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