1 //===--- WebAssembly.cpp - WebAssembly ToolChain Implementation -*- C++ -*-===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "WebAssembly.h" 10 #include "CommonArgs.h" 11 #include "Gnu.h" 12 #include "clang/Basic/Version.h" 13 #include "clang/Config/config.h" 14 #include "clang/Driver/Compilation.h" 15 #include "clang/Driver/Driver.h" 16 #include "clang/Driver/DriverDiagnostic.h" 17 #include "clang/Driver/Options.h" 18 #include "llvm/Option/ArgList.h" 19 #include "llvm/Support/FileSystem.h" 20 #include "llvm/Support/Path.h" 21 #include "llvm/Support/VirtualFileSystem.h" 22 23 using namespace clang::driver; 24 using namespace clang::driver::tools; 25 using namespace clang::driver::toolchains; 26 using namespace clang; 27 using namespace llvm::opt; 28 29 /// Following the conventions in https://wiki.debian.org/Multiarch/Tuples, 30 /// we remove the vendor field to form the multiarch triple. 31 std::string WebAssembly::getMultiarchTriple(const Driver &D, 32 const llvm::Triple &TargetTriple, 33 StringRef SysRoot) const { 34 return (TargetTriple.getArchName() + "-" + 35 TargetTriple.getOSAndEnvironmentName()).str(); 36 } 37 38 std::string wasm::Linker::getLinkerPath(const ArgList &Args) const { 39 const ToolChain &ToolChain = getToolChain(); 40 if (const Arg* A = Args.getLastArg(options::OPT_fuse_ld_EQ)) { 41 StringRef UseLinker = A->getValue(); 42 if (!UseLinker.empty()) { 43 if (llvm::sys::path::is_absolute(UseLinker) && 44 llvm::sys::fs::can_execute(UseLinker)) 45 return std::string(UseLinker); 46 47 // Accept 'lld', and 'ld' as aliases for the default linker 48 if (UseLinker != "lld" && UseLinker != "ld") 49 ToolChain.getDriver().Diag(diag::err_drv_invalid_linker_name) 50 << A->getAsString(Args); 51 } 52 } 53 54 return ToolChain.GetProgramPath(ToolChain.getDefaultLinker()); 55 } 56 57 void wasm::Linker::ConstructJob(Compilation &C, const JobAction &JA, 58 const InputInfo &Output, 59 const InputInfoList &Inputs, 60 const ArgList &Args, 61 const char *LinkingOutput) const { 62 63 const ToolChain &ToolChain = getToolChain(); 64 const char *Linker = Args.MakeArgString(getLinkerPath(Args)); 65 ArgStringList CmdArgs; 66 67 CmdArgs.push_back("-m"); 68 if (ToolChain.getTriple().isArch64Bit()) 69 CmdArgs.push_back("wasm64"); 70 else 71 CmdArgs.push_back("wasm32"); 72 73 if (Args.hasArg(options::OPT_s)) 74 CmdArgs.push_back("--strip-all"); 75 76 Args.AddAllArgs(CmdArgs, options::OPT_L); 77 Args.AddAllArgs(CmdArgs, options::OPT_u); 78 ToolChain.AddFilePathLibArgs(Args, CmdArgs); 79 80 bool IsCommand = true; 81 const char *Crt1; 82 const char *Entry = nullptr; 83 84 // When -shared is specified, use the reactor exec model unless 85 // specified otherwise. 86 if (Args.hasArg(options::OPT_shared)) 87 IsCommand = false; 88 89 if (const Arg *A = Args.getLastArg(options::OPT_mexec_model_EQ)) { 90 StringRef CM = A->getValue(); 91 if (CM == "command") { 92 IsCommand = true; 93 } else if (CM == "reactor") { 94 IsCommand = false; 95 } else { 96 ToolChain.getDriver().Diag(diag::err_drv_invalid_argument_to_option) 97 << CM << A->getOption().getName(); 98 } 99 } 100 101 if (IsCommand) { 102 // If crt1-command.o exists, it supports new-style commands, so use it. 103 // Otherwise, use the old crt1.o. This is a temporary transition measure. 104 // Once WASI libc no longer needs to support LLVM versions which lack 105 // support for new-style command, it can make crt1.o the same as 106 // crt1-command.o. And once LLVM no longer needs to support WASI libc 107 // versions before that, it can switch to using crt1-command.o. 108 Crt1 = "crt1.o"; 109 if (ToolChain.GetFilePath("crt1-command.o") != "crt1-command.o") 110 Crt1 = "crt1-command.o"; 111 } else { 112 Crt1 = "crt1-reactor.o"; 113 Entry = "_initialize"; 114 } 115 116 if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles)) 117 CmdArgs.push_back(Args.MakeArgString(ToolChain.GetFilePath(Crt1))); 118 if (Entry) { 119 CmdArgs.push_back(Args.MakeArgString("--entry")); 120 CmdArgs.push_back(Args.MakeArgString(Entry)); 121 } 122 123 if (Args.hasArg(options::OPT_shared)) 124 CmdArgs.push_back(Args.MakeArgString("-shared")); 125 126 AddLinkerInputs(ToolChain, Inputs, Args, CmdArgs, JA); 127 128 if (!Args.hasArg(options::OPT_nostdlib, options::OPT_nodefaultlibs)) { 129 if (ToolChain.ShouldLinkCXXStdlib(Args)) 130 ToolChain.AddCXXStdlibLibArgs(Args, CmdArgs); 131 132 if (Args.hasArg(options::OPT_pthread)) { 133 CmdArgs.push_back("-lpthread"); 134 CmdArgs.push_back("--shared-memory"); 135 } 136 137 CmdArgs.push_back("-lc"); 138 AddRunTimeLibs(ToolChain, ToolChain.getDriver(), CmdArgs, Args); 139 } 140 141 CmdArgs.push_back("-o"); 142 CmdArgs.push_back(Output.getFilename()); 143 144 C.addCommand(std::make_unique<Command>(JA, *this, 145 ResponseFileSupport::AtFileCurCP(), 146 Linker, CmdArgs, Inputs, Output)); 147 148 // When optimizing, if wasm-opt is available, run it. 149 if (Arg *A = Args.getLastArg(options::OPT_O_Group)) { 150 auto WasmOptPath = ToolChain.GetProgramPath("wasm-opt"); 151 if (WasmOptPath != "wasm-opt") { 152 StringRef OOpt = "s"; 153 if (A->getOption().matches(options::OPT_O4) || 154 A->getOption().matches(options::OPT_Ofast)) 155 OOpt = "4"; 156 else if (A->getOption().matches(options::OPT_O0)) 157 OOpt = "0"; 158 else if (A->getOption().matches(options::OPT_O)) 159 OOpt = A->getValue(); 160 161 if (OOpt != "0") { 162 const char *WasmOpt = Args.MakeArgString(WasmOptPath); 163 ArgStringList CmdArgs; 164 CmdArgs.push_back(Output.getFilename()); 165 CmdArgs.push_back(Args.MakeArgString(llvm::Twine("-O") + OOpt)); 166 CmdArgs.push_back("-o"); 167 CmdArgs.push_back(Output.getFilename()); 168 C.addCommand(std::make_unique<Command>( 169 JA, *this, ResponseFileSupport::AtFileCurCP(), WasmOpt, CmdArgs, 170 Inputs, Output)); 171 } 172 } 173 } 174 } 175 176 /// Given a base library directory, append path components to form the 177 /// LTO directory. 178 static std::string AppendLTOLibDir(const std::string &Dir) { 179 // The version allows the path to be keyed to the specific version of 180 // LLVM in used, as the bitcode format is not stable. 181 return Dir + "/llvm-lto/" LLVM_VERSION_STRING; 182 } 183 184 WebAssembly::WebAssembly(const Driver &D, const llvm::Triple &Triple, 185 const llvm::opt::ArgList &Args) 186 : ToolChain(D, Triple, Args) { 187 188 assert(Triple.isArch32Bit() != Triple.isArch64Bit()); 189 190 getProgramPaths().push_back(getDriver().getInstalledDir()); 191 192 auto SysRoot = getDriver().SysRoot; 193 if (getTriple().getOS() == llvm::Triple::UnknownOS) { 194 // Theoretically an "unknown" OS should mean no standard libraries, however 195 // it could also mean that a custom set of libraries is in use, so just add 196 // /lib to the search path. Disable multiarch in this case, to discourage 197 // paths containing "unknown" from acquiring meanings. 198 getFilePaths().push_back(SysRoot + "/lib"); 199 } else { 200 const std::string MultiarchTriple = 201 getMultiarchTriple(getDriver(), Triple, SysRoot); 202 if (D.isUsingLTO()) { 203 // For LTO, enable use of lto-enabled sysroot libraries too, if available. 204 // Note that the directory is keyed to the LLVM revision, as LLVM's 205 // bitcode format is not stable. 206 auto Dir = AppendLTOLibDir(SysRoot + "/lib/" + MultiarchTriple); 207 getFilePaths().push_back(Dir); 208 } 209 getFilePaths().push_back(SysRoot + "/lib/" + MultiarchTriple); 210 } 211 } 212 213 bool WebAssembly::IsMathErrnoDefault() const { return false; } 214 215 bool WebAssembly::IsObjCNonFragileABIDefault() const { return true; } 216 217 bool WebAssembly::UseObjCMixedDispatch() const { return true; } 218 219 bool WebAssembly::isPICDefault() const { return false; } 220 221 bool WebAssembly::isPIEDefault(const llvm::opt::ArgList &Args) const { 222 return false; 223 } 224 225 bool WebAssembly::isPICDefaultForced() const { return false; } 226 227 bool WebAssembly::hasBlocksRuntime() const { return false; } 228 229 // TODO: Support profiling. 230 bool WebAssembly::SupportsProfiling() const { return false; } 231 232 bool WebAssembly::HasNativeLLVMSupport() const { return true; } 233 234 void WebAssembly::addClangTargetOptions(const ArgList &DriverArgs, 235 ArgStringList &CC1Args, 236 Action::OffloadKind) const { 237 if (!DriverArgs.hasFlag(clang::driver::options::OPT_fuse_init_array, 238 options::OPT_fno_use_init_array, true)) 239 CC1Args.push_back("-fno-use-init-array"); 240 241 // '-pthread' implies atomics, bulk-memory, mutable-globals, and sign-ext 242 if (DriverArgs.hasFlag(options::OPT_pthread, options::OPT_no_pthread, 243 false)) { 244 if (DriverArgs.hasFlag(options::OPT_mno_atomics, options::OPT_matomics, 245 false)) 246 getDriver().Diag(diag::err_drv_argument_not_allowed_with) 247 << "-pthread" 248 << "-mno-atomics"; 249 if (DriverArgs.hasFlag(options::OPT_mno_bulk_memory, 250 options::OPT_mbulk_memory, false)) 251 getDriver().Diag(diag::err_drv_argument_not_allowed_with) 252 << "-pthread" 253 << "-mno-bulk-memory"; 254 if (DriverArgs.hasFlag(options::OPT_mno_mutable_globals, 255 options::OPT_mmutable_globals, false)) 256 getDriver().Diag(diag::err_drv_argument_not_allowed_with) 257 << "-pthread" 258 << "-mno-mutable-globals"; 259 if (DriverArgs.hasFlag(options::OPT_mno_sign_ext, options::OPT_msign_ext, 260 false)) 261 getDriver().Diag(diag::err_drv_argument_not_allowed_with) 262 << "-pthread" 263 << "-mno-sign-ext"; 264 CC1Args.push_back("-target-feature"); 265 CC1Args.push_back("+atomics"); 266 CC1Args.push_back("-target-feature"); 267 CC1Args.push_back("+bulk-memory"); 268 CC1Args.push_back("-target-feature"); 269 CC1Args.push_back("+mutable-globals"); 270 CC1Args.push_back("-target-feature"); 271 CC1Args.push_back("+sign-ext"); 272 } 273 274 if (!DriverArgs.hasFlag(options::OPT_mmutable_globals, 275 options::OPT_mno_mutable_globals, false)) { 276 // -fPIC implies +mutable-globals because the PIC ABI used by the linker 277 // depends on importing and exporting mutable globals. 278 llvm::Reloc::Model RelocationModel; 279 unsigned PICLevel; 280 bool IsPIE; 281 std::tie(RelocationModel, PICLevel, IsPIE) = 282 ParsePICArgs(*this, DriverArgs); 283 if (RelocationModel == llvm::Reloc::PIC_) { 284 if (DriverArgs.hasFlag(options::OPT_mno_mutable_globals, 285 options::OPT_mmutable_globals, false)) { 286 getDriver().Diag(diag::err_drv_argument_not_allowed_with) 287 << "-fPIC" 288 << "-mno-mutable-globals"; 289 } 290 CC1Args.push_back("-target-feature"); 291 CC1Args.push_back("+mutable-globals"); 292 } 293 } 294 295 if (DriverArgs.getLastArg(options::OPT_fwasm_exceptions)) { 296 // '-fwasm-exceptions' is not compatible with '-mno-exception-handling' 297 if (DriverArgs.hasFlag(options::OPT_mno_exception_handing, 298 options::OPT_mexception_handing, false)) 299 getDriver().Diag(diag::err_drv_argument_not_allowed_with) 300 << "-fwasm-exceptions" 301 << "-mno-exception-handling"; 302 // '-fwasm-exceptions' is not compatible with 303 // '-mllvm -enable-emscripten-cxx-exceptions' 304 for (const Arg *A : DriverArgs.filtered(options::OPT_mllvm)) { 305 if (StringRef(A->getValue(0)) == "-enable-emscripten-cxx-exceptions") 306 getDriver().Diag(diag::err_drv_argument_not_allowed_with) 307 << "-fwasm-exceptions" 308 << "-mllvm -enable-emscripten-cxx-exceptions"; 309 } 310 // '-fwasm-exceptions' implies exception-handling feature 311 CC1Args.push_back("-target-feature"); 312 CC1Args.push_back("+exception-handling"); 313 // Backend needs -wasm-enable-eh to enable Wasm EH 314 CC1Args.push_back("-mllvm"); 315 CC1Args.push_back("-wasm-enable-eh"); 316 } 317 318 for (const Arg *A : DriverArgs.filtered(options::OPT_mllvm)) { 319 StringRef Opt = A->getValue(0); 320 if (Opt.startswith("-emscripten-cxx-exceptions-allowed")) { 321 // '-mllvm -emscripten-cxx-exceptions-allowed' should be used with 322 // '-mllvm -enable-emscripten-cxx-exceptions' 323 bool EmEHArgExists = false; 324 for (const Arg *A : DriverArgs.filtered(options::OPT_mllvm)) { 325 if (StringRef(A->getValue(0)) == "-enable-emscripten-cxx-exceptions") { 326 EmEHArgExists = true; 327 break; 328 } 329 } 330 if (!EmEHArgExists) 331 getDriver().Diag(diag::err_drv_argument_only_allowed_with) 332 << "-mllvm -emscripten-cxx-exceptions-allowed" 333 << "-mllvm -enable-emscripten-cxx-exceptions"; 334 335 // Prevent functions specified in -emscripten-cxx-exceptions-allowed list 336 // from being inlined before reaching the wasm backend. 337 StringRef FuncNamesStr = Opt.split('=').second; 338 SmallVector<StringRef, 4> FuncNames; 339 FuncNamesStr.split(FuncNames, ','); 340 for (auto Name : FuncNames) { 341 CC1Args.push_back("-mllvm"); 342 CC1Args.push_back(DriverArgs.MakeArgString("--force-attribute=" + Name + 343 ":noinline")); 344 } 345 } 346 347 if (Opt.startswith("-wasm-enable-sjlj")) { 348 // '-mllvm -wasm-enable-sjlj' is not compatible with 349 // '-mno-exception-handling' 350 if (DriverArgs.hasFlag(options::OPT_mno_exception_handing, 351 options::OPT_mexception_handing, false)) 352 getDriver().Diag(diag::err_drv_argument_not_allowed_with) 353 << "-mllvm -wasm-enable-sjlj" 354 << "-mno-exception-handling"; 355 // '-mllvm -wasm-enable-sjlj' is not compatible with 356 // '-mllvm -enable-emscripten-cxx-exceptions' 357 // because we don't allow Emscripten EH + Wasm SjLj 358 for (const Arg *A : DriverArgs.filtered(options::OPT_mllvm)) { 359 if (StringRef(A->getValue(0)) == "-enable-emscripten-cxx-exceptions") 360 getDriver().Diag(diag::err_drv_argument_not_allowed_with) 361 << "-mllvm -wasm-enable-sjlj" 362 << "-mllvm -enable-emscripten-cxx-exceptions"; 363 } 364 // '-mllvm -wasm-enable-sjlj' is not compatible with 365 // '-mllvm -enable-emscripten-sjlj' 366 for (const Arg *A : DriverArgs.filtered(options::OPT_mllvm)) { 367 if (StringRef(A->getValue(0)) == "-enable-emscripten-sjlj") 368 getDriver().Diag(diag::err_drv_argument_not_allowed_with) 369 << "-mllvm -wasm-enable-sjlj" 370 << "-mllvm -enable-emscripten-sjlj"; 371 } 372 // '-mllvm -wasm-enable-sjlj' implies exception-handling feature 373 CC1Args.push_back("-target-feature"); 374 CC1Args.push_back("+exception-handling"); 375 // Backend needs '-exception-model=wasm' to use Wasm EH instructions 376 CC1Args.push_back("-exception-model=wasm"); 377 } 378 } 379 } 380 381 ToolChain::RuntimeLibType WebAssembly::GetDefaultRuntimeLibType() const { 382 return ToolChain::RLT_CompilerRT; 383 } 384 385 ToolChain::CXXStdlibType 386 WebAssembly::GetCXXStdlibType(const ArgList &Args) const { 387 if (Arg *A = Args.getLastArg(options::OPT_stdlib_EQ)) { 388 StringRef Value = A->getValue(); 389 if (Value == "libc++") 390 return ToolChain::CST_Libcxx; 391 else if (Value == "libstdc++") 392 return ToolChain::CST_Libstdcxx; 393 else 394 getDriver().Diag(diag::err_drv_invalid_stdlib_name) 395 << A->getAsString(Args); 396 } 397 return ToolChain::CST_Libcxx; 398 } 399 400 void WebAssembly::AddClangSystemIncludeArgs(const ArgList &DriverArgs, 401 ArgStringList &CC1Args) const { 402 if (DriverArgs.hasArg(clang::driver::options::OPT_nostdinc)) 403 return; 404 405 const Driver &D = getDriver(); 406 407 if (!DriverArgs.hasArg(options::OPT_nobuiltininc)) { 408 SmallString<128> P(D.ResourceDir); 409 llvm::sys::path::append(P, "include"); 410 addSystemInclude(DriverArgs, CC1Args, P); 411 } 412 413 if (DriverArgs.hasArg(options::OPT_nostdlibinc)) 414 return; 415 416 // Check for configure-time C include directories. 417 StringRef CIncludeDirs(C_INCLUDE_DIRS); 418 if (CIncludeDirs != "") { 419 SmallVector<StringRef, 5> dirs; 420 CIncludeDirs.split(dirs, ":"); 421 for (StringRef dir : dirs) { 422 StringRef Prefix = 423 llvm::sys::path::is_absolute(dir) ? "" : StringRef(D.SysRoot); 424 addExternCSystemInclude(DriverArgs, CC1Args, Prefix + dir); 425 } 426 return; 427 } 428 429 if (getTriple().getOS() != llvm::Triple::UnknownOS) { 430 const std::string MultiarchTriple = 431 getMultiarchTriple(D, getTriple(), D.SysRoot); 432 addSystemInclude(DriverArgs, CC1Args, D.SysRoot + "/include/" + MultiarchTriple); 433 } 434 addSystemInclude(DriverArgs, CC1Args, D.SysRoot + "/include"); 435 } 436 437 void WebAssembly::AddClangCXXStdlibIncludeArgs(const ArgList &DriverArgs, 438 ArgStringList &CC1Args) const { 439 440 if (DriverArgs.hasArg(options::OPT_nostdlibinc, options::OPT_nostdinc, 441 options::OPT_nostdincxx)) 442 return; 443 444 switch (GetCXXStdlibType(DriverArgs)) { 445 case ToolChain::CST_Libcxx: 446 addLibCxxIncludePaths(DriverArgs, CC1Args); 447 break; 448 case ToolChain::CST_Libstdcxx: 449 addLibStdCXXIncludePaths(DriverArgs, CC1Args); 450 break; 451 } 452 } 453 454 void WebAssembly::AddCXXStdlibLibArgs(const llvm::opt::ArgList &Args, 455 llvm::opt::ArgStringList &CmdArgs) const { 456 457 switch (GetCXXStdlibType(Args)) { 458 case ToolChain::CST_Libcxx: 459 CmdArgs.push_back("-lc++"); 460 if (Args.hasArg(options::OPT_fexperimental_library)) 461 CmdArgs.push_back("-lc++experimental"); 462 CmdArgs.push_back("-lc++abi"); 463 break; 464 case ToolChain::CST_Libstdcxx: 465 CmdArgs.push_back("-lstdc++"); 466 break; 467 } 468 } 469 470 SanitizerMask WebAssembly::getSupportedSanitizers() const { 471 SanitizerMask Res = ToolChain::getSupportedSanitizers(); 472 if (getTriple().isOSEmscripten()) { 473 Res |= SanitizerKind::Vptr | SanitizerKind::Leak | SanitizerKind::Address; 474 } 475 // -fsanitize=function places two words before the function label, which are 476 // -unsupported. 477 Res &= ~SanitizerKind::Function; 478 return Res; 479 } 480 481 Tool *WebAssembly::buildLinker() const { 482 return new tools::wasm::Linker(*this); 483 } 484 485 void WebAssembly::addLibCxxIncludePaths( 486 const llvm::opt::ArgList &DriverArgs, 487 llvm::opt::ArgStringList &CC1Args) const { 488 const Driver &D = getDriver(); 489 std::string SysRoot = computeSysRoot(); 490 std::string LibPath = SysRoot + "/include"; 491 const std::string MultiarchTriple = 492 getMultiarchTriple(D, getTriple(), SysRoot); 493 bool IsKnownOs = (getTriple().getOS() != llvm::Triple::UnknownOS); 494 495 std::string Version = detectLibcxxVersion(LibPath); 496 if (Version.empty()) 497 return; 498 499 // First add the per-target include path if the OS is known. 500 if (IsKnownOs) { 501 std::string TargetDir = LibPath + "/" + MultiarchTriple + "/c++/" + Version; 502 addSystemInclude(DriverArgs, CC1Args, TargetDir); 503 } 504 505 // Second add the generic one. 506 addSystemInclude(DriverArgs, CC1Args, LibPath + "/c++/" + Version); 507 } 508 509 void WebAssembly::addLibStdCXXIncludePaths( 510 const llvm::opt::ArgList &DriverArgs, 511 llvm::opt::ArgStringList &CC1Args) const { 512 // We cannot use GCCInstallationDetector here as the sysroot usually does 513 // not contain a full GCC installation. 514 // Instead, we search the given sysroot for /usr/include/xx, similar 515 // to how we do it for libc++. 516 const Driver &D = getDriver(); 517 std::string SysRoot = computeSysRoot(); 518 std::string LibPath = SysRoot + "/include"; 519 const std::string MultiarchTriple = 520 getMultiarchTriple(D, getTriple(), SysRoot); 521 bool IsKnownOs = (getTriple().getOS() != llvm::Triple::UnknownOS); 522 523 // This is similar to detectLibcxxVersion() 524 std::string Version; 525 { 526 std::error_code EC; 527 Generic_GCC::GCCVersion MaxVersion = 528 Generic_GCC::GCCVersion::Parse("0.0.0"); 529 SmallString<128> Path(LibPath); 530 llvm::sys::path::append(Path, "c++"); 531 for (llvm::vfs::directory_iterator LI = getVFS().dir_begin(Path, EC), LE; 532 !EC && LI != LE; LI = LI.increment(EC)) { 533 StringRef VersionText = llvm::sys::path::filename(LI->path()); 534 if (VersionText[0] != 'v') { 535 auto Version = Generic_GCC::GCCVersion::Parse(VersionText); 536 if (Version > MaxVersion) 537 MaxVersion = Version; 538 } 539 } 540 if (MaxVersion.Major > 0) 541 Version = MaxVersion.Text; 542 } 543 544 if (Version.empty()) 545 return; 546 547 // First add the per-target include path if the OS is known. 548 if (IsKnownOs) { 549 std::string TargetDir = LibPath + "/c++/" + Version + "/" + MultiarchTriple; 550 addSystemInclude(DriverArgs, CC1Args, TargetDir); 551 } 552 553 // Second add the generic one. 554 addSystemInclude(DriverArgs, CC1Args, LibPath + "/c++/" + Version); 555 // Third the backward one. 556 addSystemInclude(DriverArgs, CC1Args, LibPath + "/c++/" + Version + "/backward"); 557 } 558