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<dir>, --prefix <arg>, --prefix=<arg> 22 23Add <dir> to search path for binaries and object files used implicitly 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.. option:: -Xcuda-fatbinary <arg> 60 61Pass <arg> to fatbinary invocation 62 63.. option:: -Xcuda-ptxas <arg> 64 65Pass <arg> to the ptxas assembler 66 67.. option:: -Xopenmp-target <arg> 68 69Pass <arg> to the target offloading toolchain. 70 71.. program:: clang1 72.. option:: -Xopenmp-target=<triple> <arg> 73.. program:: clang 74 75Pass <arg> to the target offloading toolchain identified by <triple>. 76 77.. option:: -Z<arg> 78 79.. option:: -a<arg>, --profile-blocks 80 81.. option:: -all\_load 82 83.. option:: -allowable\_client <arg> 84 85.. option:: --analyze 86 87Run the static analyzer 88 89.. option:: --analyze-auto 90 91.. option:: --analyzer-no-default-checks 92 93.. option:: --analyzer-output<arg> 94 95Static analyzer report output format (html\|plist\|plist-multi-file\|plist-html\|text). 96 97.. option:: -ansi, --ansi 98 99.. option:: -arch <arg> 100 101.. program:: clang1 102.. option:: -arch\_errors\_fatal 103.. program:: clang 104 105.. program:: clang2 106.. option:: -arch\_only <arg> 107.. program:: clang 108 109.. option:: -arcmt-migrate-emit-errors 110 111Emit ARC errors even if the migrator can fix them 112 113.. option:: -arcmt-migrate-report-output <arg> 114 115Output path for the plist report 116 117.. option:: --autocomplete=<arg> 118 119.. option:: -bind\_at\_load 120 121.. option:: -bundle 122 123.. program:: clang1 124.. option:: -bundle\_loader <arg> 125.. program:: clang 126 127.. option:: -cfguard 128 129Emit tables required for Windows Control Flow Guard. 130 131.. option:: -client\_name<arg> 132 133.. option:: -compatibility\_version<arg> 134 135.. option:: --config <arg> 136 137Specifies configuration file 138 139.. option:: --constant-cfstrings 140 141.. option:: -coverage, --coverage 142 143.. option:: --cuda-compile-host-device 144 145Compile CUDA code for both host and device (default). Has no effect on non-CUDA compilations. 146 147.. option:: --cuda-device-only 148 149Compile CUDA code for device only 150 151.. option:: --cuda-gpu-arch=<arg>, --no-cuda-gpu-arch=<arg> 152 153CUDA GPU architecture (e.g. sm\_35). May be specified more than once. 154 155.. option:: --cuda-host-only 156 157Compile CUDA code for host only. Has no effect on non-CUDA compilations. 158 159.. option:: --cuda-include-ptx=<arg>, --no-cuda-include-ptx=<arg> 160 161Include PTX for the following GPU architecture (e.g. sm\_35) or 'all'. May be specified more than once. 162 163.. option:: --cuda-noopt-device-debug, --no-cuda-noopt-device-debug 164 165Enable device-side debug info generation. Disables ptxas optimizations. 166 167.. option:: -current\_version<arg> 168 169.. option:: -dead\_strip 170 171.. option:: -dependency-dot <arg> 172 173Filename to write DOT-formatted header dependencies to 174 175.. option:: -dependency-file <arg> 176 177Filename (or -) to write dependency output to 178 179.. option:: -dumpmachine 180 181.. option:: -dumpversion 182 183.. option:: --dyld-prefix=<arg>, --dyld-prefix <arg> 184 185.. option:: -dylib\_file <arg> 186 187.. option:: -dylinker 188 189.. program:: clang1 190.. option:: -dylinker\_install\_name<arg> 191.. program:: clang 192 193.. option:: -dynamic 194 195.. option:: -dynamiclib 196 197.. option:: -emit-ast 198 199Emit Clang AST files for source inputs 200 201.. option:: -exported\_symbols\_list <arg> 202 203.. option:: -faligned-new=<arg> 204 205.. option:: -fcuda-approx-transcendentals, -fno-cuda-approx-transcendentals 206 207Use approximate transcendental functions 208 209.. option:: -fcuda-flush-denormals-to-zero, -fno-cuda-flush-denormals-to-zero 210 211Flush denormal floating point values to zero in CUDA device mode. 212 213.. option:: -fcuda-rdc, -fno-cuda-rdc 214 215Generate relocatable device code, also known as separate compilation mode. 216 217.. option:: -fcuda-short-ptr, -fno-cuda-short-ptr 218 219Use 32-bit pointers for accessing const/local/shared address spaces. 220 221.. option:: -ffixed-r19 222 223Reserve register r19 (Hexagon only) 224 225.. option:: -fheinous-gnu-extensions 226 227.. option:: -flat\_namespace 228 229.. option:: -fopenmp-targets=<arg1>,<arg2>... 230 231Specify comma-separated list of triples OpenMP offloading targets to be supported 232 233.. option:: -force\_cpusubtype\_ALL 234 235.. program:: clang1 236.. option:: -force\_flat\_namespace 237.. program:: clang 238 239.. program:: clang2 240.. option:: -force\_load <arg> 241.. program:: clang 242 243.. option:: -framework <arg> 244 245.. option:: -frtlib-add-rpath, -fno-rtlib-add-rpath 246 247Add -rpath with architecture-specific resource directory to the linker flags 248 249.. option:: --gcc-toolchain=<arg>, -gcc-toolchain <arg> 250 251Use the gcc toolchain at the given directory 252 253.. option:: -gcodeview 254 255Generate CodeView debug information 256 257.. option:: -headerpad\_max\_install\_names<arg> 258 259.. option:: -help, --help 260 261Display available options 262 263.. option:: --help-hidden 264 265Display help for hidden options 266 267.. option:: --hip-link 268 269Link clang-offload-bundler bundles for HIP 270 271.. option:: -image\_base <arg> 272 273.. option:: -index-header-map 274 275Make the next included directory (-I or -F) an indexer header map 276 277.. option:: -init <arg> 278 279.. option:: -install\_name <arg> 280 281.. option:: -keep\_private\_externs 282 283.. option:: -lazy\_framework <arg> 284 285.. program:: clang1 286.. option:: -lazy\_library <arg> 287.. program:: clang 288 289.. option:: -mbig-endian, -EB 290 291.. option:: --migrate 292 293Run the migrator 294 295.. option:: -mios-simulator-version-min=<arg>, -miphonesimulator-version-min=<arg> 296 297.. option:: -mlinker-version=<arg> 298 299.. option:: -mlittle-endian, -EL 300 301.. option:: -mllvm <arg> 302 303Additional arguments to forward to LLVM's option processing 304 305.. option:: -module-dependency-dir <arg> 306 307Directory to dump module dependencies to 308 309.. option:: -mtvos-simulator-version-min=<arg>, -mappletvsimulator-version-min=<arg> 310 311.. option:: -multi\_module 312 313.. option:: -multiply\_defined <arg> 314 315.. program:: clang1 316.. option:: -multiply\_defined\_unused <arg> 317.. program:: clang 318 319.. option:: -mwatchos-simulator-version-min=<arg>, -mwatchsimulator-version-min=<arg> 320 321.. option:: --no-cuda-version-check 322 323Don't error out if the detected version of the CUDA install is too low for the requested CUDA gpu architecture. 324 325.. option:: -no-integrated-cpp, --no-integrated-cpp 326 327.. option:: -no\_dead\_strip\_inits\_and\_terms 328 329.. option:: -nobuiltininc 330 331Disable builtin #include directories 332 333.. option:: -nocudainc 334 335.. option:: -nocudalib 336 337.. option:: -nodefaultlibs 338 339.. option:: -nofixprebinding 340 341.. option:: -nolibc 342 343.. option:: -nomultidefs 344 345.. option:: -nopie, -no-pie 346 347.. option:: -noprebind 348 349.. option:: -noprofilelib 350 351.. option:: -noseglinkedit 352 353.. option:: -nostartfiles 354 355.. option:: -nostdinc, --no-standard-includes 356 357.. program:: clang1 358.. option:: -nostdinc++ 359.. program:: clang 360 361Disable standard #include directories for the C++ standard library 362 363.. option:: -nostdlib, --no-standard-libraries 364 365.. program:: clang1 366.. option:: -nostdlib++ 367.. program:: clang 368 369.. option:: -nostdlibinc 370 371.. option:: -o<file>, --output <arg>, --output=<arg> 372 373Write output to <file> 374 375.. option:: -objcmt-atomic-property 376 377Make migration to 'atomic' properties 378 379.. option:: -objcmt-migrate-all 380 381Enable migration to modern ObjC 382 383.. option:: -objcmt-migrate-annotation 384 385Enable migration to property and method annotations 386 387.. option:: -objcmt-migrate-designated-init 388 389Enable migration to infer NS\_DESIGNATED\_INITIALIZER for initializer methods 390 391.. option:: -objcmt-migrate-instancetype 392 393Enable migration to infer instancetype for method result type 394 395.. option:: -objcmt-migrate-literals 396 397Enable migration to modern ObjC literals 398 399.. option:: -objcmt-migrate-ns-macros 400 401Enable migration to NS\_ENUM/NS\_OPTIONS macros 402 403.. option:: -objcmt-migrate-property 404 405Enable migration to modern ObjC property 406 407.. option:: -objcmt-migrate-property-dot-syntax 408 409Enable migration of setter/getter messages to property-dot syntax 410 411.. option:: -objcmt-migrate-protocol-conformance 412 413Enable migration to add protocol conformance on classes 414 415.. option:: -objcmt-migrate-readonly-property 416 417Enable migration to modern ObjC readonly property 418 419.. option:: -objcmt-migrate-readwrite-property 420 421Enable migration to modern ObjC readwrite property 422 423.. option:: -objcmt-migrate-subscripting 424 425Enable migration to modern ObjC subscripting 426 427.. option:: -objcmt-ns-nonatomic-iosonly 428 429Enable migration to use NS\_NONATOMIC\_IOSONLY macro for setting property's 'atomic' attribute 430 431.. option:: -objcmt-returns-innerpointer-property 432 433Enable migration to annotate property with NS\_RETURNS\_INNER\_POINTER 434 435.. option:: -objcmt-whitelist-dir-path=<arg>, -objcmt-white-list-dir-path=<arg> 436 437Only modify files with a filename contained in the provided directory path 438 439.. option:: -object 440 441.. option:: -p, --profile 442 443.. option:: -pagezero\_size<arg> 444 445.. option:: -pg 446 447Enable mcount instrumentation 448 449.. option:: -pie 450 451.. option:: -pipe, --pipe 452 453Use pipes between commands, when possible 454 455.. option:: -prebind 456 457.. program:: clang1 458.. option:: -prebind\_all\_twolevel\_modules 459.. program:: clang 460 461.. option:: -preload 462 463.. option:: --print-diagnostic-categories 464 465.. option:: -print-effective-triple, --print-effective-triple 466 467Print the effective target triple 468 469.. option:: -print-file-name=<file>, --print-file-name=<file>, --print-file-name <arg> 470 471Print the full library path of <file> 472 473.. option:: -print-ivar-layout 474 475Enable Objective-C Ivar layout bitmap print trace 476 477.. option:: -print-libgcc-file-name, --print-libgcc-file-name 478 479Print the library path for the currently used compiler runtime library ("libgcc.a" or "libclang\_rt.builtins.\*.a") 480 481.. option:: -print-multi-directory, --print-multi-directory 482 483.. option:: -print-multi-lib, --print-multi-lib 484 485.. option:: -print-prog-name=<name>, --print-prog-name=<name>, --print-prog-name <arg> 486 487Print the full program path of <name> 488 489.. option:: -print-resource-dir, --print-resource-dir 490 491Print the resource directory pathname 492 493.. option:: -print-search-dirs, --print-search-dirs 494 495Print the paths used for finding libraries and programs 496 497.. option:: -print-target-triple, --print-target-triple 498 499Print the normalized target triple 500 501.. option:: -private\_bundle 502 503.. option:: -pthread, -no-pthread 504 505Support POSIX threads in generated code 506 507.. option:: -pthreads 508 509.. option:: -rdynamic 510 511.. option:: -read\_only\_relocs <arg> 512 513.. option:: -relocatable-pch, --relocatable-pch 514 515Whether to build a relocatable precompiled header 516 517.. option:: -remap 518 519.. option:: -rewrite-legacy-objc 520 521Rewrite Legacy Objective-C source to C++ 522 523.. option:: -rtlib=<arg>, --rtlib=<arg>, --rtlib <arg> 524 525Compiler runtime library to use 526 527.. option:: -save-stats=<arg>, --save-stats=<arg>, -save-stats (equivalent to -save-stats=cwd), --save-stats (equivalent to -save-stats=cwd) 528 529Save llvm statistics. 530 531.. option:: -save-temps=<arg>, --save-temps=<arg>, -save-temps (equivalent to -save-temps=cwd), --save-temps (equivalent to -save-temps=cwd) 532 533Save intermediate compilation results. 534 535.. option:: -sectalign <arg1> <arg2> <arg3> 536 537.. option:: -sectcreate <arg1> <arg2> <arg3> 538 539.. option:: -sectobjectsymbols <arg1> <arg2> 540 541.. option:: -sectorder <arg1> <arg2> <arg3> 542 543.. option:: -seg1addr<arg> 544 545.. option:: -seg\_addr\_table <arg> 546 547.. program:: clang1 548.. option:: -seg\_addr\_table\_filename <arg> 549.. program:: clang 550 551.. option:: -segaddr <arg1> <arg2> 552 553.. option:: -segcreate <arg1> <arg2> <arg3> 554 555.. option:: -seglinkedit 556 557.. option:: -segprot <arg1> <arg2> <arg3> 558 559.. option:: -segs\_read\_<arg> 560 561.. program:: clang1 562.. option:: -segs\_read\_only\_addr <arg> 563.. program:: clang 564 565.. program:: clang2 566.. option:: -segs\_read\_write\_addr <arg> 567.. program:: clang 568 569.. option:: -serialize-diagnostics <arg>, --serialize-diagnostics <arg> 570 571Serialize compiler diagnostics to a file 572 573.. option:: -shared, --shared 574 575.. option:: -shared-libgcc 576 577.. option:: -shared-libsan, -shared-libasan 578 579Dynamically link the sanitizer runtime 580 581.. option:: -single\_module 582 583.. option:: -specs=<arg>, --specs=<arg> 584 585.. option:: -static, --static 586 587.. option:: -static-libgcc 588 589.. option:: -static-libsan 590 591Statically link the sanitizer runtime 592 593.. option:: -static-libstdc++ 594 595.. option:: -std-default=<arg> 596 597.. option:: -stdlib=<arg>, --stdlib=<arg>, --stdlib <arg> 598 599C++ standard library to use 600 601.. option:: -sub\_library<arg> 602 603.. program:: clang1 604.. option:: -sub\_umbrella<arg> 605.. program:: clang 606 607.. option:: --sysroot=<arg>, --sysroot <arg> 608 609.. option:: --target-help 610 611.. option:: --target=<arg>, -target <arg> 612 613Generate code for the given target 614 615.. option:: --print-supported-cpus 616 617Print supported cpu models for the given target 618 619.. option:: -time 620 621Time individual commands 622 623.. option:: -traditional, --traditional 624 625.. option:: -traditional-cpp, --traditional-cpp 626 627Enable some traditional CPP emulation 628 629.. option:: -twolevel\_namespace 630 631.. program:: clang1 632.. option:: -twolevel\_namespace\_hints 633.. program:: clang 634 635.. option:: -umbrella <arg> 636 637.. option:: -unexported\_symbols\_list <arg> 638 639.. option:: -v, --verbose 640 641Show commands to run and use verbose output 642 643.. option:: --verify-debug-info 644 645Verify the binary representation of debug output 646 647.. option:: --version 648 649Print version information 650 651.. option:: -w, --no-warnings 652 653Suppress all warnings 654 655.. option:: -weak-l<arg> 656 657.. option:: -weak\_framework <arg> 658 659.. program:: clang1 660.. option:: -weak\_library <arg> 661.. program:: clang 662 663.. program:: clang2 664.. option:: -weak\_reference\_mismatches <arg> 665.. program:: clang 666 667.. option:: -whatsloaded 668 669.. option:: -whyload 670 671.. option:: -working-directory<arg>, -working-directory=<arg> 672 673Resolve file paths relative to the specified directory 674 675.. option:: -x<language>, --language <arg>, --language=<arg> 676 677Treat subsequent input files as having type <language> 678 679.. option:: -y<arg> 680 681Actions 682======= 683The action to perform on the input. 684 685.. option:: -E, --preprocess 686 687Only run the preprocessor 688 689.. option:: -S, --assemble 690 691Only run preprocess and compilation steps 692 693.. option:: -c, --compile 694 695Only run preprocess, compile, and assemble steps 696 697.. option:: -emit-llvm 698 699Use the LLVM representation for assembler and object files 700 701.. option:: -fsyntax-only 702 703.. option:: -module-file-info 704 705Provide information about a particular module file 706 707.. option:: --precompile 708 709Only precompile the input 710 711.. option:: -rewrite-objc 712 713Rewrite Objective-C source to C++ 714 715.. option:: -verify-pch 716 717Load and verify that a pre-compiled header file is not stale 718 719Compilation flags 720================= 721 722Flags controlling the behavior of Clang during compilation. These flags have 723no effect during actions that do not perform compilation. 724 725.. option:: -Xassembler <arg> 726 727Pass <arg> to the assembler 728 729.. option:: -Xclang <arg> 730 731Pass <arg> to the clang compiler 732 733.. option:: -fclang-abi-compat=<version> 734 735Attempt to match the ABI of Clang <version> 736 737.. option:: -fcomment-block-commands=<arg>,<arg2>... 738 739Treat each comma separated argument in <arg> as a documentation comment block command 740 741.. option:: -fcomplete-member-pointers, -fno-complete-member-pointers 742 743Require member pointer base types to be complete if they would be significant under the Microsoft ABI 744 745.. option:: -fcrash-diagnostics-dir=<arg> 746 747.. option:: -fdeclspec, -fno-declspec 748 749Allow \_\_declspec as a keyword 750 751.. option:: -fdepfile-entry=<arg> 752 753.. option:: -fdiagnostics-fixit-info, -fno-diagnostics-fixit-info 754 755.. option:: -fdiagnostics-format=<arg> 756 757.. option:: -fdiagnostics-parseable-fixits 758 759Print fix-its in machine parseable form 760 761.. option:: -fdiagnostics-print-source-range-info 762 763Print source range spans in numeric form 764 765.. option:: -fdiagnostics-show-category=<arg> 766 767.. option:: -fdiscard-value-names, -fno-discard-value-names 768 769Discard value names in LLVM IR 770 771.. option:: -fexperimental-isel, -fno-experimental-isel 772 773Enables the experimental global instruction selector 774 775.. option:: -fexperimental-new-pass-manager, -fno-experimental-new-pass-manager 776 777Enables an experimental new pass manager in LLVM. 778 779.. option:: -ffine-grained-bitfield-accesses, -fno-fine-grained-bitfield-accesses 780 781Use separate accesses for consecutive bitfield runs with legal widths and alignments. 782 783.. option:: -finline-functions, -fno-inline-functions 784 785Inline suitable functions 786 787.. option:: -finline-hint-functions 788 789Inline functions which are (explicitly or implicitly) marked inline 790 791.. option:: -fno-crash-diagnostics 792 793Disable auto-generation of preprocessed source files and a script for reproduction during a clang crash 794 795.. option:: -fno-sanitize-blacklist 796 797Don't use blacklist file for sanitizers 798 799.. option:: -fparse-all-comments 800 801.. option:: -frecord-command-line, -frecord-gcc-switches, -fno-record-command-line, -fno-record-gcc-switches 802 803Generate a section named ".GCC.command.line" containing the clang driver 804command-line. After linking, the section may contain multiple command lines, 805which will be individually terminated by null bytes. Separate arguments within 806a command line are combined with spaces; spaces and backslashes within an 807argument are escaped with backslashes. This format differs from the format of 808the equivalent section produced by GCC with the -frecord-gcc-switches flag. 809This option is currently only supported on ELF targets. 810 811.. option:: -fsanitize-address-field-padding=<arg> 812 813Level of field padding for AddressSanitizer 814 815.. option:: -fsanitize-address-globals-dead-stripping 816 817Enable linker dead stripping of globals in AddressSanitizer 818 819.. option:: -fsanitize-address-use-odr-indicator, -fno-sanitize-address-use-odr-indicator 820 821Enable ODR indicator globals to avoid false ODR violation reports in partially sanitized programs at the cost of an increase in binary size 822 823.. option:: -fsanitize-address-poison-custom-array-cookie, -fno-sanitize-address-poison-custom-array-cookie 824 825Enable "poisoning" array cookies when allocating arrays with a custom operator new\[\] in Address Sanitizer, preventing accesses to the cookies from user code. An array cookie is a small implementation-defined header added to certain array allocations to record metadata such as the length of the array. Accesses to array cookies from user code are technically allowed by the standard but are more likely to be the result of an out-of-bounds array access. 826 827An operator new\[\] is "custom" if it is not one of the allocation functions provided by the C++ standard library. Array cookies from non-custom allocation functions are always poisoned. 828 829.. option:: -fsanitize-address-use-after-scope, -fno-sanitize-address-use-after-scope 830 831Enable use-after-scope detection in AddressSanitizer 832 833.. option:: -fsanitize-blacklist=<arg> 834 835Path to blacklist file for sanitizers 836 837.. option:: -fsanitize-cfi-cross-dso, -fno-sanitize-cfi-cross-dso 838 839Enable control flow integrity (CFI) checks for cross-DSO calls. 840 841.. option:: -fsanitize-cfi-icall-generalize-pointers 842 843Generalize pointers in CFI indirect call type signature checks 844 845.. option:: -fsanitize-coverage=<arg1>,<arg2>..., -fno-sanitize-coverage=<arg1>,<arg2>... 846 847Specify the type of coverage instrumentation for Sanitizers 848 849.. option:: -fsanitize-link-c++-runtime 850 851.. option:: -fsanitize-memory-track-origins, -fno-sanitize-memory-track-origins 852 853Enable origins tracking in MemorySanitizer 854 855.. program:: clang1 856.. option:: -fsanitize-memory-track-origins=<arg> 857.. program:: clang 858 859Enable origins tracking in MemorySanitizer 860 861.. option:: -fsanitize-memory-use-after-dtor, -fno-sanitize-memory-use-after-dtor 862 863Enable use-after-destroy detection in MemorySanitizer 864 865.. option:: -fsanitize-minimal-runtime, -fno-sanitize-minimal-runtime 866 867.. option:: -fsanitize-recover, -fno-sanitize-recover 868 869.. program:: clang1 870.. option:: -fsanitize-recover=<arg1>,<arg2>..., -fno-sanitize-recover=<arg1>,<arg2>... 871.. program:: clang 872 873Enable recovery for specified sanitizers 874 875.. option:: -fsanitize-stats, -fno-sanitize-stats 876 877Enable sanitizer statistics gathering. 878 879.. option:: -fsanitize-thread-atomics, -fno-sanitize-thread-atomics 880 881Enable atomic operations instrumentation in ThreadSanitizer (default) 882 883.. option:: -fsanitize-thread-func-entry-exit, -fno-sanitize-thread-func-entry-exit 884 885Enable function entry/exit instrumentation in ThreadSanitizer (default) 886 887.. option:: -fsanitize-thread-memory-access, -fno-sanitize-thread-memory-access 888 889Enable memory access instrumentation in ThreadSanitizer (default) 890 891.. option:: -fsanitize-trap=<arg1>,<arg2>..., -fno-sanitize-trap=<arg1>,<arg2>... 892 893Enable trapping for specified sanitizers 894 895.. option:: -fsanitize-undefined-strip-path-components=<number> 896 897Strip (or keep only, if negative) a given number of path components when emitting check metadata. 898 899.. option:: -fsanitize-undefined-trap-on-error, -fno-sanitize-undefined-trap-on-error 900 901.. option:: -fsanitize=<check>,<arg2>..., -fno-sanitize=<arg1>,<arg2>... 902 903Turn on runtime checks for various forms of undefined or suspicious behavior. See user manual for available checks 904 905.. option:: -moutline, -mno-outline 906 907Enable function outlining (AArch64 only) 908 909.. option:: --param <arg>, --param=<arg> 910 911.. option:: -std=<arg>, --std=<arg>, --std <arg> 912 913Language standard to compile for 914 915Preprocessor flags 916~~~~~~~~~~~~~~~~~~ 917 918Flags controlling the behavior of the Clang preprocessor. 919 920.. option:: -C, --comments 921 922Include comments in preprocessed output 923 924.. option:: -CC, --comments-in-macros 925 926Include comments from within macros in preprocessed output 927 928.. option:: -D<macro>=<value>, --define-macro <arg>, --define-macro=<arg> 929 930Define <macro> to <value> (or 1 if <value> omitted) 931 932.. option:: -H, --trace-includes 933 934Show header includes and nesting depth 935 936.. option:: -P, --no-line-commands 937 938Disable linemarker output in -E mode 939 940.. option:: -U<macro>, --undefine-macro <arg>, --undefine-macro=<arg> 941 942Undefine macro <macro> 943 944.. option:: -Wp,<arg>,<arg2>... 945 946Pass the comma separated arguments in <arg> to the preprocessor 947 948.. option:: -Xpreprocessor <arg> 949 950Pass <arg> to the preprocessor 951 952Include path management 953----------------------- 954 955Flags controlling how ``#include``\s are resolved to files. 956 957.. option:: -I<dir>, --include-directory <arg>, --include-directory=<arg> 958 959Add directory to include search path 960 961.. option:: -I-, --include-barrier 962 963Restrict all prior -I flags to double-quoted inclusion and remove current directory from include path 964 965.. option:: --cuda-path-ignore-env 966 967Ignore environment variables to detect CUDA installation 968 969.. option:: --cuda-path=<arg> 970 971CUDA installation path 972 973.. option:: -cxx-isystem<directory> 974 975Add directory to the C++ SYSTEM include search path 976 977.. option:: -fbuild-session-file=<file> 978 979Use the last modification time of <file> as the build session timestamp 980 981.. option:: -fbuild-session-timestamp=<time since Epoch in seconds> 982 983Time when the current build session started 984 985.. option:: -fmodule-file=\[<name>=\]<file> 986 987Specify the mapping of module name to precompiled module file, or load a module file if name is omitted. 988 989.. option:: -fmodules-cache-path=<directory> 990 991Specify the module cache path 992 993.. option:: -fmodules-disable-diagnostic-validation 994 995Disable validation of the diagnostic options when loading the module 996 997.. option:: -fmodules-prune-after=<seconds> 998 999Specify the interval (in seconds) after which a module file will be considered unused 1000 1001.. option:: -fmodules-prune-interval=<seconds> 1002 1003Specify the interval (in seconds) between attempts to prune the module cache 1004 1005.. option:: -fmodules-user-build-path <directory> 1006 1007Specify the module user build path 1008 1009.. option:: -fmodules-validate-once-per-build-session 1010 1011Don't verify input files for the modules if the module has been successfully validated or loaded during this build session 1012 1013.. option:: -fmodules-validate-system-headers, -fno-modules-validate-system-headers 1014 1015Validate the system headers that a module depends on when loading the module 1016 1017.. option:: -fprebuilt-module-path=<directory> 1018 1019Specify the prebuilt module path 1020 1021.. option:: -idirafter<arg>, --include-directory-after <arg>, --include-directory-after=<arg> 1022 1023Add directory to AFTER include search path 1024 1025.. option:: -iframework<arg> 1026 1027Add directory to SYSTEM framework search path 1028 1029.. option:: -iframeworkwithsysroot<directory> 1030 1031Add directory to SYSTEM framework search path, absolute paths are relative to -isysroot 1032 1033.. option:: -imacros<file>, --imacros<file>, --imacros=<arg> 1034 1035Include macros from file before parsing 1036 1037.. option:: -include<file>, --include<file>, --include=<arg> 1038 1039Include file before parsing 1040 1041.. option:: -include-pch <file> 1042 1043Include precompiled header file 1044 1045.. option:: -iprefix<dir>, --include-prefix <arg>, --include-prefix=<arg> 1046 1047Set the -iwithprefix/-iwithprefixbefore prefix 1048 1049.. option:: -iquote<directory> 1050 1051Add directory to QUOTE include search path 1052 1053.. option:: -isysroot<dir> 1054 1055Set the system root directory (usually /) 1056 1057.. option:: -isystem<directory> 1058 1059Add directory to SYSTEM include search path 1060 1061.. option:: -isystem-after<directory> 1062 1063Add directory to end of the SYSTEM include search path 1064 1065.. option:: -ivfsoverlay<arg> 1066 1067Overlay the virtual filesystem described by file over the real file system 1068 1069.. option:: -iwithprefix<dir>, --include-with-prefix <arg>, --include-with-prefix-after <arg>, --include-with-prefix-after=<arg>, --include-with-prefix=<arg> 1070 1071Set directory to SYSTEM include search path with prefix 1072 1073.. option:: -iwithprefixbefore<dir>, --include-with-prefix-before <arg>, --include-with-prefix-before=<arg> 1074 1075Set directory to include search path with prefix 1076 1077.. option:: -iwithsysroot<directory> 1078 1079Add directory to SYSTEM include search path, absolute paths are relative to -isysroot 1080 1081.. option:: --ptxas-path=<arg> 1082 1083Path to ptxas (used for compiling CUDA code) 1084 1085.. option:: --system-header-prefix=<prefix>, --no-system-header-prefix=<prefix>, --system-header-prefix <arg> 1086 1087Treat all #include paths starting with <prefix> as including a system header. 1088 1089Dependency file generation 1090-------------------------- 1091 1092Flags controlling generation of a dependency file for ``make``-like build 1093systems. 1094 1095.. option:: -M, --dependencies 1096 1097Like -MD, but also implies -E and writes to stdout by default 1098 1099.. option:: -MD, --write-dependencies 1100 1101Write a depfile containing user and system headers 1102 1103.. option:: -MF<file> 1104 1105Write depfile output from -MMD, -MD, -MM, or -M to <file> 1106 1107.. option:: -MG, --print-missing-file-dependencies 1108 1109Add missing headers to depfile 1110 1111.. option:: -MJ<arg> 1112 1113Write a compilation database entry per input 1114 1115.. option:: -MM, --user-dependencies 1116 1117Like -MMD, but also implies -E and writes to stdout by default 1118 1119.. option:: -MMD, --write-user-dependencies 1120 1121Write a depfile containing user headers 1122 1123.. option:: -MP 1124 1125Create phony target for each dependency (other than main file) 1126 1127.. option:: -MQ<arg> 1128 1129Specify name of main file output to quote in depfile 1130 1131.. option:: -MT<arg> 1132 1133Specify name of main file output in depfile 1134 1135.. option:: -MV 1136 1137Use NMake/Jom format for the depfile 1138 1139Dumping preprocessor state 1140-------------------------- 1141 1142Flags allowing the state of the preprocessor to be dumped in various ways. 1143 1144.. option:: -d 1145 1146.. program:: clang1 1147.. option:: -d<arg> 1148.. program:: clang 1149 1150.. option:: -dA 1151 1152.. option:: -dD 1153 1154Print macro definitions in -E mode in addition to normal output 1155 1156.. option:: -dI 1157 1158Print include directives in -E mode in addition to normal output 1159 1160.. option:: -dM 1161 1162Print macro definitions in -E mode instead of normal output 1163 1164Diagnostic flags 1165~~~~~~~~~~~~~~~~ 1166 1167Flags controlling which warnings, errors, and remarks Clang will generate. 1168See the :doc:`full list of warning and remark flags <DiagnosticsReference>`. 1169 1170.. option:: -R<remark> 1171 1172Enable the specified remark 1173 1174.. option:: -Rpass-analysis=<arg> 1175 1176Report transformation analysis from optimization passes whose name matches the given POSIX regular expression 1177 1178.. option:: -Rpass-missed=<arg> 1179 1180Report missed transformations by optimization passes whose name matches the given POSIX regular expression 1181 1182.. option:: -Rpass=<arg> 1183 1184Report transformations performed by optimization passes whose name matches the given POSIX regular expression 1185 1186.. option:: -W<warning>, --extra-warnings, --warn-<arg>, --warn-=<arg> 1187 1188Enable the specified warning 1189 1190.. option:: -Wdeprecated, -Wno-deprecated 1191 1192Enable warnings for deprecated constructs and define \_\_DEPRECATED 1193 1194.. option:: -Wnonportable-cfstrings<arg>, -Wno-nonportable-cfstrings<arg> 1195 1196Target-independent compilation options 1197~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 1198.. option:: -Wframe-larger-than=<arg> 1199 1200.. option:: -fPIC, -fno-PIC 1201 1202.. option:: -fPIE, -fno-PIE 1203 1204.. option:: -faccess-control, -fno-access-control 1205 1206.. option:: -faddrsig, -fno-addrsig 1207 1208Emit an address-significance table 1209 1210.. option:: -falign-functions, -fno-align-functions 1211 1212.. program:: clang1 1213.. option:: -falign-functions=<arg> 1214.. program:: clang 1215 1216.. program:: clang1 1217.. option:: -faligned-allocation, -faligned-new, -fno-aligned-allocation 1218.. program:: clang 1219 1220Enable C++17 aligned allocation functions 1221 1222.. option:: -fallow-editor-placeholders, -fno-allow-editor-placeholders 1223 1224Treat editor placeholders as valid source code 1225 1226.. option:: -fallow-unsupported 1227 1228.. option:: -faltivec, -fno-altivec 1229 1230.. option:: -fansi-escape-codes 1231 1232Use ANSI escape codes for diagnostics 1233 1234.. option:: -fapple-kext, -findirect-virtual-calls, -fterminated-vtables 1235 1236Use Apple's kernel extensions ABI 1237 1238.. option:: -fapple-pragma-pack, -fno-apple-pragma-pack 1239 1240Enable Apple gcc-compatible #pragma pack handling 1241 1242.. option:: -fapplication-extension, -fno-application-extension 1243 1244Restrict code to those available for App Extensions 1245 1246.. option:: -fasm, -fno-asm 1247 1248.. option:: -fasm-blocks, -fno-asm-blocks 1249 1250.. option:: -fassociative-math, -fno-associative-math 1251 1252.. option:: -fassume-sane-operator-new, -fno-assume-sane-operator-new 1253 1254.. option:: -fast 1255 1256.. option:: -fastcp 1257 1258.. option:: -fastf 1259 1260.. option:: -fasynchronous-unwind-tables, -fno-asynchronous-unwind-tables 1261 1262.. option:: -fautolink, -fno-autolink 1263 1264.. option:: -fblocks, -fno-blocks 1265 1266Enable the 'blocks' language feature 1267 1268.. option:: -fbootclasspath=<arg>, --bootclasspath <arg>, --bootclasspath=<arg> 1269 1270.. option:: -fborland-extensions, -fno-borland-extensions 1271 1272Accept non-standard constructs supported by the Borland compiler 1273 1274.. option:: -fbracket-depth=<arg> 1275 1276.. option:: -fbuiltin, -fno-builtin 1277 1278.. option:: -fbuiltin-module-map 1279 1280Load the clang builtins module map file. 1281 1282.. option:: -fc++-static-destructors, -fno-c++-static-destructors 1283 1284Enable C++ static destructor registration (the default) 1285 1286.. option:: -fcaret-diagnostics, -fno-caret-diagnostics 1287 1288.. option:: -fcf-protection=<arg>, -fcf-protection (equivalent to -fcf-protection=full) 1289 1290Instrument control-flow architecture protection. Options: return, branch, full, none. 1291 1292.. option:: -fchar8\_t, -fno-char8\_t 1293 1294Enable C++ builtin type char8\_t 1295 1296.. option:: -fclasspath=<arg>, --CLASSPATH <arg>, --CLASSPATH=<arg>, --classpath <arg>, --classpath=<arg> 1297 1298.. option:: -fcolor-diagnostics, -fno-color-diagnostics 1299 1300Use colors in diagnostics 1301 1302.. option:: -fcommon, -fno-common 1303 1304.. option:: -fcompile-resource=<arg>, --resource <arg>, --resource=<arg> 1305 1306.. option:: -fconstant-cfstrings, -fno-constant-cfstrings 1307 1308.. option:: -fconstant-string-class=<arg> 1309 1310.. option:: -fconstexpr-backtrace-limit=<arg> 1311 1312.. option:: -fconstexpr-depth=<arg> 1313 1314.. option:: -fconstexpr-steps=<arg> 1315 1316.. option:: -fcoroutines-ts, -fno-coroutines-ts 1317 1318Enable support for the C++ Coroutines TS 1319 1320.. option:: -fcoverage-mapping, -fno-coverage-mapping 1321 1322Generate coverage mapping to enable code coverage analysis 1323 1324.. option:: -fcreate-profile 1325 1326.. option:: -fcxx-exceptions, -fno-cxx-exceptions 1327 1328Enable C++ exceptions 1329 1330.. option:: -fcxx-modules, -fno-cxx-modules 1331 1332.. option:: -fdata-sections, -fno-data-sections 1333 1334Place each data in its own section (ELF Only) 1335 1336.. option:: -fdebug-info-for-profiling, -fno-debug-info-for-profiling 1337 1338Emit extra debug info to make sample profile more accurate. 1339 1340.. option:: -fdebug-macro, -fno-debug-macro 1341 1342Emit macro debug information 1343 1344.. option:: -fdebug-pass-arguments 1345 1346.. option:: -fdebug-pass-structure 1347 1348.. option:: -fdebug-prefix-map=<arg> 1349 1350remap file source paths in debug info 1351 1352.. option:: -fdebug-types-section, -fno-debug-types-section 1353 1354Place debug types in their own section (ELF Only) 1355 1356.. option:: -fdelayed-template-parsing, -fno-delayed-template-parsing 1357 1358Parse templated function definitions at the end of the translation unit 1359 1360.. option:: -fdelete-null-pointer-checks, -fno-delete-null-pointer-checks 1361 1362Treat usage of null pointers as undefined behavior. 1363 1364.. option:: -fdenormal-fp-math=<arg> 1365 1366.. option:: -fdiagnostics-absolute-paths 1367 1368Print absolute paths in diagnostics 1369 1370.. option:: -fdiagnostics-color, -fno-diagnostics-color 1371 1372.. program:: clang1 1373.. option:: -fdiagnostics-color=<arg> 1374.. program:: clang 1375 1376.. option:: -fdiagnostics-hotness-threshold=<number> 1377 1378Prevent optimization remarks from being output if they do not have at least this profile count 1379 1380.. option:: -fdiagnostics-show-hotness, -fno-diagnostics-show-hotness 1381 1382Enable profile hotness information in diagnostic line 1383 1384.. option:: -fdiagnostics-show-note-include-stack, -fno-diagnostics-show-note-include-stack 1385 1386Display include stacks for diagnostic notes 1387 1388.. option:: -fdiagnostics-show-option, -fno-diagnostics-show-option 1389 1390Print option name with mappable diagnostics 1391 1392.. option:: -fdiagnostics-show-template-tree 1393 1394Print a template comparison tree for differing templates 1395 1396.. option:: -fdigraphs, -fno-digraphs 1397 1398Enable alternative token representations '<:', ':>', '<%', '%>', '%:', '%:%:' (default) 1399 1400.. option:: -fdollars-in-identifiers, -fno-dollars-in-identifiers 1401 1402Allow '$' in identifiers 1403 1404.. option:: -fdouble-square-bracket-attributes, -fno-double-square-bracket-attributes 1405 1406Enable '\[\[\]\]' attributes in all C and C++ language modes 1407 1408.. option:: -fdwarf-directory-asm, -fno-dwarf-directory-asm 1409 1410.. option:: -fdwarf-exceptions 1411 1412Use DWARF style exceptions 1413 1414.. option:: -felide-constructors, -fno-elide-constructors 1415 1416.. option:: -feliminate-unused-debug-symbols, -fno-eliminate-unused-debug-symbols 1417 1418.. option:: -fembed-bitcode=<option>, -fembed-bitcode (equivalent to -fembed-bitcode=all), -fembed-bitcode-marker (equivalent to -fembed-bitcode=marker) 1419 1420Embed LLVM bitcode (option: off, all, bitcode, marker) 1421 1422.. option:: -femit-all-decls 1423 1424Emit all declarations, even if unused 1425 1426.. option:: -femulated-tls, -fno-emulated-tls 1427 1428Use emutls functions to access thread\_local variables 1429 1430.. option:: -fencoding=<arg>, --encoding <arg>, --encoding=<arg> 1431 1432.. option:: -ferror-limit=<arg> 1433 1434.. option:: -fescaping-block-tail-calls, -fno-escaping-block-tail-calls 1435 1436.. option:: -fexceptions, -fno-exceptions 1437 1438Enable support for exception handling 1439 1440.. option:: -fexec-charset=<arg> 1441 1442.. option:: -fextdirs=<arg>, --extdirs <arg>, --extdirs=<arg> 1443 1444.. option:: -ffast-math, -fno-fast-math 1445 1446Allow aggressive, lossy floating-point optimizations 1447 1448.. option:: -ffinite-math-only, -fno-finite-math-only 1449 1450.. option:: -ffixed-point, -fno-fixed-point 1451 1452Enable fixed point types 1453 1454.. option:: -ffor-scope, -fno-for-scope 1455 1456.. option:: -fforce-emit-vtables, -fno-force-emit-vtables 1457 1458Emits more virtual tables to improve devirtualization 1459 1460.. option:: -fforce-enable-int128, -fno-force-enable-int128 1461 1462Enable support for int128\_t type 1463 1464.. option:: -ffp-contract=<arg> 1465 1466Form fused FP ops (e.g. FMAs): fast (everywhere) \| on (according to FP\_CONTRACT pragma, default) \| off (never fuse) 1467 1468.. option:: -ffreestanding 1469 1470Assert that the compilation takes place in a freestanding environment 1471 1472.. option:: -ffunction-sections, -fno-function-sections 1473 1474Place each function in its own section (ELF Only) 1475 1476.. option:: -fgnu-inline-asm, -fno-gnu-inline-asm 1477 1478.. option:: -fgnu-keywords, -fno-gnu-keywords 1479 1480Allow GNU-extension keywords regardless of language standard 1481 1482.. option:: -fgnu-runtime 1483 1484Generate output compatible with the standard GNU Objective-C runtime 1485 1486.. option:: -fgnu89-inline, -fno-gnu89-inline 1487 1488Use the gnu89 inline semantics 1489 1490.. option:: -fhonor-infinities, -fhonor-infinites, -fno-honor-infinities 1491 1492.. option:: -fhonor-nans, -fno-honor-nans 1493 1494.. option:: -fhosted 1495 1496.. option:: -fimplicit-module-maps, -fmodule-maps, -fno-implicit-module-maps 1497 1498Implicitly search the file system for module map files. 1499 1500.. option:: -fimplicit-modules, -fno-implicit-modules 1501 1502.. option:: -finput-charset=<arg> 1503 1504.. option:: -finstrument-function-entry-bare 1505 1506Instrument function entry only, after inlining, without arguments to the instrumentation call 1507 1508.. option:: -finstrument-functions 1509 1510Generate calls to instrument function entry and exit 1511 1512.. option:: -finstrument-functions-after-inlining 1513 1514Like -finstrument-functions, but insert the calls after inlining 1515 1516.. option:: -fintegrated-as, -fno-integrated-as, -integrated-as 1517 1518Enable the integrated assembler 1519 1520.. option:: -fjump-tables, -fno-jump-tables 1521 1522.. option:: -fkeep-static-consts 1523 1524Keep static const variables even if unused 1525 1526.. option:: -flax-vector-conversions, -fno-lax-vector-conversions 1527 1528.. option:: -flimited-precision=<arg> 1529 1530.. option:: -flto, -fno-lto 1531 1532Enable LTO in 'full' mode 1533 1534.. option:: -flto-jobs=<arg> 1535 1536Controls the backend parallelism of -flto=thin (default of 0 means the number of threads will be derived from the number of CPUs detected) 1537 1538.. program:: clang1 1539.. option:: -flto=<arg> 1540.. program:: clang 1541 1542Set LTO mode to either 'full' or 'thin' 1543 1544.. option:: -fmacro-backtrace-limit=<arg> 1545 1546.. option:: -fmath-errno, -fno-math-errno 1547 1548Require math functions to indicate errors by setting errno 1549 1550.. option:: -fmax-type-align=<arg> 1551 1552Specify the maximum alignment to enforce on pointers lacking an explicit alignment 1553 1554.. option:: -fmerge-all-constants, -fno-merge-all-constants 1555 1556Allow merging of constants 1557 1558.. option:: -fmessage-length=<arg> 1559 1560.. option:: -fmodule-file-deps, -fno-module-file-deps 1561 1562.. option:: -fmodule-map-file=<file> 1563 1564Load this module map file 1565 1566.. option:: -fmodule-name=<name>, -fmodule-implementation-of <arg>, -fmodule-name <arg> 1567 1568Specify the name of the module to build 1569 1570.. option:: -fmodules, -fno-modules 1571 1572Enable the 'modules' language feature 1573 1574.. option:: -fmodules-decluse, -fno-modules-decluse 1575 1576Require declaration of modules used within a module 1577 1578.. option:: -fmodules-ignore-macro=<arg> 1579 1580Ignore the definition of the given macro when building and loading modules 1581 1582.. option:: -fmodules-search-all, -fno-modules-search-all 1583 1584Search even non-imported modules to resolve references 1585 1586.. option:: -fmodules-strict-decluse 1587 1588Like -fmodules-decluse but requires all headers to be in modules 1589 1590.. option:: -fmodules-ts 1591 1592Enable support for the C++ Modules TS 1593 1594.. option:: -fms-compatibility, -fno-ms-compatibility 1595 1596Enable full Microsoft Visual C++ compatibility 1597 1598.. option:: -fms-compatibility-version=<arg> 1599 1600Dot-separated value representing the Microsoft compiler version number to report in \_MSC\_VER (0 = don't define it (default)) 1601 1602.. option:: -fms-extensions, -fno-ms-extensions 1603 1604Accept some non-standard constructs supported by the Microsoft compiler 1605 1606.. option:: -fms-memptr-rep=<arg> 1607 1608.. option:: -fms-volatile<arg> 1609 1610.. option:: -fmsc-version=<arg> 1611 1612Microsoft compiler version number to report in \_MSC\_VER (0 = don't define it (default)) 1613 1614.. option:: -fmudflap 1615 1616.. option:: -fmudflapth 1617 1618.. option:: -fnested-functions 1619 1620.. option:: -fnew-alignment=<align>, -fnew-alignment <arg> 1621 1622Specifies the largest alignment guaranteed by '::operator new(size\_t)' 1623 1624.. option:: -fnext-runtime 1625 1626.. option:: -fno-builtin-<arg> 1627 1628Disable implicit builtin knowledge of a specific function 1629 1630.. option:: -fno-elide-type 1631 1632Do not elide types when printing diagnostics 1633 1634.. option:: -fno-max-type-align 1635 1636.. option:: -fno-operator-names 1637 1638Do not treat C++ operator name keywords as synonyms for operators 1639 1640.. option:: -fno-rtti-data 1641 1642Control emission of RTTI data 1643 1644.. option:: -fno-strict-modules-decluse 1645 1646.. option:: -fno-working-directory 1647 1648.. option:: -fnoxray-link-deps 1649 1650.. option:: -fobjc-abi-version=<arg> 1651 1652.. option:: -fobjc-arc, -fno-objc-arc 1653 1654Synthesize retain and release calls for Objective-C pointers 1655 1656.. option:: -fobjc-arc-exceptions, -fno-objc-arc-exceptions 1657 1658Use EH-safe code when synthesizing retains and releases in -fobjc-arc 1659 1660.. option:: -fobjc-exceptions, -fno-objc-exceptions 1661 1662Enable Objective-C exceptions 1663 1664.. option:: -fobjc-infer-related-result-type, -fno-objc-infer-related-result-type 1665 1666.. option:: -fobjc-legacy-dispatch, -fno-objc-legacy-dispatch 1667 1668.. option:: -fobjc-link-runtime 1669 1670.. option:: -fobjc-nonfragile-abi, -fno-objc-nonfragile-abi 1671 1672.. option:: -fobjc-nonfragile-abi-version=<arg> 1673 1674.. option:: -fobjc-runtime=<arg> 1675 1676Specify the target Objective-C runtime kind and version 1677 1678.. option:: -fobjc-sender-dependent-dispatch 1679 1680.. option:: -fobjc-weak, -fno-objc-weak 1681 1682Enable ARC-style weak references in Objective-C 1683 1684.. option:: -fomit-frame-pointer, -fno-omit-frame-pointer 1685 1686.. option:: -fopenmp, -fno-openmp 1687 1688Parse OpenMP pragmas and generate parallel code. 1689 1690.. option:: -fopenmp-simd, -fno-openmp-simd 1691 1692Emit OpenMP code only for SIMD-based constructs. 1693 1694.. option:: -fopenmp-version=<arg> 1695 1696.. program:: clang1 1697.. option:: -fopenmp=<arg> 1698.. program:: clang 1699 1700.. option:: -foperator-arrow-depth=<arg> 1701 1702.. option:: -foptimization-record-file=<arg> 1703 1704Specify the file name of any generated YAML optimization record 1705 1706.. option:: -foptimize-sibling-calls, -fno-optimize-sibling-calls 1707 1708.. option:: -foutput-class-dir=<arg>, --output-class-directory <arg>, --output-class-directory=<arg> 1709 1710.. option:: -fpack-struct, -fno-pack-struct 1711 1712.. program:: clang1 1713.. option:: -fpack-struct=<arg> 1714.. program:: clang 1715 1716Specify the default maximum struct packing alignment 1717 1718.. option:: -fpascal-strings, -fno-pascal-strings, -mpascal-strings 1719 1720Recognize and construct Pascal-style string literals 1721 1722.. option:: -fpcc-struct-return 1723 1724Override the default ABI to return all structs on the stack 1725 1726.. option:: -fpch-preprocess 1727 1728.. option:: -fpic, -fno-pic 1729 1730.. option:: -fpie, -fno-pie 1731 1732.. option:: -fplt, -fno-plt 1733 1734Use the PLT to make function calls 1735 1736.. option:: -fplugin=<dsopath> 1737 1738Load the named plugin (dynamic shared object) 1739 1740.. option:: -fpreserve-as-comments, -fno-preserve-as-comments 1741 1742.. option:: -fprofile-arcs, -fno-profile-arcs 1743 1744.. option:: -fprofile-dir=<arg> 1745 1746.. option:: -fprofile-generate, -fno-profile-generate 1747 1748Generate instrumented code to collect execution counts into default.profraw (overridden by LLVM\_PROFILE\_FILE env var) 1749 1750.. program:: clang1 1751.. option:: -fprofile-generate=<directory> 1752.. program:: clang 1753 1754Generate instrumented code to collect execution counts into <directory>/default.profraw (overridden by LLVM\_PROFILE\_FILE env var) 1755 1756.. option:: -fprofile-instr-generate, -fno-profile-instr-generate 1757 1758Generate instrumented code to collect execution counts into default.profraw file (overridden by '=' form of option or LLVM\_PROFILE\_FILE env var) 1759 1760.. program:: clang1 1761.. option:: -fprofile-instr-generate=<file> 1762.. program:: clang 1763 1764Generate instrumented code to collect execution counts into <file> (overridden by LLVM\_PROFILE\_FILE env var) 1765 1766.. option:: -fprofile-instr-use, -fno-profile-instr-use, -fprofile-use 1767 1768.. program:: clang1 1769.. option:: -fprofile-instr-use=<arg> 1770.. program:: clang 1771 1772Use instrumentation data for profile-guided optimization 1773 1774.. option:: -fprofile-sample-accurate, -fauto-profile-accurate, -fno-profile-sample-accurate 1775 1776Specifies that the sample profile is accurate. If the sample 1777 profile is accurate, callsites without profile samples are marked 1778 as cold. Otherwise, treat callsites without profile samples as if 1779 we have no profile 1780 1781.. option:: -fprofile-sample-use, -fauto-profile, -fno-profile-sample-use 1782 1783.. program:: clang1 1784.. option:: -fprofile-sample-use=<arg>, -fauto-profile=<arg> 1785.. program:: clang 1786 1787Enable sample-based profile guided optimizations 1788 1789.. program:: clang1 1790.. option:: -fprofile-use=<pathname> 1791.. program:: clang 1792 1793Use instrumentation data for profile-guided optimization. If pathname is a directory, it reads from <pathname>/default.profdata. Otherwise, it reads from file <pathname>. 1794 1795.. option:: -freciprocal-math, -fno-reciprocal-math 1796 1797Allow division operations to be reassociated 1798 1799.. option:: -freg-struct-return 1800 1801Override the default ABI to return small structs in registers 1802 1803.. option:: -fregister-global-dtors-with-atexit, -fno-register-global-dtors-with-atexit 1804 1805Use atexit or \_\_cxa\_atexit to register global destructors 1806 1807.. option:: -frelaxed-template-template-args, -fno-relaxed-template-template-args 1808 1809Enable C++17 relaxed template template argument matching 1810 1811.. option:: -freroll-loops, -fno-reroll-loops 1812 1813Turn on loop reroller 1814 1815.. option:: -fretain-comments-from-system-headers 1816 1817.. option:: -frewrite-imports, -fno-rewrite-imports 1818 1819.. option:: -frewrite-includes, -fno-rewrite-includes 1820 1821.. option:: -frewrite-map-file <arg> 1822 1823.. program:: clang1 1824.. option:: -frewrite-map-file=<arg> 1825.. program:: clang 1826 1827.. option:: -fropi, -fno-ropi 1828 1829.. option:: -frtti, -fno-rtti 1830 1831.. option:: -frwpi, -fno-rwpi 1832 1833.. option:: -fsave-optimization-record, -fno-save-optimization-record 1834 1835Generate a YAML optimization record file 1836 1837.. option:: -fseh-exceptions 1838 1839Use SEH style exceptions 1840 1841.. option:: -fshort-enums, -fno-short-enums 1842 1843Allocate to an enum type only as many bytes as it needs for the declared range of possible values 1844 1845.. option:: -fshort-wchar, -fno-short-wchar 1846 1847Force wchar\_t to be a short unsigned int 1848 1849.. option:: -fshow-column, -fno-show-column 1850 1851.. option:: -fshow-overloads=<arg> 1852 1853Which overload candidates to show when overload resolution fails: best\|all; defaults to all 1854 1855.. option:: -fshow-source-location, -fno-show-source-location 1856 1857.. option:: -fsignaling-math, -fno-signaling-math 1858 1859.. option:: -fsigned-bitfields 1860 1861.. option:: -fsigned-char, -fno-signed-char, --signed-char 1862 1863.. option:: -fsigned-zeros, -fno-signed-zeros 1864 1865.. option:: -fsized-deallocation, -fno-sized-deallocation 1866 1867Enable C++14 sized global deallocation functions 1868 1869.. option:: -fsjlj-exceptions 1870 1871Use SjLj style exceptions 1872 1873.. option:: -fslp-vectorize, -fno-slp-vectorize, -ftree-slp-vectorize 1874 1875Enable the superword-level parallelism vectorization passes 1876 1877.. option:: -fspell-checking, -fno-spell-checking 1878 1879.. option:: -fspell-checking-limit=<arg> 1880 1881.. option:: -fsplit-dwarf-inlining, -fno-split-dwarf-inlining 1882 1883Provide minimal debug info in the object/executable to facilitate online symbolication/stack traces in the absence of .dwo/.dwp files when using Split DWARF 1884 1885.. option:: -fsplit-stack 1886 1887.. option:: -fstack-protector, -fno-stack-protector 1888 1889Enable stack protectors for functions potentially vulnerable to stack smashing 1890 1891.. option:: -fstack-protector-all 1892 1893Force the usage of stack protectors for all functions 1894 1895.. option:: -fstack-protector-strong 1896 1897Use a strong heuristic to apply stack protectors to functions 1898 1899.. option:: -fstack-size-section, -fno-stack-size-section 1900 1901Emit section containing metadata on function stack sizes 1902 1903.. option:: -fstandalone-debug, -fno-limit-debug-info, -fno-standalone-debug 1904 1905Emit full debug info for all types used by the program 1906 1907.. option:: -fstrict-aliasing, -fno-strict-aliasing 1908 1909.. option:: -fstrict-enums, -fno-strict-enums 1910 1911Enable optimizations based on the strict definition of an enum's value range 1912 1913.. option:: -fstrict-float-cast-overflow, -fno-strict-float-cast-overflow 1914 1915Assume that overflowing float-to-int casts are undefined (default) 1916 1917.. option:: -fstrict-overflow, -fno-strict-overflow 1918 1919.. option:: -fstrict-return, -fno-strict-return 1920 1921Always treat control flow paths that fall off the end of a non-void function as unreachable 1922 1923.. option:: -fstrict-vtable-pointers, -fno-strict-vtable-pointers 1924 1925Enable optimizations based on the strict rules for overwriting polymorphic C++ objects 1926 1927.. option:: -fstruct-path-tbaa, -fno-struct-path-tbaa 1928 1929.. option:: -ftabstop=<arg> 1930 1931.. option:: -ftemplate-backtrace-limit=<arg> 1932 1933.. option:: -ftemplate-depth-<arg> 1934 1935.. option:: -ftemplate-depth=<arg> 1936 1937.. option:: -ftest-coverage 1938 1939.. option:: -fthinlto-index=<arg> 1940 1941Perform ThinLTO importing using provided function summary index 1942 1943.. option:: -fthreadsafe-statics, -fno-threadsafe-statics 1944 1945.. option:: -ftime-report 1946 1947.. option:: -ftls-model=<arg> 1948 1949.. option:: -ftrap-function=<arg> 1950 1951Issue call to specified function rather than a trap instruction 1952 1953.. option:: -ftrapping-math, -fno-trapping-math 1954 1955.. option:: -ftrapv 1956 1957Trap on integer overflow 1958 1959.. option:: -ftrapv-handler <arg> 1960 1961.. program:: clang1 1962.. option:: -ftrapv-handler=<function name> 1963.. program:: clang 1964 1965Specify the function to be called on overflow 1966 1967.. option:: -ftrigraphs, -fno-trigraphs, -trigraphs, --trigraphs 1968 1969Process trigraph sequences 1970 1971.. option:: -funique-section-names, -fno-unique-section-names 1972 1973Use unique names for text and data sections (ELF Only) 1974 1975.. option:: -funit-at-a-time, -fno-unit-at-a-time 1976 1977.. option:: -funroll-loops, -fno-unroll-loops 1978 1979Turn on loop unroller 1980 1981.. option:: -funsafe-math-optimizations, -fno-unsafe-math-optimizations 1982 1983.. option:: -funsigned-bitfields 1984 1985.. option:: -funsigned-char, -fno-unsigned-char, --unsigned-char 1986 1987.. option:: -funwind-tables, -fno-unwind-tables 1988 1989.. option:: -fuse-cxa-atexit, -fno-use-cxa-atexit 1990 1991.. option:: -fuse-init-array, -fno-use-init-array 1992 1993Use .init\_array instead of .ctors 1994 1995.. option:: -fuse-ld=<arg> 1996 1997.. option:: -fuse-line-directives, -fno-use-line-directives 1998 1999.. option:: -fveclib=<arg> 2000 2001Use the given vector functions library 2002 2003.. option:: -fvectorize, -fno-vectorize, -ftree-vectorize 2004 2005Enable the loop vectorization passes 2006 2007.. option:: -fverbose-asm, -fno-verbose-asm 2008 2009.. option:: -fvisibility-inlines-hidden 2010 2011Give inline C++ member functions hidden visibility by default 2012 2013.. option:: -fvisibility-ms-compat 2014 2015Give global types 'default' visibility and global functions and variables 'hidden' visibility by default 2016 2017.. option:: -fvisibility=<arg> 2018 2019Set the default symbol visibility for all global declarations 2020 2021.. option:: -fwhole-program-vtables, -fno-whole-program-vtables 2022 2023Enables whole-program vtable optimization. Requires -flto 2024 2025.. option:: -fwrapv, -fno-wrapv 2026 2027Treat signed integer overflow as two's complement 2028 2029.. option:: -fwritable-strings 2030 2031Store string literals as writable data 2032 2033.. option:: -fxray-always-emit-customevents, -fno-xray-always-emit-customevents 2034 2035Determine whether to always emit \_\_xray\_customevent(...) calls even if the function it appears in is not always instrumented. 2036 2037.. option:: -fxray-always-emit-typedevents, -fno-xray-always-emit-typedevents 2038 2039Determine whether to always emit \_\_xray\_typedevent(...) calls even if the function it appears in is not always instrumented. 2040 2041.. option:: -fxray-always-instrument=<arg> 2042 2043DEPRECATED: Filename defining the whitelist for imbuing the 'always instrument' XRay attribute. 2044 2045.. option:: -fxray-attr-list=<arg> 2046 2047Filename defining the list of functions/types for imbuing XRay attributes. 2048 2049.. option:: -fxray-instruction-threshold<arg> 2050 2051.. program:: clang1 2052.. option:: -fxray-instruction-threshold=<arg> 2053.. program:: clang 2054 2055Sets the minimum function size to instrument with XRay 2056 2057.. option:: -fxray-instrument, -fno-xray-instrument 2058 2059Generate XRay instrumentation sleds on function entry and exit 2060 2061.. option:: -fxray-instrumentation-bundle=<arg> 2062 2063Select which XRay instrumentation points to emit. Options: all, none, function, custom. Default is 'all'. 2064 2065.. option:: -fxray-link-deps 2066 2067Tells clang to add the link dependencies for XRay. 2068 2069.. option:: -fxray-modes=<arg> 2070 2071List of modes to link in by default into XRay instrumented binaries. 2072 2073.. option:: -fxray-never-instrument=<arg> 2074 2075DEPRECATED: Filename defining the whitelist for imbuing the 'never instrument' XRay attribute. 2076 2077.. option:: -fzero-initialized-in-bss, -fno-zero-initialized-in-bss 2078 2079.. option:: -fzvector, -fno-zvector, -mzvector 2080 2081Enable System z vector language extension 2082 2083.. option:: -pedantic, --pedantic, -no-pedantic, --no-pedantic 2084 2085.. option:: -pedantic-errors, --pedantic-errors 2086 2087OpenCL flags 2088------------ 2089.. option:: -cl-denorms-are-zero 2090 2091OpenCL only. Allow denormals to be flushed to zero. 2092 2093.. option:: -cl-fast-relaxed-math 2094 2095OpenCL only. Sets -cl-finite-math-only and -cl-unsafe-math-optimizations, and defines \_\_FAST\_RELAXED\_MATH\_\_. 2096 2097.. option:: -cl-finite-math-only 2098 2099OpenCL only. Allow floating-point optimizations that assume arguments and results are not NaNs or +-Inf. 2100 2101.. option:: -cl-fp32-correctly-rounded-divide-sqrt 2102 2103OpenCL only. Specify that single precision floating-point divide and sqrt used in the program source are correctly rounded. 2104 2105.. option:: -cl-kernel-arg-info 2106 2107OpenCL only. Generate kernel argument metadata. 2108 2109.. option:: -cl-mad-enable 2110 2111OpenCL only. Allow use of less precise MAD computations in the generated binary. 2112 2113.. option:: -cl-no-signed-zeros 2114 2115OpenCL only. Allow use of less precise no signed zeros computations in the generated binary. 2116 2117.. option:: -cl-opt-disable 2118 2119OpenCL only. This option disables all optimizations. By default optimizations are enabled. 2120 2121.. option:: -cl-single-precision-constant 2122 2123OpenCL only. Treat double precision floating-point constant as single precision constant. 2124 2125.. option:: -cl-std=<arg> 2126 2127OpenCL language standard to compile for. 2128 2129.. option:: -cl-strict-aliasing 2130 2131OpenCL only. This option is added for compatibility with OpenCL 1.0. 2132 2133.. option:: -cl-uniform-work-group-size 2134 2135OpenCL only. Defines that the global work-size be a multiple of the work-group size specified to clEnqueueNDRangeKernel 2136 2137.. option:: -cl-unsafe-math-optimizations 2138 2139OpenCL only. Allow unsafe floating-point optimizations. Also implies -cl-no-signed-zeros and -cl-mad-enable. 2140 2141Target-dependent compilation options 2142~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 2143.. option:: -G<size>, -G=<arg>, -msmall-data-threshold=<arg> 2144 2145Put objects of at most <size> bytes into small data section (MIPS / Hexagon) 2146 2147.. option:: -m16 2148 2149.. option:: -m32 2150 2151.. option:: -m64 2152 2153.. option:: -mabi=<arg> 2154 2155.. option:: -malign-double 2156 2157Align doubles to two words in structs (x86 only) 2158 2159.. option:: -march=<arg> 2160 2161.. option:: -masm=<arg> 2162 2163.. option:: -mbackchain, -mno-backchain 2164 2165Link stack frames through backchain on System Z 2166 2167.. option:: -mcmodel=<arg> 2168 2169.. option:: -mconsole<arg> 2170 2171.. 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) 2172 2173Use -mcpu=? to see a list of supported cpu models. 2174 2175.. option:: -mcrc, -mno-crc 2176 2177Allow use of CRC instructions (ARM/Mips only) 2178 2179.. option:: -mdefault-build-attributes<arg>, -mno-default-build-attributes<arg> 2180 2181.. option:: -mdll<arg> 2182 2183.. option:: -mdynamic-no-pic<arg> 2184 2185.. option:: -meabi <arg> 2186 2187Set EABI type, e.g. 4, 5 or gnu (default depends on triple) 2188 2189.. option:: -mfentry 2190 2191Insert calls to fentry at function entry (x86 only) 2192 2193.. option:: -mfloat-abi=<arg> 2194 2195.. option:: -mfpmath=<arg> 2196 2197.. option:: -mfpu=<arg> 2198 2199.. option:: -mglobal-merge, -mno-global-merge 2200 2201Enable merging of globals 2202 2203.. option:: -mhard-float 2204 2205.. option:: -mhwdiv=<arg>, --mhwdiv <arg>, --mhwdiv=<arg> 2206 2207.. option:: -miamcu, -mno-iamcu 2208 2209Use Intel MCU ABI 2210 2211.. option:: -mimplicit-float, -mno-implicit-float 2212 2213.. option:: -mimplicit-it=<arg> 2214 2215.. option:: -mincremental-linker-compatible, -mno-incremental-linker-compatible 2216 2217(integrated-as) Emit an object file which can be used with an incremental linker 2218 2219.. option:: -miphoneos-version-min=<arg>, -mios-version-min=<arg> 2220 2221.. option:: -mkernel 2222 2223.. option:: -mlong-calls, -mno-long-calls 2224 2225Generate branches with extended addressability, usually via indirect jumps. 2226 2227.. option:: -mmacosx-version-min=<arg>, -mmacos-version-min=<arg> 2228 2229Set macOS deployment target 2230 2231.. option:: -mmcu=<arg> 2232 2233.. option:: -mms-bitfields, -mno-ms-bitfields 2234 2235Set the default structure layout to be compatible with the Microsoft compiler standard 2236 2237.. option:: -momit-leaf-frame-pointer, -mno-omit-leaf-frame-pointer 2238 2239Omit frame pointer setup for leaf functions 2240 2241.. option:: -moslib=<arg> 2242 2243.. option:: -mpie-copy-relocations, -mno-pie-copy-relocations 2244 2245Use copy relocations support for PIE builds 2246 2247.. option:: -mprefer-vector-width=<arg> 2248 2249Specifies preferred vector width for auto-vectorization. Defaults to 'none' which allows target specific decisions. 2250 2251.. option:: -mqdsp6-compat 2252 2253Enable hexagon-qdsp6 backward compatibility 2254 2255.. option:: -mrecip 2256 2257.. program:: clang1 2258.. option:: -mrecip=<arg1>,<arg2>... 2259.. program:: clang 2260 2261.. option:: -mred-zone, -mno-red-zone 2262 2263.. option:: -mregparm=<arg> 2264 2265.. option:: -mrelax-all, -mno-relax-all 2266 2267(integrated-as) Relax all machine instructions 2268 2269.. option:: -mretpoline, -mno-retpoline 2270 2271.. option:: -mrtd, -mno-rtd 2272 2273Make StdCall calling convention the default 2274 2275.. option:: -msign-return-address=<arg> 2276 2277Select return address signing scope 2278 2279.. option:: -msoft-float, -mno-soft-float 2280 2281Use software floating point 2282 2283.. option:: -mstack-alignment=<arg> 2284 2285Set the stack alignment 2286 2287.. option:: -mstack-arg-probe, -mno-stack-arg-probe 2288 2289Enable stack probes 2290 2291.. option:: -mstack-probe-size=<arg> 2292 2293Set the stack probe size 2294 2295.. option:: -mstackrealign, -mno-stackrealign 2296 2297Force realign the stack at entry to every function 2298 2299.. option:: -mthread-model <arg> 2300 2301The thread model to use, e.g. posix, single (posix by default) 2302 2303.. option:: -mthreads<arg> 2304 2305.. option:: -mthumb, -mno-thumb 2306 2307.. option:: -mtune=<arg> 2308 2309Use -mtune=? to see a list of supported cpu models. 2310 2311.. option:: -mtvos-version-min=<arg>, -mappletvos-version-min=<arg> 2312 2313.. option:: -municode<arg> 2314 2315.. option:: -mvx, -mno-vx 2316 2317.. option:: -mwarn-nonportable-cfstrings, -mno-warn-nonportable-cfstrings 2318 2319.. option:: -mwatchos-version-min=<arg> 2320 2321.. option:: -mwindows<arg> 2322 2323.. option:: -mx32 2324 2325AARCH64 2326------- 2327.. option:: -ffixed-x1 2328 2329Reserve the x1 register (AArch64 only) 2330 2331.. option:: -ffixed-x2 2332 2333Reserve the x2 register (AArch64 only) 2334 2335.. option:: -ffixed-x3 2336 2337Reserve the x3 register (AArch64 only) 2338 2339.. option:: -ffixed-x4 2340 2341Reserve the x4 register (AArch64 only) 2342 2343.. option:: -ffixed-x5 2344 2345Reserve the x5 register (AArch64 only) 2346 2347.. option:: -ffixed-x6 2348 2349Reserve the x6 register (AArch64 only) 2350 2351.. option:: -ffixed-x7 2352 2353Reserve the x7 register (AArch64 only) 2354 2355.. option:: -ffixed-x18 2356 2357Reserve the x18 register (AArch64 only) 2358 2359.. option:: -ffixed-x20 2360 2361Reserve the x20 register (AArch64 only) 2362 2363.. option:: -fcall-saved-x8 2364 2365Make the x8 register call-saved (AArch64 only) 2366 2367.. option:: -fcall-saved-x9 2368 2369Make the x9 register call-saved (AArch64 only) 2370 2371.. option:: -fcall-saved-x10 2372 2373Make the x10 register call-saved (AArch64 only) 2374 2375.. option:: -fcall-saved-x11 2376 2377Make the x11 register call-saved (AArch64 only) 2378 2379.. option:: -fcall-saved-x12 2380 2381Make the x12 register call-saved (AArch64 only) 2382 2383.. option:: -fcall-saved-x13 2384 2385Make the x13 register call-saved (AArch64 only) 2386 2387.. option:: -fcall-saved-x14 2388 2389Make the x14 register call-saved (AArch64 only) 2390 2391.. option:: -fcall-saved-x15 2392 2393Make the x15 register call-saved (AArch64 only) 2394 2395.. option:: -fcall-saved-x18 2396 2397Make the x18 register call-saved (AArch64 only) 2398 2399.. option:: -mfix-cortex-a53-835769, -mno-fix-cortex-a53-835769 2400 2401Workaround Cortex-A53 erratum 835769 (AArch64 only) 2402 2403.. option:: -mgeneral-regs-only 2404 2405Generate code which only uses the general purpose registers (AArch64 only) 2406 2407AMDGPU 2408------ 2409.. option:: -mcumode, -mno-cumode 2410 2411CU wavefront execution mode is used if enabled and WGP wavefront execution mode 2412is used if disabled (AMDGPU only) 2413 2414.. option:: -mwavefrontsize64, -mno-wavefrontsize64 2415 2416Wavefront size 64 is used if enabled and wavefront size 32 if disabled (AMDGPU only) 2417 2418.. option:: -mxnack, -mno-xnack 2419 2420Enable XNACK (AMDGPU only) 2421 2422ARM 2423--- 2424.. option:: -ffixed-r9 2425 2426Reserve the r9 register (ARM only) 2427 2428.. option:: -mexecute-only, -mno-execute-only, -mpure-code 2429 2430Disallow generation of data access to code sections (ARM only) 2431 2432.. option:: -mno-movt 2433 2434Disallow use of movt/movw pairs (ARM only) 2435 2436.. option:: -mno-neg-immediates 2437 2438Disallow converting instructions with negative immediates to their negation or inversion. 2439 2440.. option:: -mnocrc 2441 2442Disallow use of CRC instructions (ARM only) 2443 2444.. option:: -mrestrict-it, -mno-restrict-it 2445 2446Disallow generation of deprecated IT blocks for ARMv8. It is on by default for ARMv8 Thumb mode. 2447 2448.. option:: -mtp=<arg> 2449 2450Read thread pointer from coprocessor register (ARM only) 2451 2452.. option:: -munaligned-access, -mno-unaligned-access 2453 2454Allow memory accesses to be unaligned (AArch32/AArch64 only) 2455 2456Hexagon 2457------- 2458.. option:: -mieee-rnd-near 2459 2460.. option:: -mmemops, -mno-memops 2461 2462Enable generation of memop instructions 2463 2464.. option:: -mnvj, -mno-nvj 2465 2466Enable generation of new-value jumps 2467 2468.. option:: -mnvs, -mno-nvs 2469 2470Enable generation of new-value stores 2471 2472.. option:: -mpackets, -mno-packets 2473 2474Enable generation of instruction packets 2475 2476Hexagon 2477------- 2478.. option:: -mhvx, -mno-hvx 2479 2480Enable Hexagon Vector eXtensions 2481 2482.. option:: -mhvx-length=<arg> 2483 2484Set Hexagon Vector Length 2485 2486.. program:: clang1 2487.. option:: -mhvx=<arg> 2488.. program:: clang 2489 2490Enable Hexagon Vector eXtensions 2491 2492MIPS 2493---- 2494.. option:: -mabicalls, -mno-abicalls 2495 2496Enable SVR4-style position-independent code (Mips only) 2497 2498.. option:: -mabs=<arg> 2499 2500.. option:: -mcheck-zero-division, -mno-check-zero-division 2501 2502.. option:: -mcompact-branches=<arg> 2503 2504.. option:: -mdouble-float 2505 2506.. option:: -mdsp, -mno-dsp 2507 2508.. option:: -mdspr2, -mno-dspr2 2509 2510.. option:: -membedded-data, -mno-embedded-data 2511 2512Place constants in the .rodata section instead of the .sdata section even if they meet the -G <size> threshold (MIPS) 2513 2514.. option:: -mextern-sdata, -mno-extern-sdata 2515 2516Assume that externally defined data is in the small data if it meets the -G <size> threshold (MIPS) 2517 2518.. option:: -mfp32 2519 2520Use 32-bit floating point registers (MIPS only) 2521 2522.. option:: -mfp64 2523 2524Use 64-bit floating point registers (MIPS only) 2525 2526.. option:: -mginv, -mno-ginv 2527 2528.. option:: -mgpopt, -mno-gpopt 2529 2530Use GP relative accesses for symbols known to be in a small data section (MIPS) 2531 2532.. option:: -mindirect-jump=<arg> 2533 2534Change indirect jump instructions to inhibit speculation 2535 2536.. option:: -mips16 2537 2538.. option:: -mldc1-sdc1, -mno-ldc1-sdc1 2539 2540.. option:: -mlocal-sdata, -mno-local-sdata 2541 2542Extend the -G behaviour to object local data (MIPS) 2543 2544.. option:: -mmadd4, -mno-madd4 2545 2546Enable the generation of 4-operand madd.s, madd.d and related instructions. 2547 2548.. option:: -mmicromips, -mno-micromips 2549 2550.. option:: -mmsa, -mno-msa 2551 2552Enable MSA ASE (MIPS only) 2553 2554.. option:: -mmt, -mno-mt 2555 2556Enable MT ASE (MIPS only) 2557 2558.. option:: -mnan=<arg> 2559 2560.. option:: -mno-mips16 2561 2562.. option:: -msingle-float 2563 2564.. option:: -mvirt, -mno-virt 2565 2566.. option:: -mxgot, -mno-xgot 2567 2568PowerPC 2569------- 2570.. option:: -maltivec, -mno-altivec 2571 2572.. option:: -mcmpb, -mno-cmpb 2573 2574.. option:: -mcrbits, -mno-crbits 2575 2576.. option:: -mcrypto, -mno-crypto 2577 2578.. option:: -mdirect-move, -mno-direct-move 2579 2580.. option:: -mfloat128, -mno-float128 2581 2582.. option:: -mfprnd, -mno-fprnd 2583 2584.. option:: -mhtm, -mno-htm 2585 2586.. option:: -minvariant-function-descriptors, -mno-invariant-function-descriptors 2587 2588.. option:: -misel, -mno-isel 2589 2590.. option:: -mlongcall, -mno-longcall 2591 2592.. option:: -mmfocrf, -mmfcrf, -mno-mfocrf 2593 2594.. option:: -mpopcntd, -mno-popcntd 2595 2596.. option:: -mpower8-vector, -mno-power8-vector 2597 2598.. option:: -mpower9-vector, -mno-power9-vector 2599 2600.. option:: -mqpx, -mno-qpx 2601 2602.. option:: -msecure-plt 2603 2604.. option:: -mvsx, -mno-vsx 2605 2606WebAssembly 2607----------- 2608.. option:: -mexception-handling, -mno-exception-handling 2609 2610.. option:: -mnontrapping-fptoint, -mno-nontrapping-fptoint 2611 2612.. option:: -msign-ext, -mno-sign-ext 2613 2614.. option:: -msimd128, -mno-simd128 2615 2616X86 2617--- 2618.. option:: -m3dnow, -mno-3dnow 2619 2620.. option:: -m3dnowa, -mno-3dnowa 2621 2622.. option:: -madx, -mno-adx 2623 2624.. option:: -maes, -mno-aes 2625 2626.. option:: -mavx, -mno-avx 2627 2628.. option:: -mavx2, -mno-avx2 2629 2630.. option:: -mavx512bitalg, -mno-avx512bitalg 2631 2632.. option:: -mavx512bf16, -mno-avx512bf16 2633 2634.. option:: -mavx512bw, -mno-avx512bw 2635 2636.. option:: -mavx512cd, -mno-avx512cd 2637 2638.. option:: -mavx512dq, -mno-avx512dq 2639 2640.. option:: -mavx512er, -mno-avx512er 2641 2642.. option:: -mavx512f, -mno-avx512f 2643 2644.. option:: -mavx512ifma, -mno-avx512ifma 2645 2646.. option:: -mavx512pf, -mno-avx512pf 2647 2648.. option:: -mavx512vbmi, -mno-avx512vbmi 2649 2650.. option:: -mavx512vbmi2, -mno-avx512vbmi2 2651 2652.. option:: -mavx512vl, -mno-avx512vl 2653 2654.. option:: -mavx512vnni, -mno-avx512vnni 2655 2656.. option:: -mavx512vp2intersect, -mno-avx512vp2intersect 2657 2658.. option:: -mavx512vpopcntdq, -mno-avx512vpopcntdq 2659 2660.. option:: -mbmi, -mno-bmi 2661 2662.. option:: -mbmi2, -mno-bmi2 2663 2664.. option:: -mcldemote, -mno-cldemote 2665 2666.. option:: -mclflushopt, -mno-clflushopt 2667 2668.. option:: -mclwb, -mno-clwb 2669 2670.. option:: -mclzero, -mno-clzero 2671 2672.. option:: -mcx16, -mno-cx16 2673 2674.. option:: -menqcmd, -mno-enqcmd 2675 2676.. option:: -mf16c, -mno-f16c 2677 2678.. option:: -mfma, -mno-fma 2679 2680.. option:: -mfma4, -mno-fma4 2681 2682.. option:: -mfsgsbase, -mno-fsgsbase 2683 2684.. option:: -mfxsr, -mno-fxsr 2685 2686.. option:: -mgfni, -mno-gfni 2687 2688.. option:: -minvpcid, -mno-invpcid 2689 2690.. option:: -mlwp, -mno-lwp 2691 2692.. option:: -mlzcnt, -mno-lzcnt 2693 2694.. option:: -mmmx, -mno-mmx 2695 2696.. option:: -mmovbe, -mno-movbe 2697 2698.. option:: -mmovdir64b, -mno-movdir64b 2699 2700.. option:: -mmovdiri, -mno-movdiri 2701 2702.. option:: -mmpx, -mno-mpx 2703 2704.. option:: -mmwaitx, -mno-mwaitx 2705 2706.. option:: -mpclmul, -mno-pclmul 2707 2708.. option:: -mpconfig, -mno-pconfig 2709 2710.. option:: -mpku, -mno-pku 2711 2712.. option:: -mpopcnt, -mno-popcnt 2713 2714.. option:: -mprefetchwt1, -mno-prefetchwt1 2715 2716.. option:: -mprfchw, -mno-prfchw 2717 2718.. option:: -mptwrite, -mno-ptwrite 2719 2720.. option:: -mrdpid, -mno-rdpid 2721 2722.. option:: -mrdrnd, -mno-rdrnd 2723 2724.. option:: -mrdseed, -mno-rdseed 2725 2726.. option:: -mretpoline-external-thunk, -mno-retpoline-external-thunk 2727 2728.. option:: -mrtm, -mno-rtm 2729 2730.. option:: -msahf, -mno-sahf 2731 2732.. option:: -msgx, -mno-sgx 2733 2734.. option:: -msha, -mno-sha 2735 2736.. option:: -mshstk, -mno-shstk 2737 2738.. option:: -msse, -mno-sse 2739 2740.. option:: -msse2, -mno-sse2 2741 2742.. option:: -msse3, -mno-sse3 2743 2744.. option:: -msse4.1, -mno-sse4.1 2745 2746.. program:: clang1 2747.. option:: -msse4.2, -mno-sse4.2, -msse4 2748.. program:: clang 2749 2750.. option:: -msse4a, -mno-sse4a 2751 2752.. option:: -mssse3, -mno-ssse3 2753 2754.. option:: -mtbm, -mno-tbm 2755 2756.. option:: -mvaes, -mno-vaes 2757 2758.. option:: -mvpclmulqdq, -mno-vpclmulqdq 2759 2760.. option:: -mwaitpkg, -mno-waitpkg 2761 2762.. option:: -mwbnoinvd, -mno-wbnoinvd 2763 2764.. option:: -mx87, -m80387, -mno-x87 2765 2766.. option:: -mxop, -mno-xop 2767 2768.. option:: -mxsave, -mno-xsave 2769 2770.. option:: -mxsavec, -mno-xsavec 2771 2772.. option:: -mxsaveopt, -mno-xsaveopt 2773 2774.. option:: -mxsaves, -mno-xsaves 2775 2776RISCV 2777----- 2778.. option:: -mrelax, -mno-relax 2779 2780Enable linker relaxation 2781 2782Optimization level 2783~~~~~~~~~~~~~~~~~~ 2784 2785Flags controlling how much optimization should be performed. 2786 2787.. option:: -O<arg>, -O (equivalent to -O2), --optimize, --optimize=<arg> 2788 2789.. option:: -Ofast<arg> 2790 2791Debug information generation 2792~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 2793 2794Flags controlling how much and what kind of debug information should be 2795generated. 2796 2797Kind and level of debug information 2798----------------------------------- 2799.. option:: -g, --debug, --debug=<arg> 2800 2801Generate source-level debug information 2802 2803.. option:: -gdwarf-2 2804 2805Generate source-level debug information with dwarf version 2 2806 2807.. option:: -gdwarf-3 2808 2809Generate source-level debug information with dwarf version 3 2810 2811.. option:: -gdwarf-4, -gdwarf 2812 2813Generate source-level debug information with dwarf version 4 2814 2815.. option:: -gdwarf-5 2816 2817Generate source-level debug information with dwarf version 5 2818 2819.. option:: -gfull 2820 2821.. option:: -gused 2822 2823Debug level 2824___________ 2825.. option:: -g0 2826 2827.. option:: -g2 2828 2829.. option:: -g3 2830 2831.. option:: -ggdb0 2832 2833.. option:: -ggdb1 2834 2835.. option:: -ggdb2 2836 2837.. option:: -ggdb3 2838 2839.. option:: -gline-tables-only, -g1, -gmlt 2840 2841Emit debug line number tables only 2842 2843.. option:: -gmodules 2844 2845Generate debug info with external references to clang modules or precompiled headers 2846 2847Debugger to tune debug information for 2848______________________________________ 2849.. option:: -ggdb 2850 2851.. option:: -glldb 2852 2853.. option:: -gsce 2854 2855Debug information flags 2856----------------------- 2857.. option:: -gcolumn-info, -gno-column-info 2858 2859.. option:: -gdwarf-aranges 2860 2861.. option:: -gembed-source, -gno-embed-source 2862 2863Embed source text in DWARF debug sections 2864 2865.. option:: -ggnu-pubnames, -gno-gnu-pubnames 2866 2867.. option:: -gpubnames, -gno-pubnames 2868 2869.. option:: -grecord-command-line, -grecord-gcc-switches, -gno-record-command-line, -gno-record-gcc-switches 2870 2871.. option:: -gsplit-dwarf 2872 2873.. option:: -gstrict-dwarf, -gno-strict-dwarf 2874 2875.. option:: -gz 2876 2877DWARF debug sections compression type 2878 2879.. program:: clang1 2880.. option:: -gz=<arg> 2881.. program:: clang 2882 2883DWARF debug sections compression type 2884 2885Static analyzer flags 2886===================== 2887 2888Flags controlling the behavior of the Clang Static Analyzer. 2889 2890.. option:: -Xanalyzer <arg> 2891 2892Pass <arg> to the static analyzer 2893 2894Fortran compilation flags 2895========================= 2896 2897Flags that will be passed onto the ``gfortran`` compiler when Clang is given 2898a Fortran input. 2899 2900.. option:: -A<arg>, --assert <arg>, --assert=<arg> 2901 2902.. option:: -A-<arg> 2903 2904.. option:: -J<arg> 2905 2906.. option:: -cpp 2907 2908.. option:: -faggressive-function-elimination, -fno-aggressive-function-elimination 2909 2910.. option:: -falign-commons, -fno-align-commons 2911 2912.. option:: -fall-intrinsics, -fno-all-intrinsics 2913 2914.. option:: -fautomatic, -fno-automatic 2915 2916.. option:: -fbackslash, -fno-backslash 2917 2918.. option:: -fbacktrace, -fno-backtrace 2919 2920.. option:: -fblas-matmul-limit=<arg> 2921 2922.. option:: -fbounds-check, -fno-bounds-check 2923 2924.. option:: -fcheck-array-temporaries, -fno-check-array-temporaries 2925 2926.. option:: -fcheck=<arg> 2927 2928.. option:: -fcoarray=<arg> 2929 2930.. option:: -fconvert=<arg> 2931 2932.. option:: -fcray-pointer, -fno-cray-pointer 2933 2934.. option:: -fd-lines-as-code, -fno-d-lines-as-code 2935 2936.. option:: -fd-lines-as-comments, -fno-d-lines-as-comments 2937 2938.. option:: -fdefault-double-8, -fno-default-double-8 2939 2940.. option:: -fdefault-integer-8, -fno-default-integer-8 2941 2942.. option:: -fdefault-real-8, -fno-default-real-8 2943 2944.. option:: -fdollar-ok, -fno-dollar-ok 2945 2946.. option:: -fdump-fortran-optimized, -fno-dump-fortran-optimized 2947 2948.. option:: -fdump-fortran-original, -fno-dump-fortran-original 2949 2950.. option:: -fdump-parse-tree, -fno-dump-parse-tree 2951 2952.. option:: -fexternal-blas, -fno-external-blas 2953 2954.. option:: -ff2c, -fno-f2c 2955 2956.. option:: -ffixed-form, -fno-fixed-form 2957 2958.. option:: -ffixed-line-length-<arg> 2959 2960.. option:: -ffpe-trap=<arg> 2961 2962.. option:: -ffree-form, -fno-free-form 2963 2964.. option:: -ffree-line-length-<arg> 2965 2966.. option:: -ffrontend-optimize, -fno-frontend-optimize 2967 2968.. option:: -fimplicit-none, -fno-implicit-none 2969 2970.. option:: -finit-character=<arg> 2971 2972.. option:: -finit-integer=<arg> 2973 2974.. option:: -finit-local-zero, -fno-init-local-zero 2975 2976.. option:: -finit-logical=<arg> 2977 2978.. option:: -finit-real=<arg> 2979 2980.. option:: -finteger-4-integer-8, -fno-integer-4-integer-8 2981 2982.. option:: -fintrinsic-modules-path, -fno-intrinsic-modules-path 2983 2984.. option:: -fmax-array-constructor=<arg> 2985 2986.. option:: -fmax-errors=<arg> 2987 2988.. option:: -fmax-identifier-length, -fno-max-identifier-length 2989 2990.. option:: -fmax-stack-var-size=<arg> 2991 2992.. option:: -fmax-subrecord-length=<arg> 2993 2994.. option:: -fmodule-private, -fno-module-private 2995 2996.. option:: -fpack-derived, -fno-pack-derived 2997 2998.. option:: -fprotect-parens, -fno-protect-parens 2999 3000.. option:: -frange-check, -fno-range-check 3001 3002.. option:: -freal-4-real-10, -fno-real-4-real-10 3003 3004.. option:: -freal-4-real-16, -fno-real-4-real-16 3005 3006.. option:: -freal-4-real-8, -fno-real-4-real-8 3007 3008.. option:: -freal-8-real-10, -fno-real-8-real-10 3009 3010.. option:: -freal-8-real-16, -fno-real-8-real-16 3011 3012.. option:: -freal-8-real-4, -fno-real-8-real-4 3013 3014.. option:: -frealloc-lhs, -fno-realloc-lhs 3015 3016.. option:: -frecord-marker=<arg> 3017 3018.. option:: -frecursive, -fno-recursive 3019 3020.. option:: -frepack-arrays, -fno-repack-arrays 3021 3022.. option:: -fsecond-underscore, -fno-second-underscore 3023 3024.. option:: -fsign-zero, -fno-sign-zero 3025 3026.. option:: -fstack-arrays, -fno-stack-arrays 3027 3028.. option:: -funderscoring, -fno-underscoring 3029 3030.. option:: -fwhole-file, -fno-whole-file 3031 3032.. option:: -imultilib <arg> 3033 3034.. option:: -nocpp 3035 3036.. option:: -static-libgfortran 3037 3038Linker flags 3039============ 3040Flags that are passed on to the linker 3041 3042.. option:: -L<dir>, --library-directory <arg>, --library-directory=<arg> 3043 3044Add directory to library search path 3045 3046.. option:: -Mach 3047 3048.. option:: -T<script> 3049 3050Specify <script> as linker script 3051 3052.. option:: -Tbss<addr> 3053 3054Set starting address of BSS to <addr> 3055 3056.. option:: -Tdata<addr> 3057 3058Set starting address of DATA to <addr> 3059 3060.. option:: -Ttext<addr> 3061 3062Set starting address of TEXT to <addr> 3063 3064.. option:: -Wl,<arg>,<arg2>... 3065 3066Pass the comma separated arguments in <arg> to the linker 3067 3068.. option:: -X 3069 3070.. option:: -Xlinker <arg>, --for-linker <arg>, --for-linker=<arg> 3071 3072Pass <arg> to the linker 3073 3074.. program:: clang1 3075.. option:: -Z 3076.. program:: clang 3077 3078.. option:: -e<arg>, --entry 3079 3080.. option:: -filelist <arg> 3081 3082.. option:: --hip-device-lib-path=<arg> 3083 3084HIP device library path 3085 3086.. option:: --hip-device-lib=<arg> 3087 3088HIP device library 3089 3090.. option:: -l<arg> 3091 3092.. option:: -r 3093 3094.. option:: -rpath <arg> 3095 3096.. option:: -s 3097 3098.. option:: -t 3099 3100.. option:: -u<arg>, --force-link <arg>, --force-link=<arg> 3101 3102.. option:: -undef 3103 3104undef all system defines 3105 3106.. option:: -undefined<arg>, --no-undefined 3107 3108.. option:: -z <arg> 3109 3110Pass -z <arg> to the linker 3111 3112