xref: /freebsd/contrib/llvm-project/clang/lib/Driver/ToolChains/Linux.cpp (revision 47ef2a131091508e049ab10cad7f91a3c1342cd9)
1 //===--- Linux.h - Linux ToolChain Implementations --------------*- 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 "Linux.h"
10 #include "Arch/ARM.h"
11 #include "Arch/LoongArch.h"
12 #include "Arch/Mips.h"
13 #include "Arch/PPC.h"
14 #include "Arch/RISCV.h"
15 #include "CommonArgs.h"
16 #include "clang/Config/config.h"
17 #include "clang/Driver/Distro.h"
18 #include "clang/Driver/Driver.h"
19 #include "clang/Driver/Options.h"
20 #include "clang/Driver/SanitizerArgs.h"
21 #include "llvm/Option/ArgList.h"
22 #include "llvm/ProfileData/InstrProf.h"
23 #include "llvm/Support/Path.h"
24 #include "llvm/Support/ScopedPrinter.h"
25 #include "llvm/Support/VirtualFileSystem.h"
26 #include <system_error>
27 
28 using namespace clang::driver;
29 using namespace clang::driver::toolchains;
30 using namespace clang;
31 using namespace llvm::opt;
32 
33 using tools::addPathIfExists;
34 
35 /// Get our best guess at the multiarch triple for a target.
36 ///
37 /// Debian-based systems are starting to use a multiarch setup where they use
38 /// a target-triple directory in the library and header search paths.
39 /// Unfortunately, this triple does not align with the vanilla target triple,
40 /// so we provide a rough mapping here.
41 std::string Linux::getMultiarchTriple(const Driver &D,
42                                       const llvm::Triple &TargetTriple,
43                                       StringRef SysRoot) const {
44   llvm::Triple::EnvironmentType TargetEnvironment =
45       TargetTriple.getEnvironment();
46   bool IsAndroid = TargetTriple.isAndroid();
47   bool IsMipsR6 = TargetTriple.getSubArch() == llvm::Triple::MipsSubArch_r6;
48   bool IsMipsN32Abi = TargetTriple.getEnvironment() == llvm::Triple::GNUABIN32;
49 
50   // For most architectures, just use whatever we have rather than trying to be
51   // clever.
52   switch (TargetTriple.getArch()) {
53   default:
54     break;
55 
56   // We use the existence of '/lib/<triple>' as a directory to detect some
57   // common linux triples that don't quite match the Clang triple for both
58   // 32-bit and 64-bit targets. Multiarch fixes its install triples to these
59   // regardless of what the actual target triple is.
60   case llvm::Triple::arm:
61   case llvm::Triple::thumb:
62     if (IsAndroid)
63       return "arm-linux-androideabi";
64     if (TargetEnvironment == llvm::Triple::GNUEABIHF ||
65         TargetEnvironment == llvm::Triple::MuslEABIHF ||
66         TargetEnvironment == llvm::Triple::EABIHF)
67       return "arm-linux-gnueabihf";
68     return "arm-linux-gnueabi";
69   case llvm::Triple::armeb:
70   case llvm::Triple::thumbeb:
71     if (TargetEnvironment == llvm::Triple::GNUEABIHF ||
72         TargetEnvironment == llvm::Triple::MuslEABIHF ||
73         TargetEnvironment == llvm::Triple::EABIHF)
74       return "armeb-linux-gnueabihf";
75     return "armeb-linux-gnueabi";
76   case llvm::Triple::x86:
77     if (IsAndroid)
78       return "i686-linux-android";
79     return "i386-linux-gnu";
80   case llvm::Triple::x86_64:
81     if (IsAndroid)
82       return "x86_64-linux-android";
83     if (TargetEnvironment == llvm::Triple::GNUX32)
84       return "x86_64-linux-gnux32";
85     return "x86_64-linux-gnu";
86   case llvm::Triple::aarch64:
87     if (IsAndroid)
88       return "aarch64-linux-android";
89     if (hasEffectiveTriple() &&
90         getEffectiveTriple().getEnvironment() == llvm::Triple::PAuthTest)
91       return "aarch64-linux-pauthtest";
92     return "aarch64-linux-gnu";
93   case llvm::Triple::aarch64_be:
94     return "aarch64_be-linux-gnu";
95 
96   case llvm::Triple::loongarch64: {
97     const char *Libc;
98     const char *FPFlavor;
99 
100     if (TargetTriple.isGNUEnvironment()) {
101       Libc = "gnu";
102     } else if (TargetTriple.isMusl()) {
103       Libc = "musl";
104     } else {
105       return TargetTriple.str();
106     }
107 
108     switch (TargetEnvironment) {
109     default:
110       return TargetTriple.str();
111     case llvm::Triple::GNUSF:
112       FPFlavor = "sf";
113       break;
114     case llvm::Triple::GNUF32:
115       FPFlavor = "f32";
116       break;
117     case llvm::Triple::GNU:
118     case llvm::Triple::GNUF64:
119       // This was going to be "f64" in an earlier Toolchain Conventions
120       // revision, but starting from Feb 2023 the F64 ABI variants are
121       // unmarked in their canonical forms.
122       FPFlavor = "";
123       break;
124     }
125 
126     return (Twine("loongarch64-linux-") + Libc + FPFlavor).str();
127   }
128 
129   case llvm::Triple::m68k:
130     return "m68k-linux-gnu";
131 
132   case llvm::Triple::mips:
133     return IsMipsR6 ? "mipsisa32r6-linux-gnu" : "mips-linux-gnu";
134   case llvm::Triple::mipsel:
135     return IsMipsR6 ? "mipsisa32r6el-linux-gnu" : "mipsel-linux-gnu";
136   case llvm::Triple::mips64: {
137     std::string MT = std::string(IsMipsR6 ? "mipsisa64r6" : "mips64") +
138                      "-linux-" + (IsMipsN32Abi ? "gnuabin32" : "gnuabi64");
139     if (D.getVFS().exists(concat(SysRoot, "/lib", MT)))
140       return MT;
141     if (D.getVFS().exists(concat(SysRoot, "/lib/mips64-linux-gnu")))
142       return "mips64-linux-gnu";
143     break;
144   }
145   case llvm::Triple::mips64el: {
146     std::string MT = std::string(IsMipsR6 ? "mipsisa64r6el" : "mips64el") +
147                      "-linux-" + (IsMipsN32Abi ? "gnuabin32" : "gnuabi64");
148     if (D.getVFS().exists(concat(SysRoot, "/lib", MT)))
149       return MT;
150     if (D.getVFS().exists(concat(SysRoot, "/lib/mips64el-linux-gnu")))
151       return "mips64el-linux-gnu";
152     break;
153   }
154   case llvm::Triple::ppc:
155     if (D.getVFS().exists(concat(SysRoot, "/lib/powerpc-linux-gnuspe")))
156       return "powerpc-linux-gnuspe";
157     return "powerpc-linux-gnu";
158   case llvm::Triple::ppcle:
159     return "powerpcle-linux-gnu";
160   case llvm::Triple::ppc64:
161     return "powerpc64-linux-gnu";
162   case llvm::Triple::ppc64le:
163     return "powerpc64le-linux-gnu";
164   case llvm::Triple::riscv64:
165     if (IsAndroid)
166       return "riscv64-linux-android";
167     return "riscv64-linux-gnu";
168   case llvm::Triple::sparc:
169     return "sparc-linux-gnu";
170   case llvm::Triple::sparcv9:
171     return "sparc64-linux-gnu";
172   case llvm::Triple::systemz:
173     return "s390x-linux-gnu";
174   }
175   return TargetTriple.str();
176 }
177 
178 static StringRef getOSLibDir(const llvm::Triple &Triple, const ArgList &Args) {
179   if (Triple.isMIPS()) {
180     if (Triple.isAndroid()) {
181       StringRef CPUName;
182       StringRef ABIName;
183       tools::mips::getMipsCPUAndABI(Args, Triple, CPUName, ABIName);
184       if (CPUName == "mips32r6")
185         return "libr6";
186       if (CPUName == "mips32r2")
187         return "libr2";
188     }
189     // lib32 directory has a special meaning on MIPS targets.
190     // It contains N32 ABI binaries. Use this folder if produce
191     // code for N32 ABI only.
192     if (tools::mips::hasMipsAbiArg(Args, "n32"))
193       return "lib32";
194     return Triple.isArch32Bit() ? "lib" : "lib64";
195   }
196 
197   // It happens that only x86, PPC and SPARC use the 'lib32' variant of
198   // oslibdir, and using that variant while targeting other architectures causes
199   // problems because the libraries are laid out in shared system roots that
200   // can't cope with a 'lib32' library search path being considered. So we only
201   // enable them when we know we may need it.
202   //
203   // FIXME: This is a bit of a hack. We should really unify this code for
204   // reasoning about oslibdir spellings with the lib dir spellings in the
205   // GCCInstallationDetector, but that is a more significant refactoring.
206   if (Triple.getArch() == llvm::Triple::x86 || Triple.isPPC32() ||
207       Triple.getArch() == llvm::Triple::sparc)
208     return "lib32";
209 
210   if (Triple.getArch() == llvm::Triple::x86_64 && Triple.isX32())
211     return "libx32";
212 
213   if (Triple.getArch() == llvm::Triple::riscv32)
214     return "lib32";
215 
216   return Triple.isArch32Bit() ? "lib" : "lib64";
217 }
218 
219 Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
220     : Generic_ELF(D, Triple, Args) {
221   GCCInstallation.init(Triple, Args);
222   Multilibs = GCCInstallation.getMultilibs();
223   SelectedMultilibs.assign({GCCInstallation.getMultilib()});
224   llvm::Triple::ArchType Arch = Triple.getArch();
225   std::string SysRoot = computeSysRoot();
226   ToolChain::path_list &PPaths = getProgramPaths();
227 
228   Generic_GCC::PushPPaths(PPaths);
229 
230   Distro Distro(D.getVFS(), Triple);
231 
232   if (Distro.IsAlpineLinux() || Triple.isAndroid()) {
233     ExtraOpts.push_back("-z");
234     ExtraOpts.push_back("now");
235   }
236 
237   if (Distro.IsOpenSUSE() || Distro.IsUbuntu() || Distro.IsAlpineLinux() ||
238       Triple.isAndroid()) {
239     ExtraOpts.push_back("-z");
240     ExtraOpts.push_back("relro");
241   }
242 
243   // Note, lld from 11 onwards default max-page-size to 65536 for both ARM and
244   // AArch64.
245   if (Triple.isAndroid()) {
246     if (Triple.isARM()) {
247       // Android ARM uses max-page-size=4096 to reduce VMA usage.
248       ExtraOpts.push_back("-z");
249       ExtraOpts.push_back("max-page-size=4096");
250     } else if (Triple.isAArch64() || Triple.getArch() == llvm::Triple::x86_64) {
251       // Android AArch64 uses max-page-size=16384 to support 4k/16k page sizes.
252       // Android emulates a 16k page size for app testing on x86_64 machines.
253       ExtraOpts.push_back("-z");
254       ExtraOpts.push_back("max-page-size=16384");
255     }
256   }
257 
258   if (GCCInstallation.getParentLibPath().contains("opt/rh/"))
259     // With devtoolset on RHEL, we want to add a bin directory that is relative
260     // to the detected gcc install, because if we are using devtoolset gcc then
261     // we want to use other tools from devtoolset (e.g. ld) instead of the
262     // standard system tools.
263     PPaths.push_back(Twine(GCCInstallation.getParentLibPath() +
264                      "/../bin").str());
265 
266   if (Arch == llvm::Triple::arm || Arch == llvm::Triple::thumb)
267     ExtraOpts.push_back("-X");
268 
269   const bool IsAndroid = Triple.isAndroid();
270   const bool IsMips = Triple.isMIPS();
271   const bool IsHexagon = Arch == llvm::Triple::hexagon;
272   const bool IsRISCV = Triple.isRISCV();
273   const bool IsCSKY = Triple.isCSKY();
274 
275   if (IsCSKY && !SelectedMultilibs.empty())
276     SysRoot = SysRoot + SelectedMultilibs.back().osSuffix();
277 
278   if ((IsMips || IsCSKY) && !SysRoot.empty())
279     ExtraOpts.push_back("--sysroot=" + SysRoot);
280 
281   // Do not use 'gnu' hash style for Mips targets because .gnu.hash
282   // and the MIPS ABI require .dynsym to be sorted in different ways.
283   // .gnu.hash needs symbols to be grouped by hash code whereas the MIPS
284   // ABI requires a mapping between the GOT and the symbol table.
285   // Android loader does not support .gnu.hash until API 23.
286   // Hexagon linker/loader does not support .gnu.hash
287   if (!IsMips && !IsHexagon) {
288     if (Distro.IsOpenSUSE() || Distro == Distro::UbuntuLucid ||
289         Distro == Distro::UbuntuJaunty || Distro == Distro::UbuntuKarmic ||
290         (IsAndroid && Triple.isAndroidVersionLT(23)))
291       ExtraOpts.push_back("--hash-style=both");
292     else
293       ExtraOpts.push_back("--hash-style=gnu");
294   }
295 
296 #ifdef ENABLE_LINKER_BUILD_ID
297   ExtraOpts.push_back("--build-id");
298 #endif
299 
300   // The selection of paths to try here is designed to match the patterns which
301   // the GCC driver itself uses, as this is part of the GCC-compatible driver.
302   // This was determined by running GCC in a fake filesystem, creating all
303   // possible permutations of these directories, and seeing which ones it added
304   // to the link paths.
305   path_list &Paths = getFilePaths();
306 
307   const std::string OSLibDir = std::string(getOSLibDir(Triple, Args));
308   const std::string MultiarchTriple = getMultiarchTriple(D, Triple, SysRoot);
309 
310   // mips32: Debian multilib, we use /libo32, while in other case, /lib is
311   // used. We need add both libo32 and /lib.
312   if (Arch == llvm::Triple::mips || Arch == llvm::Triple::mipsel) {
313     Generic_GCC::AddMultilibPaths(D, SysRoot, "libo32", MultiarchTriple, Paths);
314     addPathIfExists(D, concat(SysRoot, "/libo32"), Paths);
315     addPathIfExists(D, concat(SysRoot, "/usr/libo32"), Paths);
316   }
317   Generic_GCC::AddMultilibPaths(D, SysRoot, OSLibDir, MultiarchTriple, Paths);
318 
319   addPathIfExists(D, concat(SysRoot, "/lib", MultiarchTriple), Paths);
320   addPathIfExists(D, concat(SysRoot, "/lib/..", OSLibDir), Paths);
321 
322   if (IsAndroid) {
323     // Android sysroots contain a library directory for each supported OS
324     // version as well as some unversioned libraries in the usual multiarch
325     // directory.
326     addPathIfExists(
327         D,
328         concat(SysRoot, "/usr/lib", MultiarchTriple,
329                llvm::to_string(Triple.getEnvironmentVersion().getMajor())),
330         Paths);
331   }
332 
333   addPathIfExists(D, concat(SysRoot, "/usr/lib", MultiarchTriple), Paths);
334   // 64-bit OpenEmbedded sysroots may not have a /usr/lib dir. So they cannot
335   // find /usr/lib64 as it is referenced as /usr/lib/../lib64. So we handle
336   // this here.
337   if (Triple.getVendor() == llvm::Triple::OpenEmbedded &&
338       Triple.isArch64Bit())
339     addPathIfExists(D, concat(SysRoot, "/usr", OSLibDir), Paths);
340   else
341     addPathIfExists(D, concat(SysRoot, "/usr/lib/..", OSLibDir), Paths);
342   if (IsRISCV) {
343     StringRef ABIName = tools::riscv::getRISCVABI(Args, Triple);
344     addPathIfExists(D, concat(SysRoot, "/", OSLibDir, ABIName), Paths);
345     addPathIfExists(D, concat(SysRoot, "/usr", OSLibDir, ABIName), Paths);
346   }
347 
348   Generic_GCC::AddMultiarchPaths(D, SysRoot, OSLibDir, Paths);
349 
350   addPathIfExists(D, concat(SysRoot, "/lib"), Paths);
351   addPathIfExists(D, concat(SysRoot, "/usr/lib"), Paths);
352 }
353 
354 ToolChain::RuntimeLibType Linux::GetDefaultRuntimeLibType() const {
355   if (getTriple().isAndroid())
356     return ToolChain::RLT_CompilerRT;
357   return Generic_ELF::GetDefaultRuntimeLibType();
358 }
359 
360 unsigned Linux::GetDefaultDwarfVersion() const {
361   if (getTriple().isAndroid())
362     return 4;
363   return ToolChain::GetDefaultDwarfVersion();
364 }
365 
366 ToolChain::CXXStdlibType Linux::GetDefaultCXXStdlibType() const {
367   if (getTriple().isAndroid())
368     return ToolChain::CST_Libcxx;
369   return ToolChain::CST_Libstdcxx;
370 }
371 
372 bool Linux::HasNativeLLVMSupport() const { return true; }
373 
374 Tool *Linux::buildLinker() const { return new tools::gnutools::Linker(*this); }
375 
376 Tool *Linux::buildStaticLibTool() const {
377   return new tools::gnutools::StaticLibTool(*this);
378 }
379 
380 Tool *Linux::buildAssembler() const {
381   return new tools::gnutools::Assembler(*this);
382 }
383 
384 std::string Linux::computeSysRoot() const {
385   if (!getDriver().SysRoot.empty())
386     return getDriver().SysRoot;
387 
388   if (getTriple().isAndroid()) {
389     // Android toolchains typically include a sysroot at ../sysroot relative to
390     // the clang binary.
391     const StringRef ClangDir = getDriver().Dir;
392     std::string AndroidSysRootPath = (ClangDir + "/../sysroot").str();
393     if (getVFS().exists(AndroidSysRootPath))
394       return AndroidSysRootPath;
395   }
396 
397   if (getTriple().isCSKY()) {
398     // CSKY toolchains use different names for sysroot folder.
399     if (!GCCInstallation.isValid())
400       return std::string();
401     // GCCInstallation.getInstallPath() =
402     //   $GCCToolchainPath/lib/gcc/csky-linux-gnuabiv2/6.3.0
403     // Path = $GCCToolchainPath/csky-linux-gnuabiv2/libc
404     std::string Path = (GCCInstallation.getInstallPath() + "/../../../../" +
405                         GCCInstallation.getTriple().str() + "/libc")
406                            .str();
407     if (getVFS().exists(Path))
408       return Path;
409     return std::string();
410   }
411 
412   if (!GCCInstallation.isValid() || !getTriple().isMIPS())
413     return std::string();
414 
415   // Standalone MIPS toolchains use different names for sysroot folder
416   // and put it into different places. Here we try to check some known
417   // variants.
418 
419   const StringRef InstallDir = GCCInstallation.getInstallPath();
420   const StringRef TripleStr = GCCInstallation.getTriple().str();
421   const Multilib &Multilib = GCCInstallation.getMultilib();
422 
423   std::string Path =
424       (InstallDir + "/../../../../" + TripleStr + "/libc" + Multilib.osSuffix())
425           .str();
426 
427   if (getVFS().exists(Path))
428     return Path;
429 
430   Path = (InstallDir + "/../../../../sysroot" + Multilib.osSuffix()).str();
431 
432   if (getVFS().exists(Path))
433     return Path;
434 
435   return std::string();
436 }
437 
438 std::string Linux::getDynamicLinker(const ArgList &Args) const {
439   const llvm::Triple::ArchType Arch = getArch();
440   const llvm::Triple &Triple = getTriple();
441 
442   const Distro Distro(getDriver().getVFS(), Triple);
443 
444   if (Triple.isAndroid()) {
445     if (getSanitizerArgs(Args).needsHwasanRt() &&
446         !Triple.isAndroidVersionLT(34) && Triple.isArch64Bit()) {
447       // On Android 14 and newer, there is a special linker_hwasan64 that
448       // allows to run HWASan binaries on non-HWASan system images. This
449       // is also available on HWASan system images, so we can just always
450       // use that instead.
451       return "/system/bin/linker_hwasan64";
452     }
453     return Triple.isArch64Bit() ? "/system/bin/linker64" : "/system/bin/linker";
454   }
455   if (Triple.isMusl()) {
456     std::string ArchName;
457     bool IsArm = false;
458 
459     switch (Arch) {
460     case llvm::Triple::arm:
461     case llvm::Triple::thumb:
462       ArchName = "arm";
463       IsArm = true;
464       break;
465     case llvm::Triple::armeb:
466     case llvm::Triple::thumbeb:
467       ArchName = "armeb";
468       IsArm = true;
469       break;
470     case llvm::Triple::x86:
471       ArchName = "i386";
472       break;
473     case llvm::Triple::x86_64:
474       ArchName = Triple.isX32() ? "x32" : Triple.getArchName().str();
475       break;
476     default:
477       ArchName = Triple.getArchName().str();
478     }
479     if (IsArm &&
480         (Triple.getEnvironment() == llvm::Triple::MuslEABIHF ||
481          tools::arm::getARMFloatABI(*this, Args) == tools::arm::FloatABI::Hard))
482       ArchName += "hf";
483     if (Arch == llvm::Triple::ppc &&
484         Triple.getSubArch() == llvm::Triple::PPCSubArch_spe)
485       ArchName = "powerpc-sf";
486 
487     return "/lib/ld-musl-" + ArchName + ".so.1";
488   }
489 
490   std::string LibDir;
491   std::string Loader;
492 
493   switch (Arch) {
494   default:
495     llvm_unreachable("unsupported architecture");
496 
497   case llvm::Triple::aarch64:
498     LibDir = "lib";
499     Loader = "ld-linux-aarch64.so.1";
500     break;
501   case llvm::Triple::aarch64_be:
502     LibDir = "lib";
503     Loader = "ld-linux-aarch64_be.so.1";
504     break;
505   case llvm::Triple::arm:
506   case llvm::Triple::thumb:
507   case llvm::Triple::armeb:
508   case llvm::Triple::thumbeb: {
509     const bool HF =
510         Triple.getEnvironment() == llvm::Triple::GNUEABIHF ||
511         tools::arm::getARMFloatABI(*this, Args) == tools::arm::FloatABI::Hard;
512 
513     LibDir = "lib";
514     Loader = HF ? "ld-linux-armhf.so.3" : "ld-linux.so.3";
515     break;
516   }
517   case llvm::Triple::loongarch32: {
518     LibDir = "lib32";
519     Loader =
520         ("ld-linux-loongarch-" +
521          tools::loongarch::getLoongArchABI(getDriver(), Args, Triple) + ".so.1")
522             .str();
523     break;
524   }
525   case llvm::Triple::loongarch64: {
526     LibDir = "lib64";
527     Loader =
528         ("ld-linux-loongarch-" +
529          tools::loongarch::getLoongArchABI(getDriver(), Args, Triple) + ".so.1")
530             .str();
531     break;
532   }
533   case llvm::Triple::m68k:
534     LibDir = "lib";
535     Loader = "ld.so.1";
536     break;
537   case llvm::Triple::mips:
538   case llvm::Triple::mipsel:
539   case llvm::Triple::mips64:
540   case llvm::Triple::mips64el: {
541     bool IsNaN2008 = tools::mips::isNaN2008(getDriver(), Args, Triple);
542 
543     LibDir = "lib" + tools::mips::getMipsABILibSuffix(Args, Triple);
544 
545     if (tools::mips::isUCLibc(Args))
546       Loader = IsNaN2008 ? "ld-uClibc-mipsn8.so.0" : "ld-uClibc.so.0";
547     else if (!Triple.hasEnvironment() &&
548              Triple.getVendor() == llvm::Triple::VendorType::MipsTechnologies)
549       Loader =
550           Triple.isLittleEndian() ? "ld-musl-mipsel.so.1" : "ld-musl-mips.so.1";
551     else
552       Loader = IsNaN2008 ? "ld-linux-mipsn8.so.1" : "ld.so.1";
553 
554     break;
555   }
556   case llvm::Triple::ppc:
557     LibDir = "lib";
558     Loader = "ld.so.1";
559     break;
560   case llvm::Triple::ppcle:
561     LibDir = "lib";
562     Loader = "ld.so.1";
563     break;
564   case llvm::Triple::ppc64:
565     LibDir = "lib64";
566     Loader =
567         (tools::ppc::hasPPCAbiArg(Args, "elfv2")) ? "ld64.so.2" : "ld64.so.1";
568     break;
569   case llvm::Triple::ppc64le:
570     LibDir = "lib64";
571     Loader =
572         (tools::ppc::hasPPCAbiArg(Args, "elfv1")) ? "ld64.so.1" : "ld64.so.2";
573     break;
574   case llvm::Triple::riscv32:
575   case llvm::Triple::riscv64: {
576     StringRef ArchName = llvm::Triple::getArchTypeName(Arch);
577     StringRef ABIName = tools::riscv::getRISCVABI(Args, Triple);
578     LibDir = "lib";
579     Loader = ("ld-linux-" + ArchName + "-" + ABIName + ".so.1").str();
580     break;
581   }
582   case llvm::Triple::sparc:
583   case llvm::Triple::sparcel:
584     LibDir = "lib";
585     Loader = "ld-linux.so.2";
586     break;
587   case llvm::Triple::sparcv9:
588     LibDir = "lib64";
589     Loader = "ld-linux.so.2";
590     break;
591   case llvm::Triple::systemz:
592     LibDir = "lib";
593     Loader = "ld64.so.1";
594     break;
595   case llvm::Triple::x86:
596     LibDir = "lib";
597     Loader = "ld-linux.so.2";
598     break;
599   case llvm::Triple::x86_64: {
600     bool X32 = Triple.isX32();
601 
602     LibDir = X32 ? "libx32" : "lib64";
603     Loader = X32 ? "ld-linux-x32.so.2" : "ld-linux-x86-64.so.2";
604     break;
605   }
606   case llvm::Triple::ve:
607     return "/opt/nec/ve/lib/ld-linux-ve.so.1";
608   case llvm::Triple::csky: {
609     LibDir = "lib";
610     Loader = "ld.so.1";
611     break;
612   }
613   }
614 
615   if (Distro == Distro::Exherbo &&
616       (Triple.getVendor() == llvm::Triple::UnknownVendor ||
617        Triple.getVendor() == llvm::Triple::PC))
618     return "/usr/" + Triple.str() + "/lib/" + Loader;
619   return "/" + LibDir + "/" + Loader;
620 }
621 
622 void Linux::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
623                                       ArgStringList &CC1Args) const {
624   const Driver &D = getDriver();
625   std::string SysRoot = computeSysRoot();
626 
627   if (DriverArgs.hasArg(clang::driver::options::OPT_nostdinc))
628     return;
629 
630   // Add 'include' in the resource directory, which is similar to
631   // GCC_INCLUDE_DIR (private headers) in GCC. Note: the include directory
632   // contains some files conflicting with system /usr/include. musl systems
633   // prefer the /usr/include copies which are more relevant.
634   SmallString<128> ResourceDirInclude(D.ResourceDir);
635   llvm::sys::path::append(ResourceDirInclude, "include");
636   if (!DriverArgs.hasArg(options::OPT_nobuiltininc) &&
637       (!getTriple().isMusl() || DriverArgs.hasArg(options::OPT_nostdlibinc)))
638     addSystemInclude(DriverArgs, CC1Args, ResourceDirInclude);
639 
640   if (DriverArgs.hasArg(options::OPT_nostdlibinc))
641     return;
642 
643   // LOCAL_INCLUDE_DIR
644   addSystemInclude(DriverArgs, CC1Args, concat(SysRoot, "/usr/local/include"));
645   // TOOL_INCLUDE_DIR
646   AddMultilibIncludeArgs(DriverArgs, CC1Args);
647 
648   // Check for configure-time C include directories.
649   StringRef CIncludeDirs(C_INCLUDE_DIRS);
650   if (CIncludeDirs != "") {
651     SmallVector<StringRef, 5> dirs;
652     CIncludeDirs.split(dirs, ":");
653     for (StringRef dir : dirs) {
654       StringRef Prefix =
655           llvm::sys::path::is_absolute(dir) ? "" : StringRef(SysRoot);
656       addExternCSystemInclude(DriverArgs, CC1Args, Prefix + dir);
657     }
658     return;
659   }
660 
661   // On systems using multiarch and Android, add /usr/include/$triple before
662   // /usr/include.
663   std::string MultiarchIncludeDir = getMultiarchTriple(D, getTriple(), SysRoot);
664   if (!MultiarchIncludeDir.empty() &&
665       D.getVFS().exists(concat(SysRoot, "/usr/include", MultiarchIncludeDir)))
666     addExternCSystemInclude(
667         DriverArgs, CC1Args,
668         concat(SysRoot, "/usr/include", MultiarchIncludeDir));
669 
670   if (getTriple().getOS() == llvm::Triple::RTEMS)
671     return;
672 
673   // Add an include of '/include' directly. This isn't provided by default by
674   // system GCCs, but is often used with cross-compiling GCCs, and harmless to
675   // add even when Clang is acting as-if it were a system compiler.
676   addExternCSystemInclude(DriverArgs, CC1Args, concat(SysRoot, "/include"));
677 
678   addExternCSystemInclude(DriverArgs, CC1Args, concat(SysRoot, "/usr/include"));
679 
680   if (!DriverArgs.hasArg(options::OPT_nobuiltininc) && getTriple().isMusl())
681     addSystemInclude(DriverArgs, CC1Args, ResourceDirInclude);
682 }
683 
684 void Linux::addLibStdCxxIncludePaths(const llvm::opt::ArgList &DriverArgs,
685                                      llvm::opt::ArgStringList &CC1Args) const {
686   // We need a detected GCC installation on Linux to provide libstdc++'s
687   // headers in odd Linuxish places.
688   if (!GCCInstallation.isValid())
689     return;
690 
691   // Detect Debian g++-multiarch-incdir.diff.
692   StringRef TripleStr = GCCInstallation.getTriple().str();
693   StringRef DebianMultiarch =
694       GCCInstallation.getTriple().getArch() == llvm::Triple::x86
695           ? "i386-linux-gnu"
696           : TripleStr;
697 
698   // Try generic GCC detection first.
699   if (Generic_GCC::addGCCLibStdCxxIncludePaths(DriverArgs, CC1Args,
700                                                DebianMultiarch))
701     return;
702 
703   StringRef LibDir = GCCInstallation.getParentLibPath();
704   const Multilib &Multilib = GCCInstallation.getMultilib();
705   const GCCVersion &Version = GCCInstallation.getVersion();
706 
707   const std::string LibStdCXXIncludePathCandidates[] = {
708       // Android standalone toolchain has C++ headers in yet another place.
709       LibDir.str() + "/../" + TripleStr.str() + "/include/c++/" + Version.Text,
710       // Freescale SDK C++ headers are directly in <sysroot>/usr/include/c++,
711       // without a subdirectory corresponding to the gcc version.
712       LibDir.str() + "/../include/c++",
713       // Cray's gcc installation puts headers under "g++" without a
714       // version suffix.
715       LibDir.str() + "/../include/g++",
716   };
717 
718   for (const auto &IncludePath : LibStdCXXIncludePathCandidates) {
719     if (addLibStdCXXIncludePaths(IncludePath, TripleStr,
720                                  Multilib.includeSuffix(), DriverArgs, CC1Args))
721       break;
722   }
723 }
724 
725 void Linux::AddCudaIncludeArgs(const ArgList &DriverArgs,
726                                ArgStringList &CC1Args) const {
727   CudaInstallation->AddCudaIncludeArgs(DriverArgs, CC1Args);
728 }
729 
730 void Linux::AddHIPIncludeArgs(const ArgList &DriverArgs,
731                               ArgStringList &CC1Args) const {
732   RocmInstallation->AddHIPIncludeArgs(DriverArgs, CC1Args);
733 }
734 
735 void Linux::AddHIPRuntimeLibArgs(const ArgList &Args,
736                                  ArgStringList &CmdArgs) const {
737   CmdArgs.push_back(
738       Args.MakeArgString(StringRef("-L") + RocmInstallation->getLibPath()));
739 
740   if (Args.hasFlag(options::OPT_frtlib_add_rpath,
741                    options::OPT_fno_rtlib_add_rpath, false))
742     CmdArgs.append(
743         {"-rpath", Args.MakeArgString(RocmInstallation->getLibPath())});
744 
745   CmdArgs.push_back("-lamdhip64");
746 }
747 
748 void Linux::AddIAMCUIncludeArgs(const ArgList &DriverArgs,
749                                 ArgStringList &CC1Args) const {
750   if (GCCInstallation.isValid()) {
751     CC1Args.push_back("-isystem");
752     CC1Args.push_back(DriverArgs.MakeArgString(
753         GCCInstallation.getParentLibPath() + "/../" +
754         GCCInstallation.getTriple().str() + "/include"));
755   }
756 }
757 
758 bool Linux::isPIEDefault(const llvm::opt::ArgList &Args) const {
759   return CLANG_DEFAULT_PIE_ON_LINUX || getTriple().isAndroid() ||
760          getTriple().isMusl() || getSanitizerArgs(Args).requiresPIE();
761 }
762 
763 bool Linux::IsAArch64OutlineAtomicsDefault(const ArgList &Args) const {
764   // Outline atomics for AArch64 are supported by compiler-rt
765   // and libgcc since 9.3.1
766   assert(getTriple().isAArch64() && "expected AArch64 target!");
767   ToolChain::RuntimeLibType RtLib = GetRuntimeLibType(Args);
768   if (RtLib == ToolChain::RLT_CompilerRT)
769     return true;
770   assert(RtLib == ToolChain::RLT_Libgcc && "unexpected runtime library type!");
771   if (GCCInstallation.getVersion().isOlderThan(9, 3, 1))
772     return false;
773   return true;
774 }
775 
776 bool Linux::IsMathErrnoDefault() const {
777   if (getTriple().isAndroid() || getTriple().isMusl())
778     return false;
779   return Generic_ELF::IsMathErrnoDefault();
780 }
781 
782 SanitizerMask Linux::getSupportedSanitizers() const {
783   const bool IsX86 = getTriple().getArch() == llvm::Triple::x86;
784   const bool IsX86_64 = getTriple().getArch() == llvm::Triple::x86_64;
785   const bool IsMIPS = getTriple().isMIPS32();
786   const bool IsMIPS64 = getTriple().isMIPS64();
787   const bool IsPowerPC64 = getTriple().getArch() == llvm::Triple::ppc64 ||
788                            getTriple().getArch() == llvm::Triple::ppc64le;
789   const bool IsAArch64 = getTriple().getArch() == llvm::Triple::aarch64 ||
790                          getTriple().getArch() == llvm::Triple::aarch64_be;
791   const bool IsArmArch = getTriple().getArch() == llvm::Triple::arm ||
792                          getTriple().getArch() == llvm::Triple::thumb ||
793                          getTriple().getArch() == llvm::Triple::armeb ||
794                          getTriple().getArch() == llvm::Triple::thumbeb;
795   const bool IsLoongArch64 = getTriple().getArch() == llvm::Triple::loongarch64;
796   const bool IsRISCV64 = getTriple().getArch() == llvm::Triple::riscv64;
797   const bool IsSystemZ = getTriple().getArch() == llvm::Triple::systemz;
798   const bool IsHexagon = getTriple().getArch() == llvm::Triple::hexagon;
799   SanitizerMask Res = ToolChain::getSupportedSanitizers();
800   Res |= SanitizerKind::Address;
801   Res |= SanitizerKind::PointerCompare;
802   Res |= SanitizerKind::PointerSubtract;
803   Res |= SanitizerKind::Fuzzer;
804   Res |= SanitizerKind::FuzzerNoLink;
805   Res |= SanitizerKind::KernelAddress;
806   Res |= SanitizerKind::Memory;
807   Res |= SanitizerKind::Vptr;
808   Res |= SanitizerKind::SafeStack;
809   if (IsX86_64 || IsMIPS64 || IsAArch64 || IsLoongArch64)
810     Res |= SanitizerKind::DataFlow;
811   if (IsX86_64 || IsMIPS64 || IsAArch64 || IsX86 || IsArmArch || IsPowerPC64 ||
812       IsRISCV64 || IsSystemZ || IsHexagon || IsLoongArch64)
813     Res |= SanitizerKind::Leak;
814   if (IsX86_64 || IsMIPS64 || IsAArch64 || IsPowerPC64 || IsSystemZ ||
815       IsLoongArch64 || IsRISCV64)
816     Res |= SanitizerKind::Thread;
817   if (IsX86_64 || IsSystemZ || IsPowerPC64)
818     Res |= SanitizerKind::KernelMemory;
819   if (IsX86_64 || IsMIPS64 || IsAArch64 || IsX86 || IsMIPS || IsArmArch ||
820       IsPowerPC64 || IsHexagon || IsLoongArch64 || IsRISCV64)
821     Res |= SanitizerKind::Scudo;
822   if (IsX86_64 || IsAArch64 || IsRISCV64) {
823     Res |= SanitizerKind::HWAddress;
824   }
825   if (IsX86_64 || IsAArch64) {
826     Res |= SanitizerKind::KernelHWAddress;
827   }
828   if (IsX86_64)
829     Res |= SanitizerKind::NumericalStability;
830 
831   // Work around "Cannot represent a difference across sections".
832   if (getTriple().getArch() == llvm::Triple::ppc64)
833     Res &= ~SanitizerKind::Function;
834   return Res;
835 }
836 
837 void Linux::addProfileRTLibs(const llvm::opt::ArgList &Args,
838                              llvm::opt::ArgStringList &CmdArgs) const {
839   // Add linker option -u__llvm_profile_runtime to cause runtime
840   // initialization module to be linked in.
841   if (needsProfileRT(Args))
842     CmdArgs.push_back(Args.MakeArgString(
843         Twine("-u", llvm::getInstrProfRuntimeHookVarName())));
844   ToolChain::addProfileRTLibs(Args, CmdArgs);
845 }
846 
847 void Linux::addExtraOpts(llvm::opt::ArgStringList &CmdArgs) const {
848   for (const auto &Opt : ExtraOpts)
849     CmdArgs.push_back(Opt.c_str());
850 }
851 
852 const char *Linux::getDefaultLinker() const {
853   if (getTriple().isAndroid())
854     return "ld.lld";
855   return Generic_ELF::getDefaultLinker();
856 }
857