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:: --analyzer-no-default-checks 90 91.. option:: --analyzer-output<arg> 92 93Static analyzer report output format (html\|plist\|plist-multi-file\|plist-html\|text). 94 95.. option:: -ansi, --ansi 96 97.. option:: -arch <arg> 98 99.. program:: clang1 100.. option:: -arch\_errors\_fatal 101.. program:: clang 102 103.. program:: clang2 104.. option:: -arch\_only <arg> 105.. program:: clang 106 107.. option:: -arcmt-migrate-emit-errors 108 109Emit ARC errors even if the migrator can fix them 110 111.. option:: -arcmt-migrate-report-output <arg> 112 113Output path for the plist report 114 115.. option:: --autocomplete=<arg> 116 117.. option:: -bind\_at\_load 118 119.. option:: -bundle 120 121.. program:: clang1 122.. option:: -bundle\_loader <arg> 123.. program:: clang 124 125.. option:: -cfguard 126 127Emit tables and checks for Windows Control Flow Guard. 128 129.. option:: -cfguard-no-checks 130 131Emit tables required for Windows Control Flow Guard without checks. 132 133.. option:: -client\_name<arg> 134 135.. option:: -compatibility\_version<arg> 136 137.. option:: --config <arg> 138 139Specifies configuration file 140 141.. option:: --constant-cfstrings 142 143.. option:: -coverage, --coverage 144 145.. option:: --cuda-compile-host-device 146 147Compile CUDA code for both host and device (default). Has no effect on non-CUDA compilations. 148 149.. option:: --cuda-device-only 150 151Compile CUDA code for device only 152 153.. option:: --cuda-gpu-arch=<arg>, --no-cuda-gpu-arch=<arg> 154 155CUDA GPU architecture (e.g. sm\_35). May be specified more than once. 156 157.. option:: --cuda-host-only 158 159Compile CUDA code for host only. Has no effect on non-CUDA compilations. 160 161.. option:: --cuda-include-ptx=<arg>, --no-cuda-include-ptx=<arg> 162 163Include PTX for the following GPU architecture (e.g. sm\_35) or 'all'. May be specified more than once. 164 165.. option:: --cuda-noopt-device-debug, --no-cuda-noopt-device-debug 166 167Enable device-side debug info generation. Disables ptxas optimizations. 168 169.. option:: -current\_version<arg> 170 171.. option:: -dead\_strip 172 173.. option:: -dependency-dot <arg> 174 175Filename to write DOT-formatted header dependencies to 176 177.. option:: -dependency-file <arg> 178 179Filename (or -) to write dependency output to 180 181.. option:: -dumpmachine 182 183.. option:: -dumpversion 184 185.. option:: --dyld-prefix=<arg>, --dyld-prefix <arg> 186 187.. option:: -dylib\_file <arg> 188 189.. option:: -dylinker 190 191.. program:: clang1 192.. option:: -dylinker\_install\_name<arg> 193.. program:: clang 194 195.. option:: -dynamic 196 197.. option:: -dynamiclib 198 199.. option:: -emit-ast 200 201Emit Clang AST files for source inputs 202 203.. option:: -exported\_symbols\_list <arg> 204 205.. option:: -faligned-new=<arg> 206 207.. option:: -fcuda-approx-transcendentals, -fno-cuda-approx-transcendentals 208 209Use approximate transcendental functions 210 211.. option:: -fcuda-flush-denormals-to-zero, -fno-cuda-flush-denormals-to-zero 212 213Flush denormal floating point values to zero in CUDA device mode. 214 215.. option:: -fcuda-rdc, -fno-cuda-rdc 216 217Generate relocatable device code, also known as separate compilation mode. 218 219.. option:: -fcuda-short-ptr, -fno-cuda-short-ptr 220 221Use 32-bit pointers for accessing const/local/shared address spaces. 222 223.. option:: -ffixed-r19 224 225Reserve register r19 (Hexagon only) 226 227.. option:: -fheinous-gnu-extensions 228 229.. option:: -flat\_namespace 230 231.. option:: -fopenmp-targets=<arg1>,<arg2>... 232 233Specify comma-separated list of triples OpenMP offloading targets to be supported 234 235.. option:: -force\_cpusubtype\_ALL 236 237.. program:: clang1 238.. option:: -force\_flat\_namespace 239.. program:: clang 240 241.. program:: clang2 242.. option:: -force\_load <arg> 243.. program:: clang 244 245.. option:: -framework <arg> 246 247.. option:: -frtlib-add-rpath, -fno-rtlib-add-rpath 248 249Add -rpath with architecture-specific resource directory to the linker flags 250 251.. option:: --gcc-toolchain=<arg>, -gcc-toolchain <arg> 252 253Use the gcc toolchain at the given directory 254 255.. option:: -gcodeview 256 257Generate CodeView debug information 258 259.. option:: -headerpad\_max\_install\_names<arg> 260 261.. option:: -help, --help 262 263Display available options 264 265.. option:: --help-hidden 266 267Display help for hidden options 268 269.. option:: --hip-link 270 271Link clang-offload-bundler bundles for HIP 272 273.. option:: -image\_base <arg> 274 275.. option:: -index-header-map 276 277Make the next included directory (-I or -F) an indexer header map 278 279.. option:: -init <arg> 280 281.. option:: -install\_name <arg> 282 283.. option:: -keep\_private\_externs 284 285.. option:: -lazy\_framework <arg> 286 287.. program:: clang1 288.. option:: -lazy\_library <arg> 289.. program:: clang 290 291.. option:: -mbig-endian, -EB 292 293.. option:: --migrate 294 295Run the migrator 296 297.. option:: -mios-simulator-version-min=<arg>, -miphonesimulator-version-min=<arg> 298 299.. option:: -mlinker-version=<arg> 300 301.. option:: -mlittle-endian, -EL 302 303.. option:: -mllvm <arg> 304 305Additional arguments to forward to LLVM's option processing 306 307.. option:: -module-dependency-dir <arg> 308 309Directory to dump module dependencies to 310 311.. option:: -mtvos-simulator-version-min=<arg>, -mappletvsimulator-version-min=<arg> 312 313.. option:: -multi\_module 314 315.. option:: -multiply\_defined <arg> 316 317.. program:: clang1 318.. option:: -multiply\_defined\_unused <arg> 319.. program:: clang 320 321.. option:: -mwatchos-simulator-version-min=<arg>, -mwatchsimulator-version-min=<arg> 322 323.. option:: --no-cuda-version-check 324 325Don't error out if the detected version of the CUDA install is too low for the requested CUDA gpu architecture. 326 327.. option:: -no-integrated-cpp, --no-integrated-cpp 328 329.. option:: -no\_dead\_strip\_inits\_and\_terms 330 331.. option:: -nobuiltininc 332 333Disable builtin #include directories 334 335.. option:: -nocudainc 336 337.. option:: -nocudalib 338 339.. option:: -nodefaultlibs 340 341.. option:: -nofixprebinding 342 343.. option:: -nolibc 344 345.. option:: -nomultidefs 346 347.. option:: -nopie, -no-pie 348 349.. option:: -noprebind 350 351.. option:: -noprofilelib 352 353.. option:: -noseglinkedit 354 355.. option:: -nostartfiles 356 357.. option:: -nostdinc, --no-standard-includes 358 359.. program:: clang1 360.. option:: -nostdinc++ 361.. program:: clang 362 363Disable standard #include directories for the C++ standard library 364 365.. option:: -nostdlib, --no-standard-libraries 366 367.. program:: clang1 368.. option:: -nostdlib++ 369.. program:: clang 370 371.. option:: -nostdlibinc 372 373.. option:: -o<file>, --output <arg>, --output=<arg> 374 375Write output to <file> 376 377.. option:: -objcmt-atomic-property 378 379Make migration to 'atomic' properties 380 381.. option:: -objcmt-migrate-all 382 383Enable migration to modern ObjC 384 385.. option:: -objcmt-migrate-annotation 386 387Enable migration to property and method annotations 388 389.. option:: -objcmt-migrate-designated-init 390 391Enable migration to infer NS\_DESIGNATED\_INITIALIZER for initializer methods 392 393.. option:: -objcmt-migrate-instancetype 394 395Enable migration to infer instancetype for method result type 396 397.. option:: -objcmt-migrate-literals 398 399Enable migration to modern ObjC literals 400 401.. option:: -objcmt-migrate-ns-macros 402 403Enable migration to NS\_ENUM/NS\_OPTIONS macros 404 405.. option:: -objcmt-migrate-property 406 407Enable migration to modern ObjC property 408 409.. option:: -objcmt-migrate-property-dot-syntax 410 411Enable migration of setter/getter messages to property-dot syntax 412 413.. option:: -objcmt-migrate-protocol-conformance 414 415Enable migration to add protocol conformance on classes 416 417.. option:: -objcmt-migrate-readonly-property 418 419Enable migration to modern ObjC readonly property 420 421.. option:: -objcmt-migrate-readwrite-property 422 423Enable migration to modern ObjC readwrite property 424 425.. option:: -objcmt-migrate-subscripting 426 427Enable migration to modern ObjC subscripting 428 429.. option:: -objcmt-ns-nonatomic-iosonly 430 431Enable migration to use NS\_NONATOMIC\_IOSONLY macro for setting property's 'atomic' attribute 432 433.. option:: -objcmt-returns-innerpointer-property 434 435Enable migration to annotate property with NS\_RETURNS\_INNER\_POINTER 436 437.. option:: -objcmt-whitelist-dir-path=<arg>, -objcmt-white-list-dir-path=<arg> 438 439Only modify files with a filename contained in the provided directory path 440 441.. option:: -object 442 443.. option:: -p, --profile 444 445.. option:: -pagezero\_size<arg> 446 447.. option:: -pg 448 449Enable mcount instrumentation 450 451.. option:: -pie 452 453.. option:: -pipe, --pipe 454 455Use pipes between commands, when possible 456 457.. option:: -prebind 458 459.. program:: clang1 460.. option:: -prebind\_all\_twolevel\_modules 461.. program:: clang 462 463.. option:: -preload 464 465.. option:: --print-diagnostic-categories 466 467.. option:: -print-effective-triple, --print-effective-triple 468 469Print the effective target triple 470 471.. option:: -print-file-name=<file>, --print-file-name=<file>, --print-file-name <arg> 472 473Print the full library path of <file> 474 475.. option:: -print-ivar-layout 476 477Enable Objective-C Ivar layout bitmap print trace 478 479.. option:: -print-libgcc-file-name, --print-libgcc-file-name 480 481Print the library path for the currently used compiler runtime library ("libgcc.a" or "libclang\_rt.builtins.\*.a") 482 483.. option:: -print-multi-directory, --print-multi-directory 484 485.. option:: -print-multi-lib, --print-multi-lib 486 487.. option:: -print-prog-name=<name>, --print-prog-name=<name>, --print-prog-name <arg> 488 489Print the full program path of <name> 490 491.. option:: -print-resource-dir, --print-resource-dir 492 493Print the resource directory pathname 494 495.. option:: -print-search-dirs, --print-search-dirs 496 497Print the paths used for finding libraries and programs 498 499.. option:: -print-target-triple, --print-target-triple 500 501Print the normalized target triple 502 503.. option:: -private\_bundle 504 505.. option:: -pthread, -no-pthread 506 507Support POSIX threads in generated code 508 509.. option:: -pthreads 510 511.. option:: -rdynamic 512 513.. option:: -read\_only\_relocs <arg> 514 515.. option:: -relocatable-pch, --relocatable-pch 516 517Whether to build a relocatable precompiled header 518 519.. option:: -remap 520 521.. option:: -rewrite-legacy-objc 522 523Rewrite Legacy Objective-C source to C++ 524 525.. option:: -rtlib=<arg>, --rtlib=<arg>, --rtlib <arg> 526 527Compiler runtime library to use 528 529.. option:: -save-stats=<arg>, --save-stats=<arg>, -save-stats (equivalent to -save-stats=cwd), --save-stats (equivalent to -save-stats=cwd) 530 531Save llvm statistics. 532 533.. option:: -save-temps=<arg>, --save-temps=<arg>, -save-temps (equivalent to -save-temps=cwd), --save-temps (equivalent to -save-temps=cwd) 534 535Save intermediate compilation results. 536 537.. option:: -sectalign <arg1> <arg2> <arg3> 538 539.. option:: -sectcreate <arg1> <arg2> <arg3> 540 541.. option:: -sectobjectsymbols <arg1> <arg2> 542 543.. option:: -sectorder <arg1> <arg2> <arg3> 544 545.. option:: -seg1addr<arg> 546 547.. option:: -seg\_addr\_table <arg> 548 549.. program:: clang1 550.. option:: -seg\_addr\_table\_filename <arg> 551.. program:: clang 552 553.. option:: -segaddr <arg1> <arg2> 554 555.. option:: -segcreate <arg1> <arg2> <arg3> 556 557.. option:: -seglinkedit 558 559.. option:: -segprot <arg1> <arg2> <arg3> 560 561.. option:: -segs\_read\_<arg> 562 563.. program:: clang1 564.. option:: -segs\_read\_only\_addr <arg> 565.. program:: clang 566 567.. program:: clang2 568.. option:: -segs\_read\_write\_addr <arg> 569.. program:: clang 570 571.. option:: -serialize-diagnostics <arg>, --serialize-diagnostics <arg> 572 573Serialize compiler diagnostics to a file 574 575.. option:: -shared, --shared 576 577.. option:: -shared-libgcc 578 579.. option:: -shared-libsan, -shared-libasan 580 581Dynamically link the sanitizer runtime 582 583.. option:: -single\_module 584 585.. option:: -specs=<arg>, --specs=<arg> 586 587.. option:: -static, --static 588 589.. option:: -static-libgcc 590 591.. option:: -static-libsan 592 593Statically link the sanitizer runtime 594 595.. option:: -static-libstdc++ 596 597.. option:: -std-default=<arg> 598 599.. option:: -stdlib=<arg>, --stdlib=<arg>, --stdlib <arg> 600 601C++ standard library to use 602 603.. option:: -sub\_library<arg> 604 605.. program:: clang1 606.. option:: -sub\_umbrella<arg> 607.. program:: clang 608 609.. option:: --sysroot=<arg>, --sysroot <arg> 610 611.. option:: --target-help 612 613.. option:: --target=<arg>, -target <arg> 614 615Generate code for the given target 616 617.. option:: --print-supported-cpus 618 619Print supported cpu models for the given target 620 621.. option:: -time 622 623Time individual commands 624 625.. option:: -traditional, --traditional 626 627.. option:: -traditional-cpp, --traditional-cpp 628 629Enable some traditional CPP emulation 630 631.. option:: -twolevel\_namespace 632 633.. program:: clang1 634.. option:: -twolevel\_namespace\_hints 635.. program:: clang 636 637.. option:: -umbrella <arg> 638 639.. option:: -unexported\_symbols\_list <arg> 640 641.. option:: -v, --verbose 642 643Show commands to run and use verbose output 644 645.. option:: --verify-debug-info 646 647Verify the binary representation of debug output 648 649.. option:: --version 650 651Print version information 652 653.. option:: -w, --no-warnings 654 655Suppress all warnings 656 657.. option:: -weak-l<arg> 658 659.. option:: -weak\_framework <arg> 660 661.. program:: clang1 662.. option:: -weak\_library <arg> 663.. program:: clang 664 665.. program:: clang2 666.. option:: -weak\_reference\_mismatches <arg> 667.. program:: clang 668 669.. option:: -whatsloaded 670 671.. option:: -whyload 672 673.. option:: -working-directory<arg>, -working-directory=<arg> 674 675Resolve file paths relative to the specified directory 676 677.. option:: -x<language>, --language <arg>, --language=<arg> 678 679Treat subsequent input files as having type <language> 680 681.. option:: -y<arg> 682 683Actions 684======= 685The action to perform on the input. 686 687.. option:: -E, --preprocess 688 689Only run the preprocessor 690 691.. option:: -S, --assemble 692 693Only run preprocess and compilation steps 694 695.. option:: -c, --compile 696 697Only run preprocess, compile, and assemble steps 698 699.. option:: -emit-llvm 700 701Use the LLVM representation for assembler and object files 702 703.. option:: -fsyntax-only 704 705.. option:: -module-file-info 706 707Provide information about a particular module file 708 709.. option:: --precompile 710 711Only precompile the input 712 713.. option:: -rewrite-objc 714 715Rewrite Objective-C source to C++ 716 717.. option:: -verify-pch 718 719Load and verify that a pre-compiled header file is not stale 720 721Compilation flags 722================= 723 724Flags controlling the behavior of Clang during compilation. These flags have 725no effect during actions that do not perform compilation. 726 727.. option:: -Xassembler <arg> 728 729Pass <arg> to the assembler 730 731.. option:: -Xclang <arg> 732 733Pass <arg> to the clang compiler 734 735.. option:: -fclang-abi-compat=<version> 736 737Attempt to match the ABI of Clang <version> 738 739.. option:: -fcomment-block-commands=<arg>,<arg2>... 740 741Treat each comma separated argument in <arg> as a documentation comment block command 742 743.. option:: -fcomplete-member-pointers, -fno-complete-member-pointers 744 745Require member pointer base types to be complete if they would be significant under the Microsoft ABI 746 747.. option:: -fcrash-diagnostics-dir=<arg> 748 749.. option:: -fdeclspec, -fno-declspec 750 751Allow \_\_declspec as a keyword 752 753.. option:: -fdepfile-entry=<arg> 754 755.. option:: -fdiagnostics-fixit-info, -fno-diagnostics-fixit-info 756 757.. option:: -fdiagnostics-format=<arg> 758 759.. option:: -fdiagnostics-parseable-fixits 760 761Print fix-its in machine parseable form 762 763.. option:: -fdiagnostics-print-source-range-info 764 765Print source range spans in numeric form 766 767.. option:: -fdiagnostics-show-category=<arg> 768 769.. option:: -fdiscard-value-names, -fno-discard-value-names 770 771Discard value names in LLVM IR 772 773.. option:: -fexperimental-isel, -fno-experimental-isel 774 775Enables the experimental global instruction selector 776 777.. option:: -fexperimental-new-pass-manager, -fno-experimental-new-pass-manager 778 779Enables an experimental new pass manager in LLVM. 780 781.. option:: -ffine-grained-bitfield-accesses, -fno-fine-grained-bitfield-accesses 782 783Use separate accesses for consecutive bitfield runs with legal widths and alignments. 784 785.. option:: -finline-functions, -fno-inline-functions 786 787Inline suitable functions 788 789.. option:: -finline-hint-functions 790 791Inline functions which are (explicitly or implicitly) marked inline 792 793.. option:: -fno-crash-diagnostics 794 795Disable auto-generation of preprocessed source files and a script for reproduction during a clang crash 796 797.. option:: -fno-sanitize-blacklist 798 799Don't use blacklist file for sanitizers 800 801.. option:: -fparse-all-comments 802 803.. option:: -frecord-command-line, -frecord-gcc-switches, -fno-record-command-line, -fno-record-gcc-switches 804 805Generate a section named ".GCC.command.line" containing the clang driver 806command-line. After linking, the section may contain multiple command lines, 807which will be individually terminated by null bytes. Separate arguments within 808a command line are combined with spaces; spaces and backslashes within an 809argument are escaped with backslashes. This format differs from the format of 810the equivalent section produced by GCC with the -frecord-gcc-switches flag. 811This option is currently only supported on ELF targets. 812 813.. option:: -fsanitize-address-field-padding=<arg> 814 815Level of field padding for AddressSanitizer 816 817.. option:: -fsanitize-address-globals-dead-stripping 818 819Enable linker dead stripping of globals in AddressSanitizer 820 821.. option:: -fsanitize-address-use-odr-indicator, -fno-sanitize-address-use-odr-indicator 822 823Enable ODR indicator globals to avoid false ODR violation reports in partially sanitized programs at the cost of an increase in binary size 824 825.. option:: -fsanitize-address-poison-custom-array-cookie, -fno-sanitize-address-poison-custom-array-cookie 826 827Enable "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. 828 829An 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. 830 831.. option:: -fsanitize-address-use-after-scope, -fno-sanitize-address-use-after-scope 832 833Enable use-after-scope detection in AddressSanitizer 834 835.. option:: -fsanitize-blacklist=<arg> 836 837Path to blacklist file for sanitizers 838 839.. option:: -fsanitize-cfi-cross-dso, -fno-sanitize-cfi-cross-dso 840 841Enable control flow integrity (CFI) checks for cross-DSO calls. 842 843.. option:: -fsanitize-cfi-icall-generalize-pointers 844 845Generalize pointers in CFI indirect call type signature checks 846 847.. option:: -fsanitize-coverage=<arg1>,<arg2>..., -fno-sanitize-coverage=<arg1>,<arg2>... 848 849Specify the type of coverage instrumentation for Sanitizers 850 851.. option:: -fsanitize-link-c++-runtime 852 853.. option:: -fsanitize-memory-track-origins, -fno-sanitize-memory-track-origins 854 855Enable origins tracking in MemorySanitizer 856 857.. program:: clang1 858.. option:: -fsanitize-memory-track-origins=<arg> 859.. program:: clang 860 861Enable origins tracking in MemorySanitizer 862 863.. option:: -fsanitize-memory-use-after-dtor, -fno-sanitize-memory-use-after-dtor 864 865Enable use-after-destroy detection in MemorySanitizer 866 867.. option:: -fsanitize-minimal-runtime, -fno-sanitize-minimal-runtime 868 869.. option:: -fsanitize-recover, -fno-sanitize-recover 870 871.. program:: clang1 872.. option:: -fsanitize-recover=<arg1>,<arg2>..., -fno-sanitize-recover=<arg1>,<arg2>... 873.. program:: clang 874 875Enable recovery for specified sanitizers 876 877.. option:: -fsanitize-stats, -fno-sanitize-stats 878 879Enable sanitizer statistics gathering. 880 881.. option:: -fsanitize-thread-atomics, -fno-sanitize-thread-atomics 882 883Enable atomic operations instrumentation in ThreadSanitizer (default) 884 885.. option:: -fsanitize-thread-func-entry-exit, -fno-sanitize-thread-func-entry-exit 886 887Enable function entry/exit instrumentation in ThreadSanitizer (default) 888 889.. option:: -fsanitize-thread-memory-access, -fno-sanitize-thread-memory-access 890 891Enable memory access instrumentation in ThreadSanitizer (default) 892 893.. option:: -fsanitize-trap=<arg1>,<arg2>..., -fno-sanitize-trap=<arg1>,<arg2>... 894 895Enable trapping for specified sanitizers 896 897.. option:: -fsanitize-undefined-strip-path-components=<number> 898 899Strip (or keep only, if negative) a given number of path components when emitting check metadata. 900 901.. option:: -fsanitize-undefined-trap-on-error, -fno-sanitize-undefined-trap-on-error 902 903.. option:: -fsanitize=<check>,<arg2>..., -fno-sanitize=<arg1>,<arg2>... 904 905Turn on runtime checks for various forms of undefined or suspicious behavior. See user manual for available checks 906 907.. option:: -moutline, -mno-outline 908 909Enable function outlining (AArch64 only) 910 911.. option:: --param <arg>, --param=<arg> 912 913.. option:: -std=<arg>, --std=<arg>, --std <arg> 914 915Language standard to compile for 916 917Preprocessor flags 918~~~~~~~~~~~~~~~~~~ 919 920Flags controlling the behavior of the Clang preprocessor. 921 922.. option:: -C, --comments 923 924Include comments in preprocessed output 925 926.. option:: -CC, --comments-in-macros 927 928Include comments from within macros in preprocessed output 929 930.. option:: -D<macro>=<value>, --define-macro <arg>, --define-macro=<arg> 931 932Define <macro> to <value> (or 1 if <value> omitted) 933 934.. option:: -H, --trace-includes 935 936Show header includes and nesting depth 937 938.. option:: -P, --no-line-commands 939 940Disable linemarker output in -E mode 941 942.. option:: -U<macro>, --undefine-macro <arg>, --undefine-macro=<arg> 943 944Undefine macro <macro> 945 946.. option:: -Wp,<arg>,<arg2>... 947 948Pass the comma separated arguments in <arg> to the preprocessor 949 950.. option:: -Xpreprocessor <arg> 951 952Pass <arg> to the preprocessor 953 954Include path management 955----------------------- 956 957Flags controlling how ``#include``\s are resolved to files. 958 959.. option:: -I<dir>, --include-directory <arg>, --include-directory=<arg> 960 961Add directory to include search path 962 963.. option:: -I-, --include-barrier 964 965Restrict all prior -I flags to double-quoted inclusion and remove current directory from include path 966 967.. option:: --cuda-path-ignore-env 968 969Ignore environment variables to detect CUDA installation 970 971.. option:: --cuda-path=<arg> 972 973CUDA installation path 974 975.. option:: -cxx-isystem<directory> 976 977Add directory to the C++ SYSTEM include search path 978 979.. option:: -fbuild-session-file=<file> 980 981Use the last modification time of <file> as the build session timestamp 982 983.. option:: -fbuild-session-timestamp=<time since Epoch in seconds> 984 985Time when the current build session started 986 987.. option:: -fmodule-file=\[<name>=\]<file> 988 989Specify the mapping of module name to precompiled module file, or load a module file if name is omitted. 990 991.. option:: -fmodules-cache-path=<directory> 992 993Specify the module cache path 994 995.. option:: -fmodules-disable-diagnostic-validation 996 997Disable validation of the diagnostic options when loading the module 998 999.. option:: -fmodules-prune-after=<seconds> 1000 1001Specify the interval (in seconds) after which a module file will be considered unused 1002 1003.. option:: -fmodules-prune-interval=<seconds> 1004 1005Specify the interval (in seconds) between attempts to prune the module cache 1006 1007.. option:: -fmodules-user-build-path <directory> 1008 1009Specify the module user build path 1010 1011.. option:: -fmodules-validate-once-per-build-session 1012 1013Don't verify input files for the modules if the module has been successfully validated or loaded during this build session 1014 1015.. option:: -fmodules-validate-system-headers, -fno-modules-validate-system-headers 1016 1017Validate the system headers that a module depends on when loading the module 1018 1019.. option:: -fprebuilt-module-path=<directory> 1020 1021Specify the prebuilt module path 1022 1023.. option:: -idirafter<arg>, --include-directory-after <arg>, --include-directory-after=<arg> 1024 1025Add directory to AFTER include search path 1026 1027.. option:: -iframework<arg> 1028 1029Add directory to SYSTEM framework search path 1030 1031.. option:: -iframeworkwithsysroot<directory> 1032 1033Add directory to SYSTEM framework search path, absolute paths are relative to -isysroot 1034 1035.. option:: -imacros<file>, --imacros<file>, --imacros=<arg> 1036 1037Include macros from file before parsing 1038 1039.. option:: -include<file>, --include<file>, --include=<arg> 1040 1041Include file before parsing 1042 1043.. option:: -include-pch <file> 1044 1045Include precompiled header file 1046 1047.. option:: -iprefix<dir>, --include-prefix <arg>, --include-prefix=<arg> 1048 1049Set the -iwithprefix/-iwithprefixbefore prefix 1050 1051.. option:: -iquote<directory> 1052 1053Add directory to QUOTE include search path 1054 1055.. option:: -isysroot<dir> 1056 1057Set the system root directory (usually /) 1058 1059.. option:: -isystem<directory> 1060 1061Add directory to SYSTEM include search path 1062 1063.. option:: -isystem-after<directory> 1064 1065Add directory to end of the SYSTEM include search path 1066 1067.. option:: -ivfsoverlay<arg> 1068 1069Overlay the virtual filesystem described by file over the real file system 1070 1071.. option:: -iwithprefix<dir>, --include-with-prefix <arg>, --include-with-prefix-after <arg>, --include-with-prefix-after=<arg>, --include-with-prefix=<arg> 1072 1073Set directory to SYSTEM include search path with prefix 1074 1075.. option:: -iwithprefixbefore<dir>, --include-with-prefix-before <arg>, --include-with-prefix-before=<arg> 1076 1077Set directory to include search path with prefix 1078 1079.. option:: -iwithsysroot<directory> 1080 1081Add directory to SYSTEM include search path, absolute paths are relative to -isysroot 1082 1083.. option:: --ptxas-path=<arg> 1084 1085Path to ptxas (used for compiling CUDA code) 1086 1087.. option:: --system-header-prefix=<prefix>, --no-system-header-prefix=<prefix>, --system-header-prefix <arg> 1088 1089Treat all #include paths starting with <prefix> as including a system header. 1090 1091Dependency file generation 1092-------------------------- 1093 1094Flags controlling generation of a dependency file for ``make``-like build 1095systems. 1096 1097.. option:: -M, --dependencies 1098 1099Like -MD, but also implies -E and writes to stdout by default 1100 1101.. option:: -MD, --write-dependencies 1102 1103Write a depfile containing user and system headers 1104 1105.. option:: -MF<file> 1106 1107Write depfile output from -MMD, -MD, -MM, or -M to <file> 1108 1109.. option:: -MG, --print-missing-file-dependencies 1110 1111Add missing headers to depfile 1112 1113.. option:: -MJ<arg> 1114 1115Write a compilation database entry per input 1116 1117.. option:: -MM, --user-dependencies 1118 1119Like -MMD, but also implies -E and writes to stdout by default 1120 1121.. option:: -MMD, --write-user-dependencies 1122 1123Write a depfile containing user headers 1124 1125.. option:: -MP 1126 1127Create phony target for each dependency (other than main file) 1128 1129.. option:: -MQ<arg> 1130 1131Specify name of main file output to quote in depfile 1132 1133.. option:: -MT<arg> 1134 1135Specify name of main file output in depfile 1136 1137.. option:: -MV 1138 1139Use NMake/Jom format for the depfile 1140 1141Dumping preprocessor state 1142-------------------------- 1143 1144Flags allowing the state of the preprocessor to be dumped in various ways. 1145 1146.. option:: -d 1147 1148.. program:: clang1 1149.. option:: -d<arg> 1150.. program:: clang 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=<file> 1703 1704Implies -fsave-optimization-record. On Darwin platforms, this 1705 cannot be used with multiple -arch <arch> options. 1706 1707.. option:: -foptimization-record-passes=<regex> 1708 1709Only include passes which match a specified regular expression in the generated optimization record (by default, include all passes) 1710 1711.. option:: -foptimize-sibling-calls, -fno-optimize-sibling-calls 1712 1713.. option:: -foutput-class-dir=<arg>, --output-class-directory <arg>, --output-class-directory=<arg> 1714 1715.. option:: -fpack-struct, -fno-pack-struct 1716 1717.. program:: clang1 1718.. option:: -fpack-struct=<arg> 1719.. program:: clang 1720 1721Specify the default maximum struct packing alignment 1722 1723.. option:: -fpascal-strings, -fno-pascal-strings, -mpascal-strings 1724 1725Recognize and construct Pascal-style string literals 1726 1727.. option:: -fpcc-struct-return 1728 1729Override the default ABI to return all structs on the stack 1730 1731.. option:: -fpch-preprocess 1732 1733.. option:: -fpic, -fno-pic 1734 1735.. option:: -fpie, -fno-pie 1736 1737.. option:: -fplt, -fno-plt 1738 1739Use the PLT to make function calls 1740 1741.. option:: -fplugin=<dsopath> 1742 1743Load the named plugin (dynamic shared object) 1744 1745.. option:: -fpreserve-as-comments, -fno-preserve-as-comments 1746 1747.. option:: -fprofile-arcs, -fno-profile-arcs 1748 1749.. option:: -fprofile-dir=<arg> 1750 1751.. option:: -fprofile-generate, -fno-profile-generate 1752 1753Generate instrumented code to collect execution counts into default.profraw (overridden by LLVM\_PROFILE\_FILE env var) 1754 1755.. program:: clang1 1756.. option:: -fprofile-generate=<directory> 1757.. program:: clang 1758 1759Generate instrumented code to collect execution counts into <directory>/default.profraw (overridden by LLVM\_PROFILE\_FILE env var) 1760 1761.. option:: -fprofile-instr-generate, -fno-profile-instr-generate 1762 1763Generate instrumented code to collect execution counts into default.profraw file (overridden by '=' form of option or LLVM\_PROFILE\_FILE env var) 1764 1765.. program:: clang1 1766.. option:: -fprofile-instr-generate=<file> 1767.. program:: clang 1768 1769Generate instrumented code to collect execution counts into <file> (overridden by LLVM\_PROFILE\_FILE env var) 1770 1771.. option:: -fprofile-instr-use, -fno-profile-instr-use, -fprofile-use 1772 1773.. program:: clang1 1774.. option:: -fprofile-instr-use=<arg> 1775.. program:: clang 1776 1777Use instrumentation data for profile-guided optimization 1778 1779.. option:: -fprofile-sample-accurate, -fauto-profile-accurate, -fno-profile-sample-accurate 1780 1781Specifies that the sample profile is accurate. If the sample 1782 profile is accurate, callsites without profile samples are marked 1783 as cold. Otherwise, treat callsites without profile samples as if 1784 we have no profile 1785 1786.. option:: -fprofile-sample-use, -fauto-profile, -fno-profile-sample-use 1787 1788.. program:: clang1 1789.. option:: -fprofile-sample-use=<arg>, -fauto-profile=<arg> 1790.. program:: clang 1791 1792Enable sample-based profile guided optimizations 1793 1794.. program:: clang1 1795.. option:: -fprofile-use=<pathname> 1796.. program:: clang 1797 1798Use instrumentation data for profile-guided optimization. If pathname is a directory, it reads from <pathname>/default.profdata. Otherwise, it reads from file <pathname>. 1799 1800.. option:: -freciprocal-math, -fno-reciprocal-math 1801 1802Allow division operations to be reassociated 1803 1804.. option:: -freg-struct-return 1805 1806Override the default ABI to return small structs in registers 1807 1808.. option:: -fregister-global-dtors-with-atexit, -fno-register-global-dtors-with-atexit 1809 1810Use atexit or \_\_cxa\_atexit to register global destructors 1811 1812.. option:: -frelaxed-template-template-args, -fno-relaxed-template-template-args 1813 1814Enable C++17 relaxed template template argument matching 1815 1816.. option:: -freroll-loops, -fno-reroll-loops 1817 1818Turn on loop reroller 1819 1820.. option:: -fretain-comments-from-system-headers 1821 1822.. option:: -frewrite-imports, -fno-rewrite-imports 1823 1824.. option:: -frewrite-includes, -fno-rewrite-includes 1825 1826.. option:: -frewrite-map-file <arg> 1827 1828.. program:: clang1 1829.. option:: -frewrite-map-file=<arg> 1830.. program:: clang 1831 1832.. option:: -fropi, -fno-ropi 1833 1834.. option:: -frtti, -fno-rtti 1835 1836.. option:: -frwpi, -fno-rwpi 1837 1838.. option:: -fsave-optimization-record, -fno-save-optimization-record 1839 1840Generate a YAML optimization record file 1841 1842.. program:: clang1 1843.. option:: -fsave-optimization-record=<format> 1844.. program:: clang 1845 1846Generate an optimization record file in a specific format. 1847 1848.. option:: -fseh-exceptions 1849 1850Use SEH style exceptions 1851 1852.. option:: -fshort-enums, -fno-short-enums 1853 1854Allocate to an enum type only as many bytes as it needs for the declared range of possible values 1855 1856.. option:: -fshort-wchar, -fno-short-wchar 1857 1858Force wchar\_t to be a short unsigned int 1859 1860.. option:: -fshow-column, -fno-show-column 1861 1862.. option:: -fshow-overloads=<arg> 1863 1864Which overload candidates to show when overload resolution fails: best\|all; defaults to all 1865 1866.. option:: -fshow-source-location, -fno-show-source-location 1867 1868.. option:: -fsignaling-math, -fno-signaling-math 1869 1870.. option:: -fsigned-bitfields 1871 1872.. option:: -fsigned-char, -fno-signed-char, --signed-char 1873 1874.. option:: -fsigned-zeros, -fno-signed-zeros 1875 1876.. option:: -fsized-deallocation, -fno-sized-deallocation 1877 1878Enable C++14 sized global deallocation functions 1879 1880.. option:: -fsjlj-exceptions 1881 1882Use SjLj style exceptions 1883 1884.. option:: -fslp-vectorize, -fno-slp-vectorize, -ftree-slp-vectorize 1885 1886Enable the superword-level parallelism vectorization passes 1887 1888.. option:: -fspell-checking, -fno-spell-checking 1889 1890.. option:: -fspell-checking-limit=<arg> 1891 1892.. option:: -fsplit-dwarf-inlining, -fno-split-dwarf-inlining 1893 1894Provide minimal debug info in the object/executable to facilitate online symbolication/stack traces in the absence of .dwo/.dwp files when using Split DWARF 1895 1896.. option:: -fsplit-stack 1897 1898.. option:: -fstack-protector, -fno-stack-protector 1899 1900Enable stack protectors for functions potentially vulnerable to stack smashing 1901 1902.. option:: -fstack-protector-all 1903 1904Force the usage of stack protectors for all functions 1905 1906.. option:: -fstack-protector-strong 1907 1908Use a strong heuristic to apply stack protectors to functions 1909 1910.. option:: -fstack-size-section, -fno-stack-size-section 1911 1912Emit section containing metadata on function stack sizes 1913 1914.. option:: -fstandalone-debug, -fno-limit-debug-info, -fno-standalone-debug 1915 1916Emit full debug info for all types used by the program 1917 1918.. option:: -fstrict-aliasing, -fno-strict-aliasing 1919 1920.. option:: -fstrict-enums, -fno-strict-enums 1921 1922Enable optimizations based on the strict definition of an enum's value range 1923 1924.. option:: -fstrict-float-cast-overflow, -fno-strict-float-cast-overflow 1925 1926Assume that overflowing float-to-int casts are undefined (default) 1927 1928.. option:: -fstrict-overflow, -fno-strict-overflow 1929 1930.. option:: -fstrict-return, -fno-strict-return 1931 1932Always treat control flow paths that fall off the end of a non-void function as unreachable 1933 1934.. option:: -fstrict-vtable-pointers, -fno-strict-vtable-pointers 1935 1936Enable optimizations based on the strict rules for overwriting polymorphic C++ objects 1937 1938.. option:: -fstruct-path-tbaa, -fno-struct-path-tbaa 1939 1940.. option:: -ftabstop=<arg> 1941 1942.. option:: -ftemplate-backtrace-limit=<arg> 1943 1944.. option:: -ftemplate-depth-<arg> 1945 1946.. option:: -ftemplate-depth=<arg> 1947 1948.. option:: -ftest-coverage 1949 1950.. option:: -fthinlto-index=<arg> 1951 1952Perform ThinLTO importing using provided function summary index 1953 1954.. option:: -fthreadsafe-statics, -fno-threadsafe-statics 1955 1956.. option:: -ftime-report 1957 1958.. option:: -ftime-trace 1959 1960Turn on time profiler. Results can be analyzed with chrome://tracing or 1961`Speedscope App <https://www.speedscope.app>`_ for flamegraph visualization 1962 1963.. option:: -ftime-trace-granularity=<arg> 1964 1965Minimum time granularity (in microseconds) traced by time profiler 1966 1967.. option:: -ftls-model=<arg> 1968 1969.. option:: -ftrap-function=<arg> 1970 1971Issue call to specified function rather than a trap instruction 1972 1973.. option:: -ftrapping-math, -fno-trapping-math 1974 1975.. option:: -ftrapv 1976 1977Trap on integer overflow 1978 1979.. option:: -ftrapv-handler <arg> 1980 1981.. program:: clang1 1982.. option:: -ftrapv-handler=<function name> 1983.. program:: clang 1984 1985Specify the function to be called on overflow 1986 1987.. option:: -ftrigraphs, -fno-trigraphs, -trigraphs, --trigraphs 1988 1989Process trigraph sequences 1990 1991.. option:: -funique-section-names, -fno-unique-section-names 1992 1993Use unique names for text and data sections (ELF Only) 1994 1995.. option:: -funit-at-a-time, -fno-unit-at-a-time 1996 1997.. option:: -funroll-loops, -fno-unroll-loops 1998 1999Turn on loop unroller 2000 2001.. option:: -funsafe-math-optimizations, -fno-unsafe-math-optimizations 2002 2003.. option:: -funsigned-bitfields 2004 2005.. option:: -funsigned-char, -fno-unsigned-char, --unsigned-char 2006 2007.. option:: -funwind-tables, -fno-unwind-tables 2008 2009.. option:: -fuse-cxa-atexit, -fno-use-cxa-atexit 2010 2011.. option:: -fuse-init-array, -fno-use-init-array 2012 2013Use .init\_array instead of .ctors 2014 2015.. option:: -fuse-ld=<arg> 2016 2017.. option:: -fuse-line-directives, -fno-use-line-directives 2018 2019.. option:: -fveclib=<arg> 2020 2021Use the given vector functions library 2022 2023.. option:: -fvectorize, -fno-vectorize, -ftree-vectorize 2024 2025Enable the loop vectorization passes 2026 2027.. option:: -fverbose-asm, -fno-verbose-asm, -dA 2028 2029.. option:: -fvisibility-inlines-hidden 2030 2031Give inline C++ member functions hidden visibility by default 2032 2033.. option:: -fvisibility-ms-compat 2034 2035Give global types 'default' visibility and global functions and variables 'hidden' visibility by default 2036 2037.. option:: -fvisibility=<arg> 2038 2039Set the default symbol visibility for all global declarations 2040 2041.. option:: -fwhole-program-vtables, -fno-whole-program-vtables 2042 2043Enables whole-program vtable optimization. Requires -flto 2044 2045.. option:: -fwrapv, -fno-wrapv 2046 2047Treat signed integer overflow as two's complement 2048 2049.. option:: -fwritable-strings 2050 2051Store string literals as writable data 2052 2053.. option:: -fxray-always-emit-customevents, -fno-xray-always-emit-customevents 2054 2055Determine whether to always emit \_\_xray\_customevent(...) calls even if the function it appears in is not always instrumented. 2056 2057.. option:: -fxray-always-emit-typedevents, -fno-xray-always-emit-typedevents 2058 2059Determine whether to always emit \_\_xray\_typedevent(...) calls even if the function it appears in is not always instrumented. 2060 2061.. option:: -fxray-always-instrument=<arg> 2062 2063DEPRECATED: Filename defining the whitelist for imbuing the 'always instrument' XRay attribute. 2064 2065.. option:: -fxray-attr-list=<arg> 2066 2067Filename defining the list of functions/types for imbuing XRay attributes. 2068 2069.. option:: -fxray-instruction-threshold<arg> 2070 2071.. program:: clang1 2072.. option:: -fxray-instruction-threshold=<arg> 2073.. program:: clang 2074 2075Sets the minimum function size to instrument with XRay 2076 2077.. option:: -fxray-instrument, -fno-xray-instrument 2078 2079Generate XRay instrumentation sleds on function entry and exit 2080 2081.. option:: -fxray-instrumentation-bundle=<arg> 2082 2083Select which XRay instrumentation points to emit. Options: all, none, function, custom. Default is 'all'. 2084 2085.. option:: -fxray-link-deps 2086 2087Tells clang to add the link dependencies for XRay. 2088 2089.. option:: -fxray-modes=<arg> 2090 2091List of modes to link in by default into XRay instrumented binaries. 2092 2093.. option:: -fxray-never-instrument=<arg> 2094 2095DEPRECATED: Filename defining the whitelist for imbuing the 'never instrument' XRay attribute. 2096 2097.. option:: -fzero-initialized-in-bss, -fno-zero-initialized-in-bss 2098 2099.. option:: -fzvector, -fno-zvector, -mzvector 2100 2101Enable System z vector language extension 2102 2103.. option:: -pedantic, --pedantic, -no-pedantic, --no-pedantic 2104 2105.. option:: -pedantic-errors, --pedantic-errors 2106 2107OpenCL flags 2108------------ 2109.. option:: -cl-denorms-are-zero 2110 2111OpenCL only. Allow denormals to be flushed to zero. 2112 2113.. option:: -cl-fast-relaxed-math 2114 2115OpenCL only. Sets -cl-finite-math-only and -cl-unsafe-math-optimizations, and defines \_\_FAST\_RELAXED\_MATH\_\_. 2116 2117.. option:: -cl-finite-math-only 2118 2119OpenCL only. Allow floating-point optimizations that assume arguments and results are not NaNs or +-Inf. 2120 2121.. option:: -cl-fp32-correctly-rounded-divide-sqrt 2122 2123OpenCL only. Specify that single precision floating-point divide and sqrt used in the program source are correctly rounded. 2124 2125.. option:: -cl-kernel-arg-info 2126 2127OpenCL only. Generate kernel argument metadata. 2128 2129.. option:: -cl-mad-enable 2130 2131OpenCL only. Allow use of less precise MAD computations in the generated binary. 2132 2133.. option:: -cl-no-signed-zeros 2134 2135OpenCL only. Allow use of less precise no signed zeros computations in the generated binary. 2136 2137.. option:: -cl-opt-disable 2138 2139OpenCL only. This option disables all optimizations. By default optimizations are enabled. 2140 2141.. option:: -cl-single-precision-constant 2142 2143OpenCL only. Treat double precision floating-point constant as single precision constant. 2144 2145.. option:: -cl-std=<arg> 2146 2147OpenCL language standard to compile for. 2148 2149.. option:: -cl-strict-aliasing 2150 2151OpenCL only. This option is added for compatibility with OpenCL 1.0. 2152 2153.. option:: -cl-uniform-work-group-size 2154 2155OpenCL only. Defines that the global work-size be a multiple of the work-group size specified to clEnqueueNDRangeKernel 2156 2157.. option:: -cl-unsafe-math-optimizations 2158 2159OpenCL only. Allow unsafe floating-point optimizations. Also implies -cl-no-signed-zeros and -cl-mad-enable. 2160 2161Target-dependent compilation options 2162~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 2163.. option:: -G<size>, -G=<arg>, -msmall-data-threshold=<arg> 2164 2165Put objects of at most <size> bytes into small data section (MIPS / Hexagon) 2166 2167.. option:: -m16 2168 2169.. option:: -m32 2170 2171.. option:: -m64 2172 2173.. option:: -mabi=<arg> 2174 2175.. option:: -malign-double 2176 2177Align doubles to two words in structs (x86 only) 2178 2179.. option:: -march=<arg> 2180 2181.. option:: -masm=<arg> 2182 2183.. option:: -mbackchain, -mno-backchain 2184 2185Link stack frames through backchain on System Z 2186 2187.. option:: -mcmodel=<arg> 2188 2189.. option:: -mconsole<arg> 2190 2191.. 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) 2192 2193Use -mcpu=? to see a list of supported cpu models. 2194 2195.. option:: -mcrc, -mno-crc 2196 2197Allow use of CRC instructions (ARM/Mips only) 2198 2199.. option:: -mdefault-build-attributes<arg>, -mno-default-build-attributes<arg> 2200 2201.. option:: -mdll<arg> 2202 2203.. option:: -mdynamic-no-pic<arg> 2204 2205.. option:: -meabi <arg> 2206 2207Set EABI type, e.g. 4, 5 or gnu (default depends on triple) 2208 2209.. option:: -mfentry 2210 2211Insert calls to fentry at function entry (x86/SystemZ only) 2212 2213.. option:: -mfloat-abi=<arg> 2214 2215.. option:: -mfpmath=<arg> 2216 2217.. option:: -mfpu=<arg> 2218 2219.. option:: -mglobal-merge, -mno-global-merge 2220 2221Enable merging of globals 2222 2223.. option:: -mhard-float 2224 2225.. option:: -mhwdiv=<arg>, --mhwdiv <arg>, --mhwdiv=<arg> 2226 2227.. option:: -miamcu, -mno-iamcu 2228 2229Use Intel MCU ABI 2230 2231.. option:: -mimplicit-float, -mno-implicit-float 2232 2233.. option:: -mimplicit-it=<arg> 2234 2235.. option:: -mincremental-linker-compatible, -mno-incremental-linker-compatible 2236 2237(integrated-as) Emit an object file which can be used with an incremental linker 2238 2239.. option:: -miphoneos-version-min=<arg>, -mios-version-min=<arg> 2240 2241.. option:: -mkernel 2242 2243.. option:: -mlong-calls, -mno-long-calls 2244 2245Generate branches with extended addressability, usually via indirect jumps. 2246 2247.. option:: -mmacosx-version-min=<arg>, -mmacos-version-min=<arg> 2248 2249Set macOS deployment target 2250 2251.. option:: -mmcu=<arg> 2252 2253.. option:: -mms-bitfields, -mno-ms-bitfields 2254 2255Set the default structure layout to be compatible with the Microsoft compiler standard 2256 2257.. option:: -momit-leaf-frame-pointer, -mno-omit-leaf-frame-pointer 2258 2259Omit frame pointer setup for leaf functions 2260 2261.. option:: -moslib=<arg> 2262 2263.. option:: -mpie-copy-relocations, -mno-pie-copy-relocations 2264 2265Use copy relocations support for PIE builds 2266 2267.. option:: -mprefer-vector-width=<arg> 2268 2269Specifies preferred vector width for auto-vectorization. Defaults to 'none' which allows target specific decisions. 2270 2271.. option:: -mqdsp6-compat 2272 2273Enable hexagon-qdsp6 backward compatibility 2274 2275.. option:: -mrecip 2276 2277.. program:: clang1 2278.. option:: -mrecip=<arg1>,<arg2>... 2279.. program:: clang 2280 2281.. option:: -mred-zone, -mno-red-zone 2282 2283.. option:: -mregparm=<arg> 2284 2285.. option:: -mrelax-all, -mno-relax-all 2286 2287(integrated-as) Relax all machine instructions 2288 2289.. option:: -mretpoline, -mno-retpoline 2290 2291.. option:: -mrtd, -mno-rtd 2292 2293Make StdCall calling convention the default 2294 2295.. option:: -msign-return-address=<arg> 2296 2297Select return address signing scope 2298 2299.. option:: -msoft-float, -mno-soft-float 2300 2301Use software floating point 2302 2303.. option:: -mstack-alignment=<arg> 2304 2305Set the stack alignment 2306 2307.. option:: -mstack-arg-probe, -mno-stack-arg-probe 2308 2309Enable stack probes 2310 2311.. option:: -mstack-probe-size=<arg> 2312 2313Set the stack probe size 2314 2315.. option:: -mstackrealign, -mno-stackrealign 2316 2317Force realign the stack at entry to every function 2318 2319.. option:: -mthread-model <arg> 2320 2321The thread model to use, e.g. posix, single (posix by default) 2322 2323.. option:: -mthreads<arg> 2324 2325.. option:: -mthumb, -mno-thumb 2326 2327.. option:: -mtune=<arg> 2328 2329Use -mtune=? to see a list of supported cpu models. 2330 2331.. option:: -mtvos-version-min=<arg>, -mappletvos-version-min=<arg> 2332 2333.. option:: -municode<arg> 2334 2335.. option:: -mvx, -mno-vx 2336 2337.. option:: -mwarn-nonportable-cfstrings, -mno-warn-nonportable-cfstrings 2338 2339.. option:: -mwatchos-version-min=<arg> 2340 2341.. option:: -mwindows<arg> 2342 2343.. option:: -mx32 2344 2345AARCH64 2346------- 2347.. option:: -ffixed-x1 2348 2349Reserve the x1 register (AArch64 only) 2350 2351.. option:: -ffixed-x2 2352 2353Reserve the x2 register (AArch64 only) 2354 2355.. option:: -ffixed-x3 2356 2357Reserve the x3 register (AArch64 only) 2358 2359.. option:: -ffixed-x4 2360 2361Reserve the x4 register (AArch64 only) 2362 2363.. option:: -ffixed-x5 2364 2365Reserve the x5 register (AArch64 only) 2366 2367.. option:: -ffixed-x6 2368 2369Reserve the x6 register (AArch64 only) 2370 2371.. option:: -ffixed-x7 2372 2373Reserve the x7 register (AArch64 only) 2374 2375.. option:: -ffixed-x18 2376 2377Reserve the x18 register (AArch64 only) 2378 2379.. option:: -ffixed-x20 2380 2381Reserve the x20 register (AArch64 only) 2382 2383.. option:: -fcall-saved-x8 2384 2385Make the x8 register call-saved (AArch64 only) 2386 2387.. option:: -fcall-saved-x9 2388 2389Make the x9 register call-saved (AArch64 only) 2390 2391.. option:: -fcall-saved-x10 2392 2393Make the x10 register call-saved (AArch64 only) 2394 2395.. option:: -fcall-saved-x11 2396 2397Make the x11 register call-saved (AArch64 only) 2398 2399.. option:: -fcall-saved-x12 2400 2401Make the x12 register call-saved (AArch64 only) 2402 2403.. option:: -fcall-saved-x13 2404 2405Make the x13 register call-saved (AArch64 only) 2406 2407.. option:: -fcall-saved-x14 2408 2409Make the x14 register call-saved (AArch64 only) 2410 2411.. option:: -fcall-saved-x15 2412 2413Make the x15 register call-saved (AArch64 only) 2414 2415.. option:: -fcall-saved-x18 2416 2417Make the x18 register call-saved (AArch64 only) 2418 2419.. option:: -mfix-cortex-a53-835769, -mno-fix-cortex-a53-835769 2420 2421Workaround Cortex-A53 erratum 835769 (AArch64 only) 2422 2423.. option:: -mgeneral-regs-only 2424 2425Generate code which only uses the general purpose registers (AArch64 only) 2426 2427AMDGPU 2428------ 2429.. option:: -mcumode, -mno-cumode 2430 2431CU wavefront execution mode is used if enabled and WGP wavefront execution mode 2432is used if disabled (AMDGPU only) 2433 2434.. option:: -mwavefrontsize64, -mno-wavefrontsize64 2435 2436Wavefront size 64 is used if enabled and wavefront size 32 if disabled (AMDGPU only) 2437 2438.. option:: -mxnack, -mno-xnack 2439 2440Enable XNACK (AMDGPU only) 2441 2442ARM 2443--- 2444.. option:: -ffixed-r9 2445 2446Reserve the r9 register (ARM only) 2447 2448.. option:: -mexecute-only, -mno-execute-only, -mpure-code 2449 2450Disallow generation of data access to code sections (ARM only) 2451 2452.. option:: -mno-movt 2453 2454Disallow use of movt/movw pairs (ARM only) 2455 2456.. option:: -mno-neg-immediates 2457 2458Disallow converting instructions with negative immediates to their negation or inversion. 2459 2460.. option:: -mnocrc 2461 2462Disallow use of CRC instructions (ARM only) 2463 2464.. option:: -mrestrict-it, -mno-restrict-it 2465 2466Disallow generation of deprecated IT blocks for ARMv8. It is on by default for ARMv8 Thumb mode. 2467 2468.. option:: -mtp=<arg> 2469 2470Read thread pointer from coprocessor register (ARM only) 2471 2472.. option:: -munaligned-access, -mno-unaligned-access 2473 2474Allow memory accesses to be unaligned (AArch32/AArch64 only) 2475 2476Hexagon 2477------- 2478.. option:: -mieee-rnd-near 2479 2480.. option:: -mmemops, -mno-memops 2481 2482Enable generation of memop instructions 2483 2484.. option:: -mnvj, -mno-nvj 2485 2486Enable generation of new-value jumps 2487 2488.. option:: -mnvs, -mno-nvs 2489 2490Enable generation of new-value stores 2491 2492.. option:: -mpackets, -mno-packets 2493 2494Enable generation of instruction packets 2495 2496Hexagon 2497------- 2498.. option:: -mhvx, -mno-hvx 2499 2500Enable Hexagon Vector eXtensions 2501 2502.. option:: -mhvx-length=<arg> 2503 2504Set Hexagon Vector Length 2505 2506.. program:: clang1 2507.. option:: -mhvx=<arg> 2508.. program:: clang 2509 2510Enable Hexagon Vector eXtensions 2511 2512MIPS 2513---- 2514.. option:: -mabicalls, -mno-abicalls 2515 2516Enable SVR4-style position-independent code (Mips only) 2517 2518.. option:: -mabs=<arg> 2519 2520.. option:: -mcheck-zero-division, -mno-check-zero-division 2521 2522.. option:: -mcompact-branches=<arg> 2523 2524.. option:: -mdouble-float 2525 2526.. option:: -mdsp, -mno-dsp 2527 2528.. option:: -mdspr2, -mno-dspr2 2529 2530.. option:: -membedded-data, -mno-embedded-data 2531 2532Place constants in the .rodata section instead of the .sdata section even if they meet the -G <size> threshold (MIPS) 2533 2534.. option:: -mextern-sdata, -mno-extern-sdata 2535 2536Assume that externally defined data is in the small data if it meets the -G <size> threshold (MIPS) 2537 2538.. option:: -mfp32 2539 2540Use 32-bit floating point registers (MIPS only) 2541 2542.. option:: -mfp64 2543 2544Use 64-bit floating point registers (MIPS only) 2545 2546.. option:: -mginv, -mno-ginv 2547 2548.. option:: -mgpopt, -mno-gpopt 2549 2550Use GP relative accesses for symbols known to be in a small data section (MIPS) 2551 2552.. option:: -mindirect-jump=<arg> 2553 2554Change indirect jump instructions to inhibit speculation 2555 2556.. option:: -mips16 2557 2558.. option:: -mldc1-sdc1, -mno-ldc1-sdc1 2559 2560.. option:: -mlocal-sdata, -mno-local-sdata 2561 2562Extend the -G behaviour to object local data (MIPS) 2563 2564.. option:: -mmadd4, -mno-madd4 2565 2566Enable the generation of 4-operand madd.s, madd.d and related instructions. 2567 2568.. option:: -mmicromips, -mno-micromips 2569 2570.. option:: -mmsa, -mno-msa 2571 2572Enable MSA ASE (MIPS only) 2573 2574.. option:: -mmt, -mno-mt 2575 2576Enable MT ASE (MIPS only) 2577 2578.. option:: -mnan=<arg> 2579 2580.. option:: -mno-mips16 2581 2582.. option:: -msingle-float 2583 2584.. option:: -mvirt, -mno-virt 2585 2586.. option:: -mxgot, -mno-xgot 2587 2588PowerPC 2589------- 2590.. option:: -maltivec, -mno-altivec 2591 2592.. option:: -mcmpb, -mno-cmpb 2593 2594.. option:: -mcrbits, -mno-crbits 2595 2596.. option:: -mcrypto, -mno-crypto 2597 2598.. option:: -mdirect-move, -mno-direct-move 2599 2600.. option:: -mfloat128, -mno-float128 2601 2602.. option:: -mfprnd, -mno-fprnd 2603 2604.. option:: -mhtm, -mno-htm 2605 2606.. option:: -minvariant-function-descriptors, -mno-invariant-function-descriptors 2607 2608.. option:: -misel, -mno-isel 2609 2610.. option:: -mlongcall, -mno-longcall 2611 2612.. option:: -mmfocrf, -mmfcrf, -mno-mfocrf 2613 2614.. option:: -mpopcntd, -mno-popcntd 2615 2616.. option:: -mpower8-vector, -mno-power8-vector 2617 2618.. option:: -mpower9-vector, -mno-power9-vector 2619 2620.. option:: -mqpx, -mno-qpx 2621 2622.. option:: -msecure-plt 2623 2624.. option:: -mvsx, -mno-vsx 2625 2626WebAssembly 2627----------- 2628.. option:: -mexception-handling, -mno-exception-handling 2629 2630.. option:: -mnontrapping-fptoint, -mno-nontrapping-fptoint 2631 2632.. option:: -msign-ext, -mno-sign-ext 2633 2634.. option:: -msimd128, -mno-simd128 2635 2636X86 2637--- 2638.. option:: -m3dnow, -mno-3dnow 2639 2640.. option:: -m3dnowa, -mno-3dnowa 2641 2642.. option:: -madx, -mno-adx 2643 2644.. option:: -maes, -mno-aes 2645 2646.. option:: -mavx, -mno-avx 2647 2648.. option:: -mavx2, -mno-avx2 2649 2650.. option:: -mavx512bitalg, -mno-avx512bitalg 2651 2652.. option:: -mavx512bf16, -mno-avx512bf16 2653 2654.. option:: -mavx512bw, -mno-avx512bw 2655 2656.. option:: -mavx512cd, -mno-avx512cd 2657 2658.. option:: -mavx512dq, -mno-avx512dq 2659 2660.. option:: -mavx512er, -mno-avx512er 2661 2662.. option:: -mavx512f, -mno-avx512f 2663 2664.. option:: -mavx512ifma, -mno-avx512ifma 2665 2666.. option:: -mavx512pf, -mno-avx512pf 2667 2668.. option:: -mavx512vbmi, -mno-avx512vbmi 2669 2670.. option:: -mavx512vbmi2, -mno-avx512vbmi2 2671 2672.. option:: -mavx512vl, -mno-avx512vl 2673 2674.. option:: -mavx512vnni, -mno-avx512vnni 2675 2676.. option:: -mavx512vp2intersect, -mno-avx512vp2intersect 2677 2678.. option:: -mavx512vpopcntdq, -mno-avx512vpopcntdq 2679 2680.. option:: -mbmi, -mno-bmi 2681 2682.. option:: -mbmi2, -mno-bmi2 2683 2684.. option:: -mcldemote, -mno-cldemote 2685 2686.. option:: -mclflushopt, -mno-clflushopt 2687 2688.. option:: -mclwb, -mno-clwb 2689 2690.. option:: -mclzero, -mno-clzero 2691 2692.. option:: -mcx16, -mno-cx16 2693 2694.. option:: -menqcmd, -mno-enqcmd 2695 2696.. option:: -mf16c, -mno-f16c 2697 2698.. option:: -mfma, -mno-fma 2699 2700.. option:: -mfma4, -mno-fma4 2701 2702.. option:: -mfsgsbase, -mno-fsgsbase 2703 2704.. option:: -mfxsr, -mno-fxsr 2705 2706.. option:: -mgfni, -mno-gfni 2707 2708.. option:: -minvpcid, -mno-invpcid 2709 2710.. option:: -mlwp, -mno-lwp 2711 2712.. option:: -mlzcnt, -mno-lzcnt 2713 2714.. option:: -mmmx, -mno-mmx 2715 2716.. option:: -mmovbe, -mno-movbe 2717 2718.. option:: -mmovdir64b, -mno-movdir64b 2719 2720.. option:: -mmovdiri, -mno-movdiri 2721 2722.. option:: -mmpx, -mno-mpx 2723 2724.. option:: -mmwaitx, -mno-mwaitx 2725 2726.. option:: -mpclmul, -mno-pclmul 2727 2728.. option:: -mpconfig, -mno-pconfig 2729 2730.. option:: -mpku, -mno-pku 2731 2732.. option:: -mpopcnt, -mno-popcnt 2733 2734.. option:: -mprefetchwt1, -mno-prefetchwt1 2735 2736.. option:: -mprfchw, -mno-prfchw 2737 2738.. option:: -mptwrite, -mno-ptwrite 2739 2740.. option:: -mrdpid, -mno-rdpid 2741 2742.. option:: -mrdrnd, -mno-rdrnd 2743 2744.. option:: -mrdseed, -mno-rdseed 2745 2746.. option:: -mretpoline-external-thunk, -mno-retpoline-external-thunk 2747 2748.. option:: -mrtm, -mno-rtm 2749 2750.. option:: -msahf, -mno-sahf 2751 2752.. option:: -msgx, -mno-sgx 2753 2754.. option:: -msha, -mno-sha 2755 2756.. option:: -mshstk, -mno-shstk 2757 2758.. option:: -msse, -mno-sse 2759 2760.. option:: -msse2, -mno-sse2 2761 2762.. option:: -msse3, -mno-sse3 2763 2764.. option:: -msse4.1, -mno-sse4.1 2765 2766.. program:: clang1 2767.. option:: -msse4.2, -mno-sse4.2, -msse4 2768.. program:: clang 2769 2770.. option:: -msse4a, -mno-sse4a 2771 2772.. option:: -mssse3, -mno-ssse3 2773 2774.. option:: -mtbm, -mno-tbm 2775 2776.. option:: -mvaes, -mno-vaes 2777 2778.. option:: -mvpclmulqdq, -mno-vpclmulqdq 2779 2780.. option:: -mwaitpkg, -mno-waitpkg 2781 2782.. option:: -mwbnoinvd, -mno-wbnoinvd 2783 2784.. option:: -mx87, -m80387, -mno-x87 2785 2786.. option:: -mxop, -mno-xop 2787 2788.. option:: -mxsave, -mno-xsave 2789 2790.. option:: -mxsavec, -mno-xsavec 2791 2792.. option:: -mxsaveopt, -mno-xsaveopt 2793 2794.. option:: -mxsaves, -mno-xsaves 2795 2796RISCV 2797----- 2798.. option:: -mrelax, -mno-relax 2799 2800Enable linker relaxation 2801 2802Optimization level 2803~~~~~~~~~~~~~~~~~~ 2804 2805Flags controlling how much optimization should be performed. 2806 2807.. option:: -O<arg>, -O (equivalent to -O2), --optimize, --optimize=<arg> 2808 2809.. option:: -Ofast<arg> 2810 2811Debug information generation 2812~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 2813 2814Flags controlling how much and what kind of debug information should be 2815generated. 2816 2817Kind and level of debug information 2818----------------------------------- 2819.. option:: -g, --debug, --debug=<arg> 2820 2821Generate source-level debug information 2822 2823.. option:: -gdwarf-2 2824 2825Generate source-level debug information with dwarf version 2 2826 2827.. option:: -gdwarf-3 2828 2829Generate source-level debug information with dwarf version 3 2830 2831.. option:: -gdwarf-4, -gdwarf 2832 2833Generate source-level debug information with dwarf version 4 2834 2835.. option:: -gdwarf-5 2836 2837Generate source-level debug information with dwarf version 5 2838 2839.. option:: -gfull 2840 2841.. option:: -gused 2842 2843Debug level 2844___________ 2845.. option:: -g0 2846 2847.. option:: -g2 2848 2849.. option:: -g3 2850 2851.. option:: -ggdb0 2852 2853.. option:: -ggdb1 2854 2855.. option:: -ggdb2 2856 2857.. option:: -ggdb3 2858 2859.. option:: -gline-tables-only, -g1, -gmlt 2860 2861Emit debug line number tables only 2862 2863.. option:: -gmodules 2864 2865Generate debug info with external references to clang modules or precompiled headers 2866 2867Debugger to tune debug information for 2868______________________________________ 2869.. option:: -ggdb 2870 2871.. option:: -glldb 2872 2873.. option:: -gsce 2874 2875Debug information flags 2876----------------------- 2877.. option:: -gcolumn-info, -gno-column-info 2878 2879.. option:: -gdwarf-aranges 2880 2881.. option:: -gembed-source, -gno-embed-source 2882 2883Embed source text in DWARF debug sections 2884 2885.. option:: -ggnu-pubnames, -gno-gnu-pubnames 2886 2887.. option:: -gpubnames, -gno-pubnames 2888 2889.. option:: -grecord-command-line, -grecord-gcc-switches, -gno-record-command-line, -gno-record-gcc-switches 2890 2891.. option:: -gsplit-dwarf 2892 2893.. option:: -gstrict-dwarf, -gno-strict-dwarf 2894 2895.. option:: -gz 2896 2897DWARF debug sections compression type 2898 2899.. program:: clang1 2900.. option:: -gz=<arg> 2901.. program:: clang 2902 2903DWARF debug sections compression type 2904 2905Static analyzer flags 2906===================== 2907 2908Flags controlling the behavior of the Clang Static Analyzer. 2909 2910.. option:: -Xanalyzer <arg> 2911 2912Pass <arg> to the static analyzer 2913 2914Fortran compilation flags 2915========================= 2916 2917Flags that will be passed onto the ``gfortran`` compiler when Clang is given 2918a Fortran input. 2919 2920.. option:: -A<arg>, --assert <arg>, --assert=<arg> 2921 2922.. option:: -A-<arg> 2923 2924.. option:: -J<arg> 2925 2926.. option:: -cpp 2927 2928.. option:: -faggressive-function-elimination, -fno-aggressive-function-elimination 2929 2930.. option:: -falign-commons, -fno-align-commons 2931 2932.. option:: -fall-intrinsics, -fno-all-intrinsics 2933 2934.. option:: -fautomatic, -fno-automatic 2935 2936.. option:: -fbackslash, -fno-backslash 2937 2938.. option:: -fbacktrace, -fno-backtrace 2939 2940.. option:: -fblas-matmul-limit=<arg> 2941 2942.. option:: -fbounds-check, -fno-bounds-check 2943 2944.. option:: -fcheck-array-temporaries, -fno-check-array-temporaries 2945 2946.. option:: -fcheck=<arg> 2947 2948.. option:: -fcoarray=<arg> 2949 2950.. option:: -fconvert=<arg> 2951 2952.. option:: -fcray-pointer, -fno-cray-pointer 2953 2954.. option:: -fd-lines-as-code, -fno-d-lines-as-code 2955 2956.. option:: -fd-lines-as-comments, -fno-d-lines-as-comments 2957 2958.. option:: -fdefault-double-8, -fno-default-double-8 2959 2960.. option:: -fdefault-integer-8, -fno-default-integer-8 2961 2962.. option:: -fdefault-real-8, -fno-default-real-8 2963 2964.. option:: -fdollar-ok, -fno-dollar-ok 2965 2966.. option:: -fdump-fortran-optimized, -fno-dump-fortran-optimized 2967 2968.. option:: -fdump-fortran-original, -fno-dump-fortran-original 2969 2970.. option:: -fdump-parse-tree, -fno-dump-parse-tree 2971 2972.. option:: -fexternal-blas, -fno-external-blas 2973 2974.. option:: -ff2c, -fno-f2c 2975 2976.. option:: -ffixed-form, -fno-fixed-form 2977 2978.. option:: -ffixed-line-length-<arg> 2979 2980.. option:: -ffpe-trap=<arg> 2981 2982.. option:: -ffree-form, -fno-free-form 2983 2984.. option:: -ffree-line-length-<arg> 2985 2986.. option:: -ffrontend-optimize, -fno-frontend-optimize 2987 2988.. option:: -fimplicit-none, -fno-implicit-none 2989 2990.. option:: -finit-character=<arg> 2991 2992.. option:: -finit-integer=<arg> 2993 2994.. option:: -finit-local-zero, -fno-init-local-zero 2995 2996.. option:: -finit-logical=<arg> 2997 2998.. option:: -finit-real=<arg> 2999 3000.. option:: -finteger-4-integer-8, -fno-integer-4-integer-8 3001 3002.. option:: -fintrinsic-modules-path, -fno-intrinsic-modules-path 3003 3004.. option:: -fmax-array-constructor=<arg> 3005 3006.. option:: -fmax-errors=<arg> 3007 3008.. option:: -fmax-identifier-length, -fno-max-identifier-length 3009 3010.. option:: -fmax-stack-var-size=<arg> 3011 3012.. option:: -fmax-subrecord-length=<arg> 3013 3014.. option:: -fmodule-private, -fno-module-private 3015 3016.. option:: -fpack-derived, -fno-pack-derived 3017 3018.. option:: -fprotect-parens, -fno-protect-parens 3019 3020.. option:: -frange-check, -fno-range-check 3021 3022.. option:: -freal-4-real-10, -fno-real-4-real-10 3023 3024.. option:: -freal-4-real-16, -fno-real-4-real-16 3025 3026.. option:: -freal-4-real-8, -fno-real-4-real-8 3027 3028.. option:: -freal-8-real-10, -fno-real-8-real-10 3029 3030.. option:: -freal-8-real-16, -fno-real-8-real-16 3031 3032.. option:: -freal-8-real-4, -fno-real-8-real-4 3033 3034.. option:: -frealloc-lhs, -fno-realloc-lhs 3035 3036.. option:: -frecord-marker=<arg> 3037 3038.. option:: -frecursive, -fno-recursive 3039 3040.. option:: -frepack-arrays, -fno-repack-arrays 3041 3042.. option:: -fsecond-underscore, -fno-second-underscore 3043 3044.. option:: -fsign-zero, -fno-sign-zero 3045 3046.. option:: -fstack-arrays, -fno-stack-arrays 3047 3048.. option:: -funderscoring, -fno-underscoring 3049 3050.. option:: -fwhole-file, -fno-whole-file 3051 3052.. option:: -imultilib <arg> 3053 3054.. option:: -nocpp 3055 3056.. option:: -static-libgfortran 3057 3058Linker flags 3059============ 3060Flags that are passed on to the linker 3061 3062.. option:: -L<dir>, --library-directory <arg>, --library-directory=<arg> 3063 3064Add directory to library search path 3065 3066.. option:: -Mach 3067 3068.. option:: -T<script> 3069 3070Specify <script> as linker script 3071 3072.. option:: -Tbss<addr> 3073 3074Set starting address of BSS to <addr> 3075 3076.. option:: -Tdata<addr> 3077 3078Set starting address of DATA to <addr> 3079 3080.. option:: -Ttext<addr> 3081 3082Set starting address of TEXT to <addr> 3083 3084.. option:: -Wl,<arg>,<arg2>... 3085 3086Pass the comma separated arguments in <arg> to the linker 3087 3088.. option:: -X 3089 3090.. option:: -Xlinker <arg>, --for-linker <arg>, --for-linker=<arg> 3091 3092Pass <arg> to the linker 3093 3094.. program:: clang1 3095.. option:: -Z 3096.. program:: clang 3097 3098.. option:: -e<arg>, --entry 3099 3100.. option:: -filelist <arg> 3101 3102.. option:: --hip-device-lib-path=<arg> 3103 3104HIP device library path 3105 3106.. option:: --hip-device-lib=<arg> 3107 3108HIP device library 3109 3110.. option:: -l<arg> 3111 3112.. option:: -r 3113 3114.. option:: -rpath <arg> 3115 3116.. option:: -s 3117 3118.. option:: -t 3119 3120.. option:: -u<arg>, --force-link <arg>, --force-link=<arg> 3121 3122.. option:: -undef 3123 3124undef all system defines 3125 3126.. option:: -undefined<arg>, --no-undefined 3127 3128.. option:: -z <arg> 3129 3130Pass -z <arg> to the linker 3131 3132