignment
2069
2070.. option:: -fpascal-strings, -fno-pascal-strings, -mpascal-strings
2071
2072Recognize and construct Pascal-style string literals
2073
2074.. option:: -fpass-plugin=<dsopath>
2075
2076Load pass plugin from a dynamic shared object file (only with new pass manager).
2077
2078.. option:: -fpatchable-function-entry=<N,M>
2079
2080Generate M NOPs before function entry and N-M NOPs after function entry
2081
2082.. option:: -fpcc-struct-return
2083
2084Override the default ABI to return all structs on the stack
2085
2086.. option:: -fpch-codegen, -fno-pch-codegen
2087
2088Generate code for uses of this PCH that assumes an explicit object file will be built for the PCH
2089
2090.. option:: -fpch-debuginfo, -fno-pch-debuginfo
2091
2092Generate debug info for types in an object file built from this PCH and do not generate them elsewhere
2093
2094.. option:: -fpch-instantiate-templates, -fno-pch-instantiate-templates
2095
2096Instantiate templates already while building a PCH
2097
2098.. option:: -fpch-preprocess
2099
2100.. option:: -fpch-validate-input-files-content
2101
2102Validate PCH input files based on content if mtime differs
2103
2104.. option:: -fpic, -fno-pic
2105
2106.. option:: -fpie, -fno-pie
2107
2108.. option:: -fplt, -fno-plt
2109
2110.. option:: -fplugin=<dsopath>
2111
2112Load the named plugin (dynamic shared object)
2113
2114.. option:: -fprebuilt-implicit-modules, -fno-prebuilt-implicit-modules
2115
2116Look up implicit modules in the prebuilt module path
2117
2118.. option:: -fpreserve-as-comments, -fno-preserve-as-comments
2119
2120.. option:: -fproc-stat-report<arg>
2121
2122Print subprocess statistics
2123
2124.. program:: clang1
2125.. option:: -fproc-stat-report=<arg>
2126.. program:: clang
2127
2128Save subprocess statistics to the given file
2129
2130.. option:: -fprofile-arcs, -fno-profile-arcs
2131
2132.. option:: -fprofile-dir=<arg>
2133
2134.. option:: -fprofile-exclude-files=<arg>
2135
2136Instrument only functions from files where names don't match all the regexes separated by a semi-colon
2137
2138.. option:: -fprofile-filter-files=<arg>
2139
2140Instrument only functions from files where names match any regex separated by a semi-colon
2141
2142.. option:: -fprofile-generate, -fno-profile-generate
2143
2144Generate instrumented code to collect execution counts into default.profraw (overridden by LLVM\_PROFILE\_FILE env var)
2145
2146.. program:: clang1
2147.. option:: -fprofile-generate=<directory>
2148.. program:: clang
2149
2150Generate instrumented code to collect execution counts into <directory>/default.profraw (overridden by LLVM\_PROFILE\_FILE env var)
2151
2152.. option:: -fprofile-instr-generate, -fno-profile-instr-generate
2153
2154Generate instrumented code to collect execution counts into default.profraw file (overridden by '=' form of option or LLVM\_PROFILE\_FILE env var)
2155
2156.. program:: clang1
2157.. option:: -fprofile-instr-generate=<file>
2158.. program:: clang
2159
2160Generate instrumented code to collect execution counts into <file> (overridden by LLVM\_PROFILE\_FILE env var)
2161
2162.. option:: -fprofile-instr-use, -fno-profile-instr-use, -fprofile-use
2163
2164.. program:: clang1
2165.. option:: -fprofile-instr-use=<arg>
2166.. program:: clang
2167
2168Use instrumentation data for profile-guided optimization
2169
2170.. option:: -fprofile-list=<arg>
2171
2172Filename defining the list of functions/files to instrument
2173
2174.. option:: -fprofile-remapping-file=<file>
2175
2176Use the remappings described in <file> to match the profile data against names in the program
2177
2178.. option:: -fprofile-sample-accurate, -fauto-profile-accurate, -fno-profile-sample-accurate
2179
2180Specifies that the sample profile is accurate. If the sample
2181               profile is accurate, callsites without profile samples are marked
2182               as cold. Otherwise, treat callsites without profile samples as if
2183               we have no profile
2184
2185.. option:: -fprofile-sample-use, -fauto-profile, -fno-profile-sample-use
2186
2187.. program:: clang1
2188.. option:: -fprofile-sample-use=<arg>, -fauto-profile=<arg>
2189.. program:: clang
2190
2191Enable sample-based profile guided optimizations
2192
2193.. option:: -fprofile-update=<method>
2194
2195Set update method of profile counters (atomic,prefer-atomic,single)
2196
2197.. program:: clang1
2198.. option:: -fprofile-use=<pathname>
2199.. program:: clang
2200
2201Use instrumentation data for profile-guided optimization. If pathname is a directory, it reads from <pathname>/default.profdata. Otherwise, it reads from file <pathname>.
2202
2203.. option:: -fpseudo-probe-for-profiling, -fno-pseudo-probe-for-profiling
2204
2205Emit pseudo probes for sample profiling
2206
2207.. option:: -freciprocal-math, -fno-reciprocal-math
2208
2209Allow division operations to be reassociated
2210
2211.. option:: -freg-struct-return
2212
2213Override the default ABI to return small structs in registers
2214
2215.. option:: -fregister-global-dtors-with-atexit, -fno-register-global-dtors-with-atexit
2216
2217Use atexit or \_\_cxa\_atexit to register global destructors
2218
2219.. option:: -frelaxed-template-template-args, -fno-relaxed-template-template-args
2220
2221Enable C++17 relaxed template template argument matching
2222
2223.. option:: -freroll-loops, -fno-reroll-loops
2224
2225Turn on loop reroller
2226
2227.. option:: -fretain-comments-from-system-headers
2228
2229.. option:: -frewrite-imports, -fno-rewrite-imports
2230
2231.. option:: -frewrite-includes, -fno-rewrite-includes
2232
2233.. option:: -frewrite-map-file=<arg>
2234
2235.. option:: -fropi, -fno-ropi
2236
2237Generate read-only position independent code (ARM only)
2238
2239.. option:: -frounding-math, -fno-rounding-math
2240
2241.. option:: -frtti, -fno-rtti
2242
2243.. option:: -frtti-data, -fno-rtti-data
2244
2245.. option:: -frwpi, -fno-rwpi
2246
2247Generate read-write position independent code (ARM only)
2248
2249.. option:: -fsave-optimization-record, -fno-save-optimization-record
2250
2251Generate a YAML optimization record file
2252
2253.. program:: clang1
2254.. option:: -fsave-optimization-record=<format>
2255.. program:: clang
2256
2257Generate an optimization record file in a specific format
2258
2259.. option:: -fseh-exceptions
2260
2261Use SEH style exceptions
2262
2263.. option:: -fsemantic-interposition, -fno-semantic-interposition
2264
2265.. option:: -fshort-enums, -fno-short-enums
2266
2267Allocate to an enum type only as many bytes as it needs for the declared range of possible values
2268
2269.. option:: -fshort-wchar, -fno-short-wchar
2270
2271Force wchar\_t to be a short unsigned int
2272
2273.. option:: -fshow-column, -fno-show-column
2274
2275.. option:: -fshow-overloads=<arg>
2276
2277Which overload candidates to show when overload resolution fails: best\|all; defaults to all
2278
2279.. option:: -fshow-source-location, -fno-show-source-location
2280
2281.. option:: -fsignaling-math, -fno-signaling-math
2282
2283.. option:: -fsigned-bitfields
2284
2285.. option:: -fsigned-char, -fno-signed-char, --signed-char
2286
2287char is signed
2288
2289.. option:: -fsigned-zeros, -fno-signed-zeros
2290
2291.. option:: -fsized-deallocation, -fno-sized-deallocation
2292
2293Enable C++14 sized global deallocation functions
2294
2295.. option:: -fsjlj-exceptions
2296
2297Use SjLj style exceptions
2298
2299.. option:: -fslp-vectorize, -fno-slp-vectorize, -ftree-slp-vectorize
2300
2301Enable the superword-level parallelism vectorization passes
2302
2303.. option:: -fspell-checking, -fno-spell-checking
2304
2305.. option:: -fspell-checking-limit=<arg>
2306
2307.. option:: -fsplit-dwarf-inlining, -fno-split-dwarf-inlining
2308
2309Provide minimal debug info in the object/executable to facilitate online symbolication/stack traces in the absence of .dwo/.dwp files when using Split DWARF
2310
2311.. option:: -fsplit-lto-unit, -fno-split-lto-unit
2312
2313Enables splitting of the LTO unit
2314
2315.. option:: -fsplit-machine-functions, -fno-split-machine-functions
2316
2317Enable late function splitting using profile information (x86 ELF)
2318
2319.. option:: -fsplit-stack, -fno-split-stack
2320
2321Use segmented stack
2322
2323.. option:: -fstack-clash-protection, -fno-stack-clash-protection
2324
2325Enable stack clash protection
2326
2327.. option:: -fstack-protector, -fno-stack-protector
2328
2329Enable 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.
2330
2331.. option:: -fstack-protector-all
2332
2333Enable stack protectors for all functions
2334
2335.. option:: -fstack-protector-strong
2336
2337Enable 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
2338
2339.. option:: -fstack-size-section, -fno-stack-size-section
2340
2341Emit section containing metadata on function stack sizes
2342
2343.. option:: -fstack-usage
2344
2345Emit .su file containing information on function stack sizes
2346
2347.. option:: -fstandalone-debug, -fno-limit-debug-info, -fno-standalone-debug
2348
2349Emit full debug info for all types used by the program
2350
2351.. option:: -fstrict-aliasing, -fno-strict-aliasing
2352
2353.. option:: -fstrict-enums, -fno-strict-enums
2354
2355Enable optimizations based on the strict definition of an enum's value range
2356
2357.. option:: -fstrict-float-cast-overflow, -fno-strict-float-cast-overflow
2358
2359Assume that overflowing float-to-int casts are undefined (default)
2360
2361.. option:: -fstrict-overflow, -fno-strict-overflow
2362
2363.. option:: -fstrict-return, -fno-strict-return
2364
2365.. option:: -fstrict-vtable-pointers, -fno-strict-vtable-pointers
2366
2367Enable optimizations based on the strict rules for overwriting polymorphic C++ objects
2368
2369.. option:: -fstruct-path-tbaa, -fno-struct-path-tbaa
2370
2371.. option:: -fsymbol-partition=<arg>
2372
2373.. option:: -ftabstop=<arg>
2374
2375.. option:: -ftemplate-backtrace-limit=<arg>
2376
2377.. option:: -ftemplate-depth-<arg>
2378
2379.. option:: -ftemplate-depth=<arg>
2380
2381.. option:: -ftest-coverage, -fno-test-coverage
2382
2383.. option:: -fthin-link-bitcode=<arg>
2384
2385Write minimized bitcode to <file> for the ThinLTO thin link only
2386
2387.. option:: -fthinlto-index=<arg>
2388
2389Perform ThinLTO importing using provided function summary index
2390
2391.. option:: -fthreadsafe-statics, -fno-threadsafe-statics
2392
2393.. option:: -ftime-report
2394
2395.. program:: clang1
2396.. option:: -ftime-report=<arg>
2397.. program:: clang
2398
2399(For new pass manager) "per-pass": one report for each pass; "per-pass-run": one report for each pass invocation
2400
2401.. option:: -ftime-trace
2402
2403
2404Turn on time profiler. Generates JSON file based on output filename. Results
2405can be analyzed with chrome://tracing or `Speedscope App
2406<https://www.speedscope.app>`_ for flamegraph visualization.
2407
2408.. option:: -ftime-trace-granularity=<arg>
2409
2410Minimum time granularity (in microseconds) traced by time profiler
2411
2412.. option:: -ftls-model=<arg>
2413
2414.. option:: -ftrap-function=<arg>
2415
2416Issue call to specified function rather than a trap instruction
2417
2418.. option:: -ftrapping-math, -fno-trapping-math
2419
2420.. option:: -ftrapv
2421
2422Trap on integer overflow
2423
2424.. option:: -ftrapv-handler <arg>
2425
2426.. program:: clang1
2427.. option:: -ftrapv-handler=<function name>
2428.. program:: clang
2429
2430Specify the function to be called on overflow
2431
2432.. option:: -ftrigraphs, -fno-trigraphs, -trigraphs, --trigraphs
2433
2434Process trigraph sequences
2435
2436.. option:: -ftrivial-auto-var-init-stop-after=<arg>
2437
2438Stop initializing trivial automatic stack variables after the specified number of instances
2439
2440.. option:: -ftrivial-auto-var-init=<arg>
2441
2442Initialize trivial automatic stack variables: uninitialized (default) \| pattern
2443
2444.. option:: -funique-basic-block-section-names, -fno-unique-basic-block-section-names
2445
2446Use unique names for basic block sections (ELF Only)
2447
2448.. option:: -funique-internal-linkage-names, -fno-unique-internal-linkage-names
2449
2450Uniqueify Internal Linkage Symbol Names by appending the MD5 hash of the module path
2451
2452.. option:: -funique-section-names, -fno-unique-section-names
2453
2454.. option:: -funit-at-a-time, -fno-unit-at-a-time
2455
2456.. option:: -funroll-loops, -fno-unroll-loops
2457
2458Turn on loop unroller
2459
2460.. option:: -funsafe-math-optimizations, -fno-unsafe-math-optimizations
2461
2462.. option:: -funsigned-bitfields
2463
2464.. option:: -funsigned-char, -fno-unsigned-char, --unsigned-char
2465
2466.. option:: -funwind-tables, -fno-unwind-tables
2467
2468.. option:: -fuse-cxa-atexit, -fno-use-cxa-atexit
2469
2470.. option:: -fuse-init-array, -fno-use-init-array
2471
2472.. option:: -fuse-ld=<arg>
2473
2474.. option:: -fuse-line-directives, -fno-use-line-directives
2475
2476Use #line in preprocessed output
2477
2478.. option:: -fvalidate-ast-input-files-content
2479
2480Compute 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
2481
2482.. option:: -fveclib=<arg>
2483
2484Use the given vector functions library
2485
2486.. option:: -fvectorize, -fno-vectorize, -ftree-vectorize
2487
2488Enable the loop vectorization passes
2489
2490.. option:: -fverbose-asm, -dA, -fno-verbose-asm
2491
2492Generate verbose assembly output
2493
2494.. option:: -fvirtual-function-elimination, -fno-virtual-function-elimination
2495
2496Enables dead virtual function elimination optimization. Requires -flto=full
2497
2498.. option:: -fvisibility-dllexport=<arg>
2499
2500The visibility for dllexport defintions \[-fvisibility-from-dllstorageclass\]
2501
2502.. option:: -fvisibility-externs-dllimport=<arg>
2503
2504The visibility for dllimport external declarations \[-fvisibility-from-dllstorageclass\]
2505
2506.. option:: -fvisibility-externs-nodllstorageclass=<arg>
2507
2508The visibility for external declarations without an explicit DLL dllstorageclass \[-fvisibility-from-dllstorageclass\]
2509
2510.. option:: -fvisibility-from-dllstorageclass, -fno-visibility-from-dllstorageclass
2511
2512Set the visiblity of symbols in the generated code from their DLL storage class
2513
2514.. option:: -fvisibility-global-new-delete-hidden
2515
2516Give global C++ operator new and delete declarations hidden visibility
2517
2518.. option:: -fvisibility-inlines-hidden, -fno-visibility-inlines-hidden
2519
2520Give inline C++ member functions hidden visibility by default
2521
2522.. option:: -fvisibility-inlines-hidden-static-local-var, -fno-visibility-inlines-hidden-static-local-var
2523
2524When -fvisibility-inlines-hidden is enabled, static variables in inline C++ member functions will also be given hidden visibility by default
2525
2526.. option:: -fvisibility-ms-compat
2527
2528Give global types 'default' visibility and global functions and variables 'hidden' visibility by default
2529
2530.. option:: -fvisibility-nodllstorageclass=<arg>
2531
2532The visibility for defintiions without an explicit DLL export class \[-fvisibility-from-dllstorageclass\]
2533
2534.. option:: -fvisibility=<arg>
2535
2536Set the default symbol visibility for all global declarations
2537
2538.. option:: -fwarn-stack-size=<arg>
2539
2540.. option:: -fwasm-exceptions
2541
2542Use WebAssembly style exceptions
2543
2544.. option:: -fwhole-program-vtables, -fno-whole-program-vtables
2545
2546Enables whole-program vtable optimization. Requires -flto
2547
2548.. option:: -fwrapv, -fno-wrapv
2549
2550Treat signed integer overflow as two's complement
2551
2552.. option:: -fwritable-strings
2553
2554Store string literals as writable data
2555
2556.. option:: -fxl-pragma-pack, -fno-xl-pragma-pack
2557
2558Enable IBM XL #pragma pack handling
2559
2560.. option:: -fxray-always-emit-customevents, -fno-xray-always-emit-customevents
2561
2562Always emit \_\_xray\_customevent(...) calls even if the containing function is not always instrumented
2563
2564.. option:: -fxray-always-emit-typedevents, -fno-xray-always-emit-typedevents
2565
2566Always emit \_\_xray\_typedevent(...) calls even if the containing function is not always instrumented
2567
2568.. option:: -fxray-always-instrument=<arg>
2569
2570DEPRECATED: Filename defining the whitelist for imbuing the 'always instrument' XRay attribute.
2571
2572.. option:: -fxray-attr-list=<arg>
2573
2574Filename defining the list of functions/types for imbuing XRay attributes.
2575
2576.. option:: -fxray-function-groups=<arg>
2577
2578Only instrument 1 of N groups
2579
2580.. option:: -fxray-function-index, -fno-xray-function-index
2581
2582.. option:: -fxray-ignore-loops, -fno-xray-ignore-loops
2583
2584Don't instrument functions with loops unless they also meet the minimum function size
2585
2586.. option:: -fxray-instruction-threshold<arg>
2587
2588.. program:: clang1
2589.. option:: -fxray-instruction-threshold=<arg>
2590.. program:: clang
2591
2592Sets the minimum function size to instrument with XRay
2593
2594.. option:: -fxray-instrument, -fno-xray-instrument
2595
2596Generate XRay instrumentation sleds on function entry and exit
2597
2598.. option:: -fxray-instrumentation-bundle=<arg>
2599
2600Select 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'.
2601
2602.. option:: -fxray-link-deps
2603
2604Tells clang to add the link dependencies for XRay.
2605
2606.. option:: -fxray-modes=<arg>
2607
2608List of modes to link in by default into XRay instrumented binaries.
2609
2610.. option:: -fxray-never-instrument=<arg>
2611
2612DEPRECATED: Filename defining the whitelist for imbuing the 'never instrument' XRay attribute.
2613
2614.. option:: -fxray-selected-function-group=<arg>
2615
2616When using -fxray-function-groups, select which group of functions to instrument. Valid range is 0 to fxray-function-groups - 1
2617
2618.. option:: -fzero-initialized-in-bss, -fno-zero-initialized-in-bss
2619
2620.. option:: -fzvector, -fno-zvector, -mzvector
2621
2622Enable System z vector language extension
2623
2624.. option:: --gpu-bundle-output, --no-gpu-bundle-output
2625
2626Bundle output files of HIP device compilation
2627
2628.. option:: -pedantic, --pedantic, -no-pedantic, --no-pedantic
2629
2630Warn on language extensions
2631
2632.. option:: -pedantic-errors, --pedantic-errors
2633
2634OpenCL flags
2635------------
2636.. option:: -cl-denorms-are-zero
2637
2638OpenCL only. Allow denormals to be flushed to zero.
2639
2640.. option:: -cl-fast-relaxed-math
2641
2642OpenCL only. Sets -cl-finite-math-only and -cl-unsafe-math-optimizations, and defines \_\_FAST\_RELAXED\_MATH\_\_.
2643
2644.. option:: -cl-finite-math-only
2645
2646OpenCL only. Allow floating-point optimizations that assume arguments and results are not NaNs or +-Inf.
2647
2648.. option:: -cl-fp32-correctly-rounded-divide-sqrt
2649
2650OpenCL only. Specify that single precision floating-point divide and sqrt used in the program source are correctly rounded.
2651
2652.. option:: -cl-kernel-arg-info
2653
2654OpenCL only. Generate kernel argument metadata.
2655
2656.. option:: -cl-mad-enable
2657
2658OpenCL only. Allow use of less precise MAD computations in the generated binary.
2659
2660.. option:: -cl-no-signed-zeros
2661
2662OpenCL only. Allow use of less precise no signed zeros computations in the generated binary.
2663
2664.. option:: -cl-no-stdinc
2665
2666OpenCL only. Disables all standard includes containing non-native compiler types and functions.
2667
2668.. option:: -cl-opt-disable
2669
2670OpenCL only. This option disables all optimizations. By default optimizations are enabled.
2671
2672.. option:: -cl-single-precision-constant
2673
2674OpenCL only. Treat double precision floating-point constant as single precision constant.
2675
2676.. option:: -cl-std=<arg>
2677
2678OpenCL language standard to compile for.
2679
2680.. option:: -cl-strict-aliasing
2681
2682OpenCL only. This option is added for compatibility with OpenCL 1.0.
2683
2684.. option:: -cl-uniform-work-group-size
2685
2686OpenCL only. Defines that the global work-size be a multiple of the work-group size specified to clEnqueueNDRangeKernel
2687
2688.. option:: -cl-unsafe-math-optimizations
2689
2690OpenCL only. Allow unsafe floating-point optimizations.  Also implies -cl-no-signed-zeros and -cl-mad-enable.
2691
2692SYCL flags
2693----------
2694.. option:: -fsycl, -fno-sycl
2695
2696Enables SYCL kernels compilation for device
2697
2698.. option:: -sycl-std=<arg>
2699
2700SYCL language standard to compile for.
2701
2702Target-dependent compilation options
2703~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
2704.. option:: -G<size>, -G=<arg>, -msmall-data-limit=<arg>, -msmall-data-threshold=<arg>
2705
2706Put objects of at most <size> bytes into small data section (MIPS / Hexagon)
2707
2708.. option:: -ffixed-x1
2709
2710Reserve the x1 register (AArch64/RISC-V only)
2711
2712.. option:: -ffixed-x10
2713
2714Reserve the x10 register (AArch64/RISC-V only)
2715
2716.. option:: -ffixed-x11
2717
2718Reserve the x11 register (AArch64/RISC-V only)
2719
2720.. option:: -ffixed-x12
2721
2722Reserve the x12 register (AArch64/RISC-V only)
2723
2724.. option:: -ffixed-x13
2725
2726Reserve the x13 register (AArch64/RISC-V only)
2727
2728.. option:: -ffixed-x14
2729
2730Reserve the x14 register (AArch64/RISC-V only)
2731
2732.. option:: -ffixed-x15
2733
2734Reserve the x15 register (AArch64/RISC-V only)
2735
2736.. option:: -ffixed-x16
2737
2738Reserve the x16 register (AArch64/RISC-V only)
2739
2740.. option:: -ffixed-x17
2741
2742Reserve the x17 register (AArch64/RISC-V only)
2743
2744.. option:: -ffixed-x18
2745
2746Reserve the x18 register (AArch64/RISC-V only)
2747
2748.. option:: -ffixed-x19
2749
2750Reserve the x19 register (AArch64/RISC-V only)
2751
2752.. option:: -ffixed-x2
2753
2754Reserve the x2 register (AArch64/RISC-V only)
2755
2756.. option:: -ffixed-x20
2757
2758Reserve the x20 register (AArch64/RISC-V only)
2759
2760.. option:: -ffixed-x21
2761
2762Reserve the x21 register (AArch64/RISC-V only)
2763
2764.. option:: -ffixed-x22
2765
2766Reserve the x22 register (AArch64/RISC-V only)
2767
2768.. option:: -ffixed-x23
2769
2770Reserve the x23 register (AArch64/RISC-V only)
2771
2772.. option:: -ffixed-x24
2773
2774Reserve the x24 register (AArch64/RISC-V only)
2775
2776.. option:: -ffixed-x25
2777
2778Reserve the x25 register (AArch64/RISC-V only)
2779
2780.. option:: -ffixed-x26
2781
2782Reserve the x26 register (AArch64/RISC-V only)
2783
2784.. option:: -ffixed-x27
2785
2786Reserve the x27 register (AArch64/RISC-V only)
2787
2788.. option:: -ffixed-x28
2789
2790Reserve the x28 register (AArch64/RISC-V only)
2791
2792.. option:: -ffixed-x29
2793
2794Reserve the x29 register (AArch64/RISC-V only)
2795
2796.. option:: -ffixed-x3
2797
2798Reserve the x3 register (AArch64/RISC-V only)
2799
2800.. option:: -ffixed-x30
2801
2802Reserve the x30 register (AArch64/RISC-V only)
2803
2804.. option:: -ffixed-x31
2805
2806Reserve the x31 register (AArch64/RISC-V only)
2807
2808.. option:: -ffixed-x4
2809
2810Reserve the x4 register (AArch64/RISC-V only)
2811
2812.. option:: -ffixed-x5
2813
2814Reserve the x5 register (AArch64/RISC-V only)
2815
2816.. option:: -ffixed-x6
2817
2818Reserve the x6 register (AArch64/RISC-V only)
2819
2820.. option:: -ffixed-x7
2821
2822Reserve the x7 register (AArch64/RISC-V only)
2823
2824.. option:: -ffixed-x8
2825
2826Reserve the x8 register (AArch64/RISC-V only)
2827
2828.. option:: -ffixed-x9
2829
2830Reserve the x9 register (AArch64/RISC-V only)
2831
2832.. option:: -m16
2833
2834.. option:: -m32
2835
2836.. option:: -m64
2837
2838.. option:: -mabi=<arg>
2839
2840.. program:: clang1
2841.. option:: -mabi=vec-default
2842.. program:: clang
2843
2844Enable the default Altivec ABI on AIX (AIX only). Uses only volatile vector registers.
2845
2846.. program:: clang2
2847.. option:: -mabi=vec-extabi
2848.. program:: clang
2849
2850Enable the extended Altivec ABI on AIX (AIX only). Uses volatile and nonvolatile vector registers
2851
2852.. option:: -maix-struct-return
2853
2854Return all structs in memory (PPC32 only)
2855
2856.. option:: -malign-branch-boundary=<arg>
2857
2858Specify the boundary's size to align branches
2859
2860.. option:: -malign-branch=<arg1>,<arg2>...
2861
2862Specify types of branches to align
2863
2864.. option:: -malign-double
2865
2866Align doubles to two words in structs (x86 only)
2867
2868.. option:: -mamdgpu-ieee, -mno-amdgpu-ieee
2869
2870Sets 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)
2871
2872.. option:: -march=<arg>
2873
2874.. option:: -masm=<arg>
2875
2876.. option:: -mbackchain, -mno-backchain
2877
2878Link stack frames through backchain on System Z
2879
2880.. option:: -mbranches-within-32B-boundaries
2881
2882Align selected branches (fused, jcc, jmp) within 32-byte boundary
2883
2884.. option:: -mcmodel=<arg>, -mcmodel=medany (equivalent to -mcmodel=medium), -mcmodel=medlow (equivalent to -mcmodel=small)
2885
2886.. option:: -mcode-object-v3, -mno-code-object-v3
2887
2888Legacy option to specify code object ABI V3 (AMDGPU only)
2889
2890.. option:: -mcode-object-version=<version>
2891
2892Specify code object ABI version. Defaults to 3. (AMDGPU only)
2893
2894.. option:: -mconsole<arg>
2895
2896.. program:: clang1
2897.. 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)
2898.. program:: clang
2899
2900.. option:: -mcrc, -mno-crc
2901
2902Allow use of CRC instructions (ARM/Mips only)
2903
2904.. option:: -mdefault-build-attributes<arg>, -mno-default-build-attributes<arg>
2905
2906.. option:: -mdll<arg>
2907
2908.. option:: -mdouble=<arg>
2909
2910Force double to be 32 bits or 64 bits
2911
2912.. option:: -mdynamic-no-pic<arg>
2913
2914.. option:: -meabi <arg>
2915
2916Set EABI type, e.g. 4, 5 or gnu (default depends on triple)
2917
2918.. option:: -menable-experimental-extensions
2919
2920Enable use of experimental RISC-V extensions.
2921
2922.. option:: -mfentry
2923
2924Insert calls to fentry at function entry (x86/SystemZ only)
2925
2926.. option:: -mfloat-abi=<arg>
2927
2928.. option:: -mfpmath=<arg>
2929
2930.. option:: -mfpu=<arg>
2931
2932.. option:: -mglobal-merge, -mno-global-merge
2933
2934Enable merging of globals
2935
2936.. option:: -mhard-float
2937
2938.. option:: -mhwdiv=<arg>, --mhwdiv <arg>, --mhwdiv=<arg>
2939
2940.. option:: -mhwmult=<arg>
2941
2942.. option:: -miamcu, -mno-iamcu
2943
2944Use Intel MCU ABI
2945
2946.. option:: -mignore-xcoff-visibility
2947
2948Not emit the visibility attribute for asm in AIX OS or give all symbols 'unspecified' visibility in XCOFF object file
2949
2950.. option:: -mimplicit-float, -mno-implicit-float
2951
2952.. option:: -mimplicit-it=<arg>
2953
2954.. option:: -mincremental-linker-compatible, -mno-incremental-linker-compatible
2955
2956(integrated-as) Emit an object file which can be used with an incremental linker
2957
2958.. option:: -miphoneos-version-min=<arg>, -mios-version-min=<arg>
2959
2960.. option:: -mkernel
2961
2962.. option:: -mlong-calls, -mno-long-calls
2963
2964Generate branches with extended addressability, usually via indirect jumps.
2965
2966.. option:: -mlvi-cfi, -mno-lvi-cfi
2967
2968Enable only control-flow mitigations for Load Value Injection (LVI)
2969
2970.. option:: -mlvi-hardening, -mno-lvi-hardening
2971
2972Enable all mitigations for Load Value Injection (LVI)
2973
2974.. option:: -mmacosx-version-min=<arg>, -mmacos-version-min=<arg>
2975
2976Set Mac OS X deployment target
2977
2978.. option:: -mmcu=<arg>
2979
2980.. option:: -mms-bitfields, -mno-ms-bitfields
2981
2982Set the default structure layout to be compatible with the Microsoft compiler standard
2983
2984.. option:: -mnop-mcount
2985
2986Generate mcount/\_\_fentry\_\_ calls as nops. To activate they need to be patched in.
2987
2988.. option:: -momit-leaf-frame-pointer, -mno-omit-leaf-frame-pointer
2989
2990Omit frame pointer setup for leaf functions
2991
2992.. option:: -moslib=<arg>
2993
2994.. option:: -mpacked-stack, -mno-packed-stack
2995
2996Use packed stack layout (SystemZ only).
2997
2998.. option:: -mpad-max-prefix-size=<arg>
2999
3000Specify maximum number of prefixes to use for padding
3001
3002.. option:: -mprefer-vector-width=<arg>
3003
3004Specifies preferred vector width for auto-vectorization. Defaults to 'none' which allows target specific decisions.
3005
3006.. option:: -mqdsp6-compat
3007
3008Enable hexagon-qdsp6 backward compatibility
3009
3010.. option:: -mrecip
3011
3012.. program:: clang1
3013.. option:: -mrecip=<arg1>,<arg2>...
3014.. program:: clang
3015
3016.. option:: -mrecord-mcount
3017
3018Generate a \_\_mcount\_loc section entry for each \_\_fentry\_\_ call.
3019
3020.. option:: -mred-zone, -mno-red-zone
3021
3022.. option:: -mregparm=<arg>
3023
3024.. option:: -mrelax, -mno-relax
3025
3026Enable linker relaxation
3027
3028.. option:: -mrelax-all, -mno-relax-all
3029
3030(integrated-as) Relax all machine instructions
3031
3032.. option:: -mretpoline, -mno-retpoline
3033
3034.. option:: -mrtd, -mno-rtd
3035
3036Make StdCall calling convention the default
3037
3038.. option:: -mseses, -mno-seses
3039
3040Enable speculative execution side effect suppression (SESES). Includes LVI control flow integrity mitigations
3041
3042.. option:: -msign-return-address=<arg>
3043
3044Select return address signing scope
3045
3046.. option:: -msim
3047
3048.. option:: -msoft-float, -mno-soft-float
3049
3050Use software floating point
3051
3052.. option:: -mspeculative-load-hardening, -mno-speculative-load-hardening
3053
3054.. option:: -mstack-alignment=<arg>
3055
3056Set the stack alignment
3057
3058.. option:: -mstack-arg-probe, -mno-stack-arg-probe
3059
3060Enable stack probes
3061
3062.. option:: -mstack-probe-size=<arg>
3063
3064Set the stack probe size
3065
3066.. option:: -mstack-protector-guard-offset=<arg>
3067
3068Use the given offset for addressing the stack-protector guard
3069
3070.. option:: -mstack-protector-guard-reg=<arg>
3071
3072Use the given reg for addressing the stack-protector guard
3073
3074.. option:: -mstack-protector-guard=<arg>
3075
3076Use the given guard (global, tls) for addressing the stack-protector guard
3077
3078.. option:: -mstackrealign, -mno-stackrealign
3079
3080Force realign the stack at entry to every function
3081
3082.. option:: -msvr4-struct-return
3083
3084Return small structs in registers (PPC32 only)
3085
3086.. option:: -mthread-model <arg>
3087
3088The thread model to use, e.g. posix, single (posix by default)
3089
3090.. option:: -mthreads<arg>
3091
3092.. option:: -mthumb, -mno-thumb
3093
3094.. option:: -mtls-direct-seg-refs, -mno-tls-direct-seg-refs
3095
3096Enable direct TLS access through segment registers (default)
3097
3098.. option:: -mtls-size=<arg>
3099
3100Specify 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)
3101
3102.. program:: clang1
3103.. option:: -mtune=<arg>
3104.. program:: clang
3105
3106Only supported on X86 and RISC-V. Otherwise accepted for compatibility with GCC.
3107
3108.. option:: -mtvos-version-min=<arg>, -mappletvos-version-min=<arg>
3109
3110.. option:: -municode<arg>
3111
3112.. option:: -munsafe-fp-atomics, -mno-unsafe-fp-atomics
3113
3114Enable unsafe floating point atomic instructions (AMDGPU only)
3115
3116.. option:: -mvx, -mno-vx
3117
3118.. option:: -mwarn-nonportable-cfstrings, -mno-warn-nonportable-cfstrings
3119
3120.. option:: -mwatchos-version-min=<arg>
3121
3122.. option:: -mwavefrontsize64, -mno-wavefrontsize64
3123
3124Specify wavefront size 64 mode (AMDGPU only)
3125
3126.. option:: -mwindows<arg>
3127
3128.. option:: -mx32
3129
3130AARCH64
3131-------
3132.. option:: -fcall-saved-x10
3133
3134Make the x10 register call-saved (AArch64 only)
3135
3136.. option:: -fcall-saved-x11
3137
3138Make the x11 register call-saved (AArch64 only)
3139
3140.. option:: -fcall-saved-x12
3141
3142Make the x12 register call-saved (AArch64 only)
3143
3144.. option:: -fcall-saved-x13
3145
3146Make the x13 register call-saved (AArch64 only)
3147
3148.. option:: -fcall-saved-x14
3149
3150Make the x14 register call-saved (AArch64 only)
3151
3152.. option:: -fcall-saved-x15
3153
3154Make the x15 register call-saved (AArch64 only)
3155
3156.. option:: -fcall-saved-x18
3157
3158Make the x18 register call-saved (AArch64 only)
3159
3160.. option:: -fcall-saved-x8
3161
3162Make the x8 register call-saved (AArch64 only)
3163
3164.. option:: -fcall-saved-x9
3165
3166Make the x9 register call-saved (AArch64 only)
3167
3168.. option:: -mfix-cortex-a53-835769, -mno-fix-cortex-a53-835769
3169
3170Workaround Cortex-A53 erratum 835769 (AArch64 only)
3171
3172.. option:: -mgeneral-regs-only
3173
3174Generate code which only uses the general purpose registers (AArch64 only)
3175
3176.. option:: -mmark-bti-property
3177
3178Add .note.gnu.property with BTI to assembly files (AArch64 only)
3179
3180.. option:: -msve-vector-bits=<arg>
3181
3182Specify the size in bits of an SVE vector register. Defaults to the vector length agnostic value of "scalable". (AArch64 only)
3183
3184AMDGPU
3185------
3186.. option:: -mcumode, -mno-cumode
3187
3188Specify CU wavefront execution mode (AMDGPU only)
3189
3190.. option:: -mtgsplit, -mno-tgsplit
3191
3192Enable threadgroup split execution mode (AMDGPU only)
3193
3194ARM
3195---
3196.. option:: -faapcs-bitfield-load
3197
3198Follows the AAPCS standard that all volatile bit-field write generates at least one load. (ARM only).
3199
3200.. option:: -faapcs-bitfield-width, -fno-aapcs-bitfield-width
3201
3202Follow the AAPCS standard requirement stating that volatile bit-field width is dictated by the field container type. (ARM only).
3203
3204.. option:: -ffixed-r9
3205
3206Reserve the r9 register (ARM only)
3207
3208.. option:: -mcmse
3209
3210Allow use of CMSE (Armv8-M Security Extensions)
3211
3212.. option:: -mexecute-only, -mno-execute-only, -mpure-code
3213
3214Disallow generation of data access to code sections (ARM only)
3215
3216.. option:: -mno-movt
3217
3218Disallow use of movt/movw pairs (ARM only)
3219
3220.. option:: -mno-neg-immediates
3221
3222Disallow converting instructions with negative immediates to their negation or inversion.
3223
3224.. option:: -mnocrc
3225
3226Disallow use of CRC instructions (ARM only)
3227
3228.. option:: -mrestrict-it, -mno-restrict-it
3229
3230Disallow generation of deprecated IT blocks for ARMv8. It is on by default for ARMv8 Thumb mode.
3231
3232.. option:: -mtp=<arg>
3233
3234Thread pointer access method (AArch32/AArch64 only)
3235
3236.. option:: -munaligned-access, -mno-unaligned-access
3237
3238Allow memory accesses to be unaligned (AArch32/AArch64 only)
3239
3240Hexagon
3241-------
3242.. option:: -mieee-rnd-near
3243
3244.. option:: -mmemops, -mno-memops
3245
3246Enable generation of memop instructions
3247
3248.. option:: -mnvj, -mno-nvj
3249
3250Enable generation of new-value jumps
3251
3252.. option:: -mnvs, -mno-nvs
3253
3254Enable generation of new-value stores
3255
3256.. option:: -mpackets, -mno-packets
3257
3258Enable generation of instruction packets
3259
3260Hexagon
3261-------
3262.. option:: -mhvx, -mno-hvx
3263
3264Enable Hexagon Vector eXtensions
3265
3266.. option:: -mhvx-length=<arg>
3267
3268Set Hexagon Vector Length
3269
3270.. program:: clang1
3271.. option:: -mhvx=<arg>
3272.. program:: clang
3273
3274Enable Hexagon Vector eXtensions
3275
3276M68k
3277----
3278.. option:: -ffixed-a0
3279
3280Reserve the a0 register (M68k only)
3281
3282.. option:: -ffixed-a1
3283
3284Reserve the a1 register (M68k only)
3285
3286.. option:: -ffixed-a2
3287
3288Reserve the a2 register (M68k only)
3289
3290.. option:: -ffixed-a3
3291
3292Reserve the a3 register (M68k only)
3293
3294.. option:: -ffixed-a4
3295
3296Reserve the a4 register (M68k only)
3297
3298.. option:: -ffixed-a5
3299
3300Reserve the a5 register (M68k only)
3301
3302.. option:: -ffixed-a6
3303
3304Reserve the a6 register (M68k only)
3305
3306.. option:: -ffixed-d0
3307
3308Reserve the d0 register (M68k only)
3309
3310.. option:: -ffixed-d1
3311
3312Reserve the d1 register (M68k only)
3313
3314.. option:: -ffixed-d2
3315
3316Reserve the d2 register (M68k only)
3317
3318.. option:: -ffixed-d3
3319
3320Reserve the d3 register (M68k only)
3321
3322.. option:: -ffixed-d4
3323
3324Reserve the d4 register (M68k only)
3325
3326.. option:: -ffixed-d5
3327
3328Reserve the d5 register (M68k only)
3329
3330.. option:: -ffixed-d6
3331
3332Reserve the d6 register (M68k only)
3333
3334.. option:: -ffixed-d7
3335
3336Reserve the d7 register (M68k only)
3337
3338.. option:: -m68000
3339
3340.. option:: -m68010
3341
3342.. option:: -m68020
3343
3344.. option:: -m68030
3345
3346.. option:: -m68040
3347
3348.. option:: -m68060
3349
3350MIPS
3351----
3352.. option:: -mabicalls, -mno-abicalls
3353
3354Enable SVR4-style position-independent code (Mips only)
3355
3356.. option:: -mabs=<arg>
3357
3358.. option:: -mcheck-zero-division, -mno-check-zero-division
3359
3360.. option:: -mcompact-branches=<arg>
3361
3362.. option:: -mdouble-float
3363
3364.. option:: -mdsp, -mno-dsp
3365
3366.. option:: -mdspr2, -mno-dspr2
3367
3368.. option:: -membedded-data, -mno-embedded-data
3369
3370Place constants in the .rodata section instead of the .sdata section even if they meet the -G <size> threshold (MIPS)
3371
3372.. option:: -mextern-sdata, -mno-extern-sdata
3373
3374Assume that externally defined data is in the small data if it meets the -G <size> threshold (MIPS)
3375
3376.. option:: -mfp32
3377
3378Use 32-bit floating point registers (MIPS only)
3379
3380.. option:: -mfp64
3381
3382Use 64-bit floating point registers (MIPS only)
3383
3384.. option:: -mginv, -mno-ginv
3385
3386.. option:: -mgpopt, -mno-gpopt
3387
3388Use GP relative accesses for symbols known to be in a small data section (MIPS)
3389
3390.. option:: -mindirect-jump=<arg>
3391
3392Change indirect jump instructions to inhibit speculation
3393
3394.. option:: -mips16
3395
3396.. option:: -mldc1-sdc1, -mno-ldc1-sdc1
3397
3398.. option:: -mlocal-sdata, -mno-local-sdata
3399
3400Extend the -G behaviour to object local data (MIPS)
3401
3402.. option:: -mmadd4, -mno-madd4
3403
3404Enable the generation of 4-operand madd.s, madd.d and related instructions.
3405
3406.. option:: -mmicromips, -mno-micromips
3407
3408.. option:: -mmsa, -mno-msa
3409
3410Enable MSA ASE (MIPS only)
3411
3412.. option:: -mmt, -mno-mt
3413
3414Enable MT ASE (MIPS only)
3415
3416.. option:: -mnan=<arg>
3417
3418.. option:: -mno-mips16
3419
3420.. option:: -msingle-float
3421
3422.. option:: -mvirt, -mno-virt
3423
3424.. option:: -mxgot, -mno-xgot
3425
3426PowerPC
3427-------
3428.. option:: -maltivec, -mno-altivec
3429
3430.. option:: -mcmpb, -mno-cmpb
3431
3432.. option:: -mcrbits, -mno-crbits
3433
3434.. option:: -mcrypto, -mno-crypto
3435
3436.. option:: -mdirect-move, -mno-direct-move
3437
3438.. option:: -mefpu2
3439
3440.. option:: -mfloat128, -mno-float128
3441
3442.. option:: -mfprnd, -mno-fprnd
3443
3444.. option:: -mhtm, -mno-htm
3445
3446.. option:: -minvariant-function-descriptors, -mno-invariant-function-descriptors
3447
3448.. option:: -misel, -mno-isel
3449
3450.. option:: -mlongcall, -mno-longcall
3451
3452.. option:: -mmfocrf, -mmfcrf, -mno-mfocrf
3453
3454.. option:: -mmma, -mno-mma
3455
3456.. option:: -mpaired-vector-memops, -mno-paired-vector-memops
3457
3458.. option:: -mpcrel, -mno-pcrel
3459
3460.. option:: -mpopcntd, -mno-popcntd
3461
3462.. option:: -mpower10-vector, -mno-power10-vector
3463
3464.. option:: -mpower8-vector, -mno-power8-vector
3465
3466.. option:: -mpower9-vector, -mno-power9-vector
3467
3468.. option:: -mprefixed, -mno-prefixed
3469
3470.. option:: -mprivileged
3471
3472.. option:: -mrop-protect
3473
3474.. option:: -msecure-plt
3475
3476.. option:: -mspe, -mno-spe
3477
3478.. option:: -mvsx, -mno-vsx
3479
3480WebAssembly
3481-----------
3482.. option:: -matomics, -mno-atomics
3483
3484.. option:: -mbulk-memory, -mno-bulk-memory
3485
3486.. option:: -mexception-handling, -mno-exception-handling
3487
3488.. option:: -mmultivalue, -mno-multivalue
3489
3490.. option:: -mmutable-globals, -mno-mutable-globals
3491
3492.. option:: -mnontrapping-fptoint, -mno-nontrapping-fptoint
3493
3494.. option:: -mreference-types, -mno-reference-types
3495
3496.. option:: -msign-ext, -mno-sign-ext
3497
3498.. option:: -msimd128, -mno-simd128
3499
3500.. option:: -mtail-call, -mno-tail-call
3501
3502WebAssembly Driver
3503------------------
3504.. option:: -mexec-model=<arg>
3505
3506Execution model (WebAssembly only)
3507
3508X86
3509---
3510.. option:: -m3dnow, -mno-3dnow
3511
3512.. option:: -m3dnowa, -mno-3dnowa
3513
3514.. option:: -madx, -mno-adx
3515
3516.. option:: -maes, -mno-aes
3517
3518.. option:: -mamx-bf16, -mno-amx-bf16
3519
3520.. option:: -mamx-int8, -mno-amx-int8
3521
3522.. option:: -mamx-tile, -mno-amx-tile
3523
3524.. option:: -mavx, -mno-avx
3525
3526.. option:: -mavx2, -mno-avx2
3527
3528.. option:: -mavx512bf16, -mno-avx512bf16
3529
3530.. option:: -mavx512bitalg, -mno-avx512bitalg
3531
3532.. option:: -mavx512bw, -mno-avx512bw
3533
3534.. option:: -mavx512cd, -mno-avx512cd
3535
3536.. option:: -mavx512dq, -mno-avx512dq
3537
3538.. option:: -mavx512er, -mno-avx512er
3539
3540.. option:: -mavx512f, -mno-avx512f
3541
3542.. option:: -mavx512ifma, -mno-avx512ifma
3543
3544.. option:: -mavx512pf, -mno-avx512pf
3545
3546.. option:: -mavx512vbmi, -mno-avx512vbmi
3547
3548.. option:: -mavx512vbmi2, -mno-avx512vbmi2
3549
3550.. option:: -mavx512vl, -mno-avx512vl
3551
3552.. option:: -mavx512vnni, -mno-avx512vnni
3553
3554.. option:: -mavx512vp2intersect, -mno-avx512vp2intersect
3555
3556.. option:: -mavx512vpopcntdq, -mno-avx512vpopcntdq
3557
3558.. option:: -mavxvnni, -mno-avxvnni
3559
3560.. option:: -mbmi, -mno-bmi
3561
3562.. option:: -mbmi2, -mno-bmi2
3563
3564.. option:: -mcldemote, -mno-cldemote
3565
3566.. option:: -mclflushopt, -mno-clflushopt
3567
3568.. option:: -mclwb, -mno-clwb
3569
3570.. option:: -mclzero, -mno-clzero
3571
3572.. option:: -mcx16, -mno-cx16
3573
3574.. option:: -menqcmd, -mno-enqcmd
3575
3576.. option:: -mf16c, -mno-f16c
3577
3578.. option:: -mfma, -mno-fma
3579
3580.. option:: -mfma4, -mno-fma4
3581
3582.. option:: -mfsgsbase, -mno-fsgsbase
3583
3584.. option:: -mfxsr, -mno-fxsr
3585
3586.. option:: -mgfni, -mno-gfni
3587
3588.. option:: -mhreset, -mno-hreset
3589
3590.. option:: -minvpcid, -mno-invpcid
3591
3592.. option:: -mkl, -mno-kl
3593
3594.. option:: -mlwp, -mno-lwp
3595
3596.. option:: -mlzcnt, -mno-lzcnt
3597
3598.. option:: -mmmx, -mno-mmx
3599
3600.. option:: -mmovbe, -mno-movbe
3601
3602.. option:: -mmovdir64b, -mno-movdir64b
3603
3604.. option:: -mmovdiri, -mno-movdiri
3605
3606.. option:: -mmwaitx, -mno-mwaitx
3607
3608.. option:: -mpclmul, -mno-pclmul
3609
3610.. option:: -mpconfig, -mno-pconfig
3611
3612.. option:: -mpku, -mno-pku
3613
3614.. option:: -mpopcnt, -mno-popcnt
3615
3616.. option:: -mprefetchwt1, -mno-prefetchwt1
3617
3618.. option:: -mprfchw, -mno-prfchw
3619
3620.. option:: -mptwrite, -mno-ptwrite
3621
3622.. option:: -mrdpid, -mno-rdpid
3623
3624.. option:: -mrdrnd, -mno-rdrnd
3625
3626.. option:: -mrdseed, -mno-rdseed
3627
3628.. option:: -mretpoline-external-thunk, -mno-retpoline-external-thunk
3629
3630.. option:: -mrtm, -mno-rtm
3631
3632.. option:: -msahf, -mno-sahf
3633
3634.. option:: -mserialize, -mno-serialize
3635
3636.. option:: -msgx, -mno-sgx
3637
3638.. option:: -msha, -mno-sha
3639
3640.. option:: -mshstk, -mno-shstk
3641
3642.. option:: -msse, -mno-sse
3643
3644.. option:: -msse2, -mno-sse2
3645
3646.. option:: -msse3, -mno-sse3
3647
3648.. option:: -msse4.1, -mno-sse4.1
3649
3650.. program:: clang1
3651.. option:: -msse4.2, -mno-sse4.2, -msse4
3652.. program:: clang
3653
3654.. option:: -msse4a, -mno-sse4a
3655
3656.. option:: -mssse3, -mno-ssse3
3657
3658.. option:: -mtbm, -mno-tbm
3659
3660.. option:: -mtsxldtrk, -mno-tsxldtrk
3661
3662.. option:: -muintr, -mno-uintr
3663
3664.. option:: -mvaes, -mno-vaes
3665
3666.. option:: -mvpclmulqdq, -mno-vpclmulqdq
3667
3668.. option:: -mvzeroupper, -mno-vzeroupper
3669
3670.. option:: -mwaitpkg, -mno-waitpkg
3671
3672.. option:: -mwbnoinvd, -mno-wbnoinvd
3673
3674.. option:: -mwidekl, -mno-widekl
3675
3676.. option:: -mx87, -m80387, -mno-x87
3677
3678.. option:: -mxop, -mno-xop
3679
3680.. option:: -mxsave, -mno-xsave
3681
3682.. option:: -mxsavec, -mno-xsavec
3683
3684.. option:: -mxsaveopt, -mno-xsaveopt
3685
3686.. option:: -mxsaves, -mno-xsaves
3687
3688RISCV
3689-----
3690.. option:: -msave-restore, -mno-save-restore
3691
3692Enable using library calls for save and restore
3693
3694Long double flags
3695-----------------
3696Selects the long double implementation
3697
3698.. option:: -mlong-double-128
3699
3700Force long double to be 128 bits
3701
3702.. option:: -mlong-double-64
3703
3704Force long double to be 64 bits
3705
3706.. option:: -mlong-double-80
3707
3708Force long double to be 80 bits, padded to 128 bits for storage
3709
3710Optimization level
3711~~~~~~~~~~~~~~~~~~
3712
3713Flags controlling how much optimization should be performed.
3714
3715.. option:: -O<arg>, -O (equivalent to -O1), --optimize, --optimize=<arg>
3716
3717.. option:: -Ofast<arg>
3718
3719Debug information generation
3720~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3721
3722Flags controlling how much and what kind of debug information should be
3723generated.
3724
3725Kind and level of debug information
3726-----------------------------------
3727.. option:: -g, --debug, --debug=<arg>
3728
3729Generate source-level debug information
3730
3731.. option:: -gdwarf
3732
3733Generate source-level debug information with the default dwarf version
3734
3735.. option:: -gdwarf-2
3736
3737Generate source-level debug information with dwarf version 2
3738
3739.. option:: -gdwarf-3
3740
3741Generate source-level debug information with dwarf version 3
3742
3743.. option:: -gdwarf-4
3744
3745Generate source-level debug information with dwarf version 4
3746
3747.. option:: -gdwarf-5
3748
3749Generate source-level debug information with dwarf version 5
3750
3751.. option:: -gdwarf32
3752
3753Enables DWARF32 format for ELF binaries, if debug information emission is enabled.
3754
3755.. option:: -gdwarf64
3756
3757Enables DWARF64 format for ELF binaries, if debug information emission is enabled.
3758
3759.. option:: -gfull
3760
3761.. option:: -ginline-line-tables, -gno-inline-line-tables
3762
3763.. option:: -gused
3764
3765Debug level
3766___________
3767.. option:: -g0
3768
3769.. option:: -g2
3770
3771.. option:: -g3
3772
3773.. option:: -ggdb0
3774
3775.. option:: -ggdb1
3776
3777.. option:: -ggdb2
3778
3779.. option:: -ggdb3
3780
3781.. option:: -gline-directives-only
3782
3783Emit debug line info directives only
3784
3785.. option:: -gline-tables-only, -g1, -gmlt
3786
3787Emit debug line number tables only
3788
3789.. option:: -gmodules
3790
3791Generate debug info with external references to clang modules or precompiled headers
3792
3793Debugger to tune debug information for
3794______________________________________
3795.. option:: -gdbx
3796
3797.. option:: -ggdb
3798
3799.. option:: -glldb
3800
3801.. option:: -gsce
3802
3803Debug information flags
3804-----------------------
3805.. option:: -gcolumn-info, -gno-column-info
3806
3807.. option:: -gdwarf-aranges
3808
3809.. option:: -gembed-source, -gno-embed-source
3810
3811Embed source text in DWARF debug sections
3812
3813.. option:: -ggnu-pubnames, -gno-gnu-pubnames
3814
3815.. option:: -gpubnames, -gno-pubnames
3816
3817.. option:: -grecord-command-line, -gno-record-command-line, -grecord-gcc-switches
3818
3819.. option:: -gsplit-dwarf, -gno-split-dwarf
3820
3821.. program:: clang1
3822.. option:: -gsplit-dwarf=<arg>
3823.. program:: clang
3824
3825Set DWARF fission mode to either 'split' or 'single'
3826
3827.. option:: -gstrict-dwarf, -gno-strict-dwarf
3828
3829.. option:: -gz=<arg>, -gz (equivalent to -gz=zlib)
3830
3831DWARF debug sections compression type
3832
3833Static analyzer flags
3834=====================
3835
3836Flags controlling the behavior of the Clang Static Analyzer.
3837
3838.. option:: -Xanalyzer <arg>
3839
3840Pass <arg> to the static analyzer
3841
3842Fortran compilation flags
3843=========================
3844
3845Flags that will be passed onto the ``gfortran`` compiler when Clang is given
3846a Fortran input.
3847
3848.. option:: -A<arg>, --assert <arg>, --assert=<arg>
3849
3850.. option:: -A-<arg>
3851
3852.. option:: -faggressive-function-elimination, -fno-aggressive-function-elimination
3853
3854.. option:: -falign-commons, -fno-align-commons
3855
3856.. option:: -fall-intrinsics, -fno-all-intrinsics
3857
3858.. option:: -fautomatic, -fno-automatic
3859
3860.. option:: -fbacktrace, -fno-backtrace
3861
3862.. option:: -fblas-matmul-limit=<arg>
3863
3864.. option:: -fbounds-check, -fno-bounds-check
3865
3866.. option:: -fcheck-array-temporaries, -fno-check-array-temporaries
3867
3868.. option:: -fcheck=<arg>
3869
3870.. option:: -fcoarray=<arg>
3871
3872.. option:: -fconvert=<arg>
3873
3874.. option:: -fcray-pointer, -fno-cray-pointer
3875
3876.. option:: -fd-lines-as-code, -fno-d-lines-as-code
3877
3878.. option:: -fd-lines-as-comments, -fno-d-lines-as-comments
3879
3880.. option:: -fdollar-ok, -fno-dollar-ok
3881
3882.. option:: -fdump-fortran-optimized, -fno-dump-fortran-optimized
3883
3884.. option:: -fdump-fortran-original, -fno-dump-fortran-original
3885
3886.. option:: -fdump-parse-tree, -fno-dump-parse-tree
3887
3888.. option:: -fexternal-blas, -fno-external-blas
3889
3890.. option:: -ff2c, -fno-f2c
3891
3892.. option:: -ffpe-trap=<arg>
3893
3894.. option:: -ffree-line-length-<arg>
3895
3896.. option:: -ffrontend-optimize, -fno-frontend-optimize
3897
3898.. option:: -finit-character=<arg>
3899
3900.. option:: -finit-integer=<arg>
3901
3902.. option:: -finit-local-zero, -fno-init-local-zero
3903
3904.. option:: -finit-logical=<arg>
3905
3906.. option:: -finit-real=<arg>
3907
3908.. option:: -finteger-4-integer-8, -fno-integer-4-integer-8
3909
3910.. option:: -fmax-array-constructor=<arg>
3911
3912.. option:: -fmax-errors=<arg>
3913
3914.. option:: -fmax-identifier-length, -fno-max-identifier-length
3915
3916.. option:: -fmax-stack-var-size=<arg>
3917
3918.. option:: -fmax-subrecord-length=<arg>
3919
3920.. option:: -fmodule-private, -fno-module-private
3921
3922.. option:: -fpack-derived, -fno-pack-derived
3923
3924.. option:: -fprotect-parens, -fno-protect-parens
3925
3926.. option:: -frange-check, -fno-range-check
3927
3928.. option:: -freal-4-real-10, -fno-real-4-real-10
3929
3930.. option:: -freal-4-real-16, -fno-real-4-real-16
3931
3932.. option:: -freal-4-real-8, -fno-real-4-real-8
3933
3934.. option:: -freal-8-real-10, -fno-real-8-real-10
3935
3936.. option:: -freal-8-real-16, -fno-real-8-real-16
3937
3938.. option:: -freal-8-real-4, -fno-real-8-real-4
3939
3940.. option:: -frealloc-lhs, -fno-realloc-lhs
3941
3942.. option:: -frecord-marker=<arg>
3943
3944.. option:: -frecursive, -fno-recursive
3945
3946.. option:: -frepack-arrays, -fno-repack-arrays
3947
3948.. option:: -fsecond-underscore, -fno-second-underscore
3949
3950.. option:: -fsign-zero, -fno-sign-zero
3951
3952.. option:: -fstack-arrays, -fno-stack-arrays
3953
3954.. option:: -funderscoring, -fno-underscoring
3955
3956.. option:: -fwhole-file, -fno-whole-file
3957
3958.. option:: -imultilib <arg>
3959
3960.. option:: -static-libgfortran
3961
3962Linker flags
3963============
3964Flags that are passed on to the linker
3965
3966.. option:: -L<dir>, --library-directory <arg>, --library-directory=<arg>
3967
3968Add directory to library search path
3969
3970.. option:: -Mach
3971
3972.. option:: -T<script>
3973
3974Specify <script> as linker script
3975
3976.. option:: -Tbss<addr>
3977
3978Set starting address of BSS to <addr>
3979
3980.. option:: -Tdata<addr>
3981
3982Set starting address of DATA to <addr>
3983
3984.. option:: -Ttext<addr>
3985
3986Set starting address of TEXT to <addr>
3987
3988.. option:: -Wl,<arg>,<arg2>...
3989
3990Pass the comma separated arguments in <arg> to the linker
3991
3992.. option:: -X
3993
3994.. option:: -Xlinker <arg>, --for-linker <arg>, --for-linker=<arg>
3995
3996Pass <arg> to the linker
3997
3998.. program:: clang1
3999.. option:: -Z
4000.. program:: clang
4001
4002.. option:: -coverage, --coverage
4003
4004.. option:: -e<arg>, --entry
4005
4006.. option:: -filelist <arg>
4007
4008.. option:: --hip-device-lib=<arg>
4009
4010HIP device library
4011
4012.. option:: -l<arg>
4013
4014.. option:: --ld-path=<arg>
4015
4016.. option:: -nostartfiles
4017
4018.. program:: clang1
4019.. option:: -nostdlib, --no-standard-libraries
4020.. program:: clang
4021
4022.. option:: -pie
4023
4024.. option:: -r
4025
4026.. option:: -rdynamic
4027
4028.. option:: --rocm-device-lib-path=<arg>, --hip-device-lib-path=<arg>
4029
4030ROCm device library path. Alternative to rocm-path.
4031
4032.. option:: -rpath <arg>
4033
4034.. option:: -s
4035
4036.. option:: -shared, --shared
4037
4038.. option:: -specs=<arg>, --specs=<arg>
4039
4040.. option:: -static, --static
4041
4042.. option:: -static-pie
4043
4044.. option:: -t
4045
4046.. option:: -u<arg>, --force-link <arg>, --force-link=<arg>
4047
4048.. option:: -undef
4049
4050undef all system defines
4051
4052.. option:: -undefined<arg>, --no-undefined
4053
4054.. option:: -z <arg>
4055
4056Pass -z <arg> to the linker
4057
4058