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/Mips.h"
12 #include "Arch/PPC.h"
13 #include "Arch/RISCV.h"
14 #include "CommonArgs.h"
15 #include "clang/Config/config.h"
16 #include "clang/Driver/Distro.h"
17 #include "clang/Driver/Driver.h"
18 #include "clang/Driver/Options.h"
19 #include "clang/Driver/SanitizerArgs.h"
20 #include "llvm/Option/ArgList.h"
21 #include "llvm/ProfileData/InstrProf.h"
22 #include "llvm/Support/Path.h"
23 #include "llvm/Support/ScopedPrinter.h"
24 #include "llvm/Support/VirtualFileSystem.h"
25 #include <system_error>
26 
27 using namespace clang::driver;
28 using namespace clang::driver::toolchains;
29 using namespace clang;
30 using namespace llvm::opt;
31 
32 using tools::addPathIfExists;
33 
34 /// Get our best guess at the multiarch triple for a target.
35 ///
36 /// Debian-based systems are starting to use a multiarch setup where they use
37 /// a target-triple directory in the library and header search paths.
38 /// Unfortunately, this triple does not align with the vanilla target triple,
39 /// so we provide a rough mapping here.
getMultiarchTriple(const Driver & D,const llvm::Triple & TargetTriple,StringRef SysRoot) const40 std::string Linux::getMultiarchTriple(const Driver &D,
41                                       const llvm::Triple &TargetTriple,
42                                       StringRef SysRoot) const {
43   llvm::Triple::EnvironmentType TargetEnvironment =
44       TargetTriple.getEnvironment();
45   bool IsAndroid = TargetTriple.isAndroid();
46   bool IsMipsR6 = TargetTriple.getSubArch() == llvm::Triple::MipsSubArch_r6;
47   bool IsMipsN32Abi = TargetTriple.getEnvironment() == llvm::Triple::GNUABIN32;
48 
49   // For most architectures, just use whatever we have rather than trying to be
50   // clever.
51   switch (TargetTriple.getArch()) {
52   default:
53     break;
54 
55   // We use the existence of '/lib/<triple>' as a directory to detect some
56   // common linux triples that don't quite match the Clang triple for both
57   // 32-bit and 64-bit targets. Multiarch fixes its install triples to these
58   // regardless of what the actual target triple is.
59   case llvm::Triple::arm:
60   case llvm::Triple::thumb:
61     if (IsAndroid) {
62       return "arm-linux-androideabi";
63     } else if (TargetEnvironment == llvm::Triple::GNUEABIHF) {
64       if (D.getVFS().exists(SysRoot + "/lib/arm-linux-gnueabihf"))
65         return "arm-linux-gnueabihf";
66     } else {
67       if (D.getVFS().exists(SysRoot + "/lib/arm-linux-gnueabi"))
68         return "arm-linux-gnueabi";
69     }
70     break;
71   case llvm::Triple::armeb:
72   case llvm::Triple::thumbeb:
73     if (TargetEnvironment == llvm::Triple::GNUEABIHF) {
74       if (D.getVFS().exists(SysRoot + "/lib/armeb-linux-gnueabihf"))
75         return "armeb-linux-gnueabihf";
76     } else {
77       if (D.getVFS().exists(SysRoot + "/lib/armeb-linux-gnueabi"))
78         return "armeb-linux-gnueabi";
79     }
80     break;
81   case llvm::Triple::x86:
82     if (IsAndroid)
83       return "i686-linux-android";
84     if (D.getVFS().exists(SysRoot + "/lib/i386-linux-gnu"))
85       return "i386-linux-gnu";
86     break;
87   case llvm::Triple::x86_64:
88     if (IsAndroid)
89       return "x86_64-linux-android";
90     // We don't want this for x32, otherwise it will match x86_64 libs
91     if (TargetEnvironment != llvm::Triple::GNUX32 &&
92         D.getVFS().exists(SysRoot + "/lib/x86_64-linux-gnu"))
93       return "x86_64-linux-gnu";
94     break;
95   case llvm::Triple::aarch64:
96     if (IsAndroid)
97       return "aarch64-linux-android";
98     if (D.getVFS().exists(SysRoot + "/lib/aarch64-linux-gnu"))
99       return "aarch64-linux-gnu";
100     break;
101   case llvm::Triple::aarch64_be:
102     if (D.getVFS().exists(SysRoot + "/lib/aarch64_be-linux-gnu"))
103       return "aarch64_be-linux-gnu";
104     break;
105   case llvm::Triple::mips: {
106     std::string MT = IsMipsR6 ? "mipsisa32r6-linux-gnu" : "mips-linux-gnu";
107     if (D.getVFS().exists(SysRoot + "/lib/" + MT))
108       return MT;
109     break;
110   }
111   case llvm::Triple::mipsel: {
112     if (IsAndroid)
113       return "mipsel-linux-android";
114     std::string MT = IsMipsR6 ? "mipsisa32r6el-linux-gnu" : "mipsel-linux-gnu";
115     if (D.getVFS().exists(SysRoot + "/lib/" + MT))
116       return MT;
117     break;
118   }
119   case llvm::Triple::mips64: {
120     std::string MT = std::string(IsMipsR6 ? "mipsisa64r6" : "mips64") +
121                      "-linux-" + (IsMipsN32Abi ? "gnuabin32" : "gnuabi64");
122     if (D.getVFS().exists(SysRoot + "/lib/" + MT))
123       return MT;
124     if (D.getVFS().exists(SysRoot + "/lib/mips64-linux-gnu"))
125       return "mips64-linux-gnu";
126     break;
127   }
128   case llvm::Triple::mips64el: {
129     if (IsAndroid)
130       return "mips64el-linux-android";
131     std::string MT = std::string(IsMipsR6 ? "mipsisa64r6el" : "mips64el") +
132                      "-linux-" + (IsMipsN32Abi ? "gnuabin32" : "gnuabi64");
133     if (D.getVFS().exists(SysRoot + "/lib/" + MT))
134       return MT;
135     if (D.getVFS().exists(SysRoot + "/lib/mips64el-linux-gnu"))
136       return "mips64el-linux-gnu";
137     break;
138   }
139   case llvm::Triple::ppc:
140     if (D.getVFS().exists(SysRoot + "/lib/powerpc-linux-gnuspe"))
141       return "powerpc-linux-gnuspe";
142     if (D.getVFS().exists(SysRoot + "/lib/powerpc-linux-gnu"))
143       return "powerpc-linux-gnu";
144     break;
145   case llvm::Triple::ppcle:
146     if (D.getVFS().exists(SysRoot + "/lib/powerpcle-linux-gnu"))
147       return "powerpcle-linux-gnu";
148     break;
149   case llvm::Triple::ppc64:
150     if (D.getVFS().exists(SysRoot + "/lib/powerpc64-linux-gnu"))
151       return "powerpc64-linux-gnu";
152     break;
153   case llvm::Triple::ppc64le:
154     if (D.getVFS().exists(SysRoot + "/lib/powerpc64le-linux-gnu"))
155       return "powerpc64le-linux-gnu";
156     break;
157   case llvm::Triple::sparc:
158     if (D.getVFS().exists(SysRoot + "/lib/sparc-linux-gnu"))
159       return "sparc-linux-gnu";
160     break;
161   case llvm::Triple::sparcv9:
162     if (D.getVFS().exists(SysRoot + "/lib/sparc64-linux-gnu"))
163       return "sparc64-linux-gnu";
164     break;
165   case llvm::Triple::systemz:
166     if (D.getVFS().exists(SysRoot + "/lib/s390x-linux-gnu"))
167       return "s390x-linux-gnu";
168     break;
169   }
170   return TargetTriple.str();
171 }
172 
getOSLibDir(const llvm::Triple & Triple,const ArgList & Args)173 static StringRef getOSLibDir(const llvm::Triple &Triple, const ArgList &Args) {
174   if (Triple.isMIPS()) {
175     if (Triple.isAndroid()) {
176       StringRef CPUName;
177       StringRef ABIName;
178       tools::mips::getMipsCPUAndABI(Args, Triple, CPUName, ABIName);
179       if (CPUName == "mips32r6")
180         return "libr6";
181       if (CPUName == "mips32r2")
182         return "libr2";
183     }
184     // lib32 directory has a special meaning on MIPS targets.
185     // It contains N32 ABI binaries. Use this folder if produce
186     // code for N32 ABI only.
187     if (tools::mips::hasMipsAbiArg(Args, "n32"))
188       return "lib32";
189     return Triple.isArch32Bit() ? "lib" : "lib64";
190   }
191 
192   // It happens that only x86, PPC and SPARC use the 'lib32' variant of
193   // oslibdir, and using that variant while targeting other architectures causes
194   // problems because the libraries are laid out in shared system roots that
195   // can't cope with a 'lib32' library search path being considered. So we only
196   // enable them when we know we may need it.
197   //
198   // FIXME: This is a bit of a hack. We should really unify this code for
199   // reasoning about oslibdir spellings with the lib dir spellings in the
200   // GCCInstallationDetector, but that is a more significant refactoring.
201   if (Triple.getArch() == llvm::Triple::x86 || Triple.isPPC32() ||
202       Triple.getArch() == llvm::Triple::sparc)
203     return "lib32";
204 
205   if (Triple.getArch() == llvm::Triple::x86_64 &&
206       Triple.getEnvironment() == llvm::Triple::GNUX32)
207     return "libx32";
208 
209   if (Triple.getArch() == llvm::Triple::riscv32)
210     return "lib32";
211 
212   return Triple.isArch32Bit() ? "lib" : "lib64";
213 }
214 
Linux(const Driver & D,const llvm::Triple & Triple,const ArgList & Args)215 Linux::Linux(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
216     : Generic_ELF(D, Triple, Args) {
217   GCCInstallation.init(Triple, Args);
218   Multilibs = GCCInstallation.getMultilibs();
219   SelectedMultilib = GCCInstallation.getMultilib();
220   llvm::Triple::ArchType Arch = Triple.getArch();
221   std::string SysRoot = computeSysRoot();
222   ToolChain::path_list &PPaths = getProgramPaths();
223 
224   Generic_GCC::PushPPaths(PPaths);
225 
226   Distro Distro(D.getVFS(), Triple);
227 
228   if (Distro.IsAlpineLinux() || Triple.isAndroid()) {
229     ExtraOpts.push_back("-z");
230     ExtraOpts.push_back("now");
231   }
232 
233   if (Distro.IsOpenSUSE() || Distro.IsUbuntu() || Distro.IsAlpineLinux() ||
234       Triple.isAndroid()) {
235     ExtraOpts.push_back("-z");
236     ExtraOpts.push_back("relro");
237   }
238 
239   // Android ARM/AArch64 use max-page-size=4096 to reduce VMA usage. Note, lld
240   // from 11 onwards default max-page-size to 65536 for both ARM and AArch64.
241   if ((Triple.isARM() || Triple.isAArch64()) && Triple.isAndroid()) {
242     ExtraOpts.push_back("-z");
243     ExtraOpts.push_back("max-page-size=4096");
244   }
245 
246   if (GCCInstallation.getParentLibPath().find("opt/rh/devtoolset") !=
247       StringRef::npos)
248     // With devtoolset on RHEL, we want to add a bin directory that is relative
249     // to the detected gcc install, because if we are using devtoolset gcc then
250     // we want to use other tools from devtoolset (e.g. ld) instead of the
251     // standard system tools.
252     PPaths.push_back(Twine(GCCInstallation.getParentLibPath() +
253                      "/../bin").str());
254 
255   if (Arch == llvm::Triple::arm || Arch == llvm::Triple::thumb)
256     ExtraOpts.push_back("-X");
257 
258   const bool IsAndroid = Triple.isAndroid();
259   const bool IsMips = Triple.isMIPS();
260   const bool IsHexagon = Arch == llvm::Triple::hexagon;
261   const bool IsRISCV = Triple.isRISCV();
262 
263   if (IsMips && !SysRoot.empty())
264     ExtraOpts.push_back("--sysroot=" + SysRoot);
265 
266   // Do not use 'gnu' hash style for Mips targets because .gnu.hash
267   // and the MIPS ABI require .dynsym to be sorted in different ways.
268   // .gnu.hash needs symbols to be grouped by hash code whereas the MIPS
269   // ABI requires a mapping between the GOT and the symbol table.
270   // Android loader does not support .gnu.hash until API 23.
271   // Hexagon linker/loader does not support .gnu.hash
272   if (!IsMips && !IsHexagon) {
273     if (Distro.IsRedhat() || Distro.IsOpenSUSE() || Distro.IsAlpineLinux() ||
274         (Distro.IsUbuntu() && Distro >= Distro::UbuntuMaverick) ||
275         (IsAndroid && !Triple.isAndroidVersionLT(23)))
276       ExtraOpts.push_back("--hash-style=gnu");
277 
278     if (Distro.IsDebian() || Distro.IsOpenSUSE() ||
279         Distro == Distro::UbuntuLucid || Distro == Distro::UbuntuJaunty ||
280         Distro == Distro::UbuntuKarmic ||
281         (IsAndroid && Triple.isAndroidVersionLT(23)))
282       ExtraOpts.push_back("--hash-style=both");
283   }
284 
285 #ifdef ENABLE_LINKER_BUILD_ID
286   ExtraOpts.push_back("--build-id");
287 #endif
288 
289   if (IsAndroid || Distro.IsOpenSUSE())
290     ExtraOpts.push_back("--enable-new-dtags");
291 
292   // The selection of paths to try here is designed to match the patterns which
293   // the GCC driver itself uses, as this is part of the GCC-compatible driver.
294   // This was determined by running GCC in a fake filesystem, creating all
295   // possible permutations of these directories, and seeing which ones it added
296   // to the link paths.
297   path_list &Paths = getFilePaths();
298 
299   const std::string OSLibDir = std::string(getOSLibDir(Triple, Args));
300   const std::string MultiarchTriple = getMultiarchTriple(D, Triple, SysRoot);
301 
302   Generic_GCC::AddMultilibPaths(D, SysRoot, OSLibDir, MultiarchTriple, Paths);
303 
304   // Similar to the logic for GCC above, if we currently running Clang inside
305   // of the requested system root, add its parent library paths to
306   // those searched.
307   // FIXME: It's not clear whether we should use the driver's installed
308   // directory ('Dir' below) or the ResourceDir.
309   if (StringRef(D.Dir).startswith(SysRoot)) {
310     addPathIfExists(D, D.Dir + "/../lib/" + MultiarchTriple, Paths);
311     addPathIfExists(D, D.Dir + "/../" + OSLibDir, Paths);
312   }
313 
314   addPathIfExists(D, SysRoot + "/lib/" + MultiarchTriple, Paths);
315   addPathIfExists(D, SysRoot + "/lib/../" + OSLibDir, Paths);
316 
317   if (IsAndroid) {
318     // Android sysroots contain a library directory for each supported OS
319     // version as well as some unversioned libraries in the usual multiarch
320     // directory.
321     unsigned Major;
322     unsigned Minor;
323     unsigned Micro;
324     Triple.getEnvironmentVersion(Major, Minor, Micro);
325     addPathIfExists(D,
326                     SysRoot + "/usr/lib/" + MultiarchTriple + "/" +
327                         llvm::to_string(Major),
328                     Paths);
329   }
330 
331   addPathIfExists(D, SysRoot + "/usr/lib/" + MultiarchTriple, Paths);
332   // 64-bit OpenEmbedded sysroots may not have a /usr/lib dir. So they cannot
333   // find /usr/lib64 as it is referenced as /usr/lib/../lib64. So we handle
334   // this here.
335   if (Triple.getVendor() == llvm::Triple::OpenEmbedded &&
336       Triple.isArch64Bit())
337     addPathIfExists(D, SysRoot + "/usr/" + OSLibDir, Paths);
338   else
339     addPathIfExists(D, SysRoot + "/usr/lib/../" + OSLibDir, Paths);
340   if (IsRISCV) {
341     StringRef ABIName = tools::riscv::getRISCVABI(Args, Triple);
342     addPathIfExists(D, SysRoot + "/" + OSLibDir + "/" + ABIName, Paths);
343     addPathIfExists(D, SysRoot + "/usr/" + OSLibDir + "/" + ABIName, Paths);
344   }
345 
346   Generic_GCC::AddMultiarchPaths(D, SysRoot, OSLibDir, Paths);
347 
348   // Similar to the logic for GCC above, if we are currently running Clang
349   // inside of the requested system root, add its parent library path to those
350   // searched.
351   // FIXME: It's not clear whether we should use the driver's installed
352   // directory ('Dir' below) or the ResourceDir.
353   if (StringRef(D.Dir).startswith(SysRoot))
354     addPathIfExists(D, D.Dir + "/../lib", Paths);
355 
356   addPathIfExists(D, SysRoot + "/lib", Paths);
357   addPathIfExists(D, SysRoot + "/usr/lib", Paths);
358 }
359 
GetDefaultCXXStdlibType() const360 ToolChain::CXXStdlibType Linux::GetDefaultCXXStdlibType() const {
361   if (getTriple().isAndroid())
362     return ToolChain::CST_Libcxx;
363   return ToolChain::CST_Libstdcxx;
364 }
365 
HasNativeLLVMSupport() const366 bool Linux::HasNativeLLVMSupport() const { return true; }
367 
buildLinker() const368 Tool *Linux::buildLinker() const { return new tools::gnutools::Linker(*this); }
369 
buildStaticLibTool() const370 Tool *Linux::buildStaticLibTool() const {
371   return new tools::gnutools::StaticLibTool(*this);
372 }
373 
buildAssembler() const374 Tool *Linux::buildAssembler() const {
375   return new tools::gnutools::Assembler(*this);
376 }
377 
computeSysRoot() const378 std::string Linux::computeSysRoot() const {
379   if (!getDriver().SysRoot.empty())
380     return getDriver().SysRoot;
381 
382   if (getTriple().isAndroid()) {
383     // Android toolchains typically include a sysroot at ../sysroot relative to
384     // the clang binary.
385     const StringRef ClangDir = getDriver().getInstalledDir();
386     std::string AndroidSysRootPath = (ClangDir + "/../sysroot").str();
387     if (getVFS().exists(AndroidSysRootPath))
388       return AndroidSysRootPath;
389   }
390 
391   if (!GCCInstallation.isValid() || !getTriple().isMIPS())
392     return std::string();
393 
394   // Standalone MIPS toolchains use different names for sysroot folder
395   // and put it into different places. Here we try to check some known
396   // variants.
397 
398   const StringRef InstallDir = GCCInstallation.getInstallPath();
399   const StringRef TripleStr = GCCInstallation.getTriple().str();
400   const Multilib &Multilib = GCCInstallation.getMultilib();
401 
402   std::string Path =
403       (InstallDir + "/../../../../" + TripleStr + "/libc" + Multilib.osSuffix())
404           .str();
405 
406   if (getVFS().exists(Path))
407     return Path;
408 
409   Path = (InstallDir + "/../../../../sysroot" + Multilib.osSuffix()).str();
410 
411   if (getVFS().exists(Path))
412     return Path;
413 
414   return std::string();
415 }
416 
getDynamicLinker(const ArgList & Args) const417 std::string Linux::getDynamicLinker(const ArgList &Args) const {
418   const llvm::Triple::ArchType Arch = getArch();
419   const llvm::Triple &Triple = getTriple();
420 
421   const Distro Distro(getDriver().getVFS(), Triple);
422 
423   if (Triple.isAndroid())
424     return Triple.isArch64Bit() ? "/system/bin/linker64" : "/system/bin/linker";
425 
426   if (Triple.isMusl()) {
427     std::string ArchName;
428     bool IsArm = false;
429 
430     switch (Arch) {
431     case llvm::Triple::arm:
432     case llvm::Triple::thumb:
433       ArchName = "arm";
434       IsArm = true;
435       break;
436     case llvm::Triple::armeb:
437     case llvm::Triple::thumbeb:
438       ArchName = "armeb";
439       IsArm = true;
440       break;
441     default:
442       ArchName = Triple.getArchName().str();
443     }
444     if (IsArm &&
445         (Triple.getEnvironment() == llvm::Triple::MuslEABIHF ||
446          tools::arm::getARMFloatABI(*this, Args) == tools::arm::FloatABI::Hard))
447       ArchName += "hf";
448 
449     return "/lib/ld-musl-" + ArchName + ".so.1";
450   }
451 
452   std::string LibDir;
453   std::string Loader;
454 
455   switch (Arch) {
456   default:
457     llvm_unreachable("unsupported architecture");
458 
459   case llvm::Triple::aarch64:
460     LibDir = "lib";
461     Loader = "ld-linux-aarch64.so.1";
462     break;
463   case llvm::Triple::aarch64_be:
464     LibDir = "lib";
465     Loader = "ld-linux-aarch64_be.so.1";
466     break;
467   case llvm::Triple::arm:
468   case llvm::Triple::thumb:
469   case llvm::Triple::armeb:
470   case llvm::Triple::thumbeb: {
471     const bool HF =
472         Triple.getEnvironment() == llvm::Triple::GNUEABIHF ||
473         tools::arm::getARMFloatABI(*this, Args) == tools::arm::FloatABI::Hard;
474 
475     LibDir = "lib";
476     Loader = HF ? "ld-linux-armhf.so.3" : "ld-linux.so.3";
477     break;
478   }
479   case llvm::Triple::mips:
480   case llvm::Triple::mipsel:
481   case llvm::Triple::mips64:
482   case llvm::Triple::mips64el: {
483     bool IsNaN2008 = tools::mips::isNaN2008(Args, Triple);
484 
485     LibDir = "lib" + tools::mips::getMipsABILibSuffix(Args, Triple);
486 
487     if (tools::mips::isUCLibc(Args))
488       Loader = IsNaN2008 ? "ld-uClibc-mipsn8.so.0" : "ld-uClibc.so.0";
489     else if (!Triple.hasEnvironment() &&
490              Triple.getVendor() == llvm::Triple::VendorType::MipsTechnologies)
491       Loader =
492           Triple.isLittleEndian() ? "ld-musl-mipsel.so.1" : "ld-musl-mips.so.1";
493     else
494       Loader = IsNaN2008 ? "ld-linux-mipsn8.so.1" : "ld.so.1";
495 
496     break;
497   }
498   case llvm::Triple::ppc:
499     LibDir = "lib";
500     Loader = "ld.so.1";
501     break;
502   case llvm::Triple::ppcle:
503     LibDir = "lib";
504     Loader = "ld.so.1";
505     break;
506   case llvm::Triple::ppc64:
507     LibDir = "lib64";
508     Loader =
509         (tools::ppc::hasPPCAbiArg(Args, "elfv2")) ? "ld64.so.2" : "ld64.so.1";
510     break;
511   case llvm::Triple::ppc64le:
512     LibDir = "lib64";
513     Loader =
514         (tools::ppc::hasPPCAbiArg(Args, "elfv1")) ? "ld64.so.1" : "ld64.so.2";
515     break;
516   case llvm::Triple::riscv32: {
517     StringRef ABIName = tools::riscv::getRISCVABI(Args, Triple);
518     LibDir = "lib";
519     Loader = ("ld-linux-riscv32-" + ABIName + ".so.1").str();
520     break;
521   }
522   case llvm::Triple::riscv64: {
523     StringRef ABIName = tools::riscv::getRISCVABI(Args, Triple);
524     LibDir = "lib";
525     Loader = ("ld-linux-riscv64-" + ABIName + ".so.1").str();
526     break;
527   }
528   case llvm::Triple::sparc:
529   case llvm::Triple::sparcel:
530     LibDir = "lib";
531     Loader = "ld-linux.so.2";
532     break;
533   case llvm::Triple::sparcv9:
534     LibDir = "lib64";
535     Loader = "ld-linux.so.2";
536     break;
537   case llvm::Triple::systemz:
538     LibDir = "lib";
539     Loader = "ld64.so.1";
540     break;
541   case llvm::Triple::x86:
542     LibDir = "lib";
543     Loader = "ld-linux.so.2";
544     break;
545   case llvm::Triple::x86_64: {
546     bool X32 = Triple.getEnvironment() == llvm::Triple::GNUX32;
547 
548     LibDir = X32 ? "libx32" : "lib64";
549     Loader = X32 ? "ld-linux-x32.so.2" : "ld-linux-x86-64.so.2";
550     break;
551   }
552   case llvm::Triple::ve:
553     return "/opt/nec/ve/lib/ld-linux-ve.so.1";
554   }
555 
556   if (Distro == Distro::Exherbo &&
557       (Triple.getVendor() == llvm::Triple::UnknownVendor ||
558        Triple.getVendor() == llvm::Triple::PC))
559     return "/usr/" + Triple.str() + "/lib/" + Loader;
560   return "/" + LibDir + "/" + Loader;
561 }
562 
AddClangSystemIncludeArgs(const ArgList & DriverArgs,ArgStringList & CC1Args) const563 void Linux::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
564                                       ArgStringList &CC1Args) const {
565   const Driver &D = getDriver();
566   std::string SysRoot = computeSysRoot();
567 
568   if (DriverArgs.hasArg(clang::driver::options::OPT_nostdinc))
569     return;
570 
571   if (!DriverArgs.hasArg(options::OPT_nostdlibinc))
572     addSystemInclude(DriverArgs, CC1Args, SysRoot + "/usr/local/include");
573 
574   SmallString<128> ResourceDirInclude(D.ResourceDir);
575   llvm::sys::path::append(ResourceDirInclude, "include");
576   if (!DriverArgs.hasArg(options::OPT_nobuiltininc) &&
577       (!getTriple().isMusl() || DriverArgs.hasArg(options::OPT_nostdlibinc)))
578     addSystemInclude(DriverArgs, CC1Args, ResourceDirInclude);
579 
580   if (DriverArgs.hasArg(options::OPT_nostdlibinc))
581     return;
582 
583   // Check for configure-time C include directories.
584   StringRef CIncludeDirs(C_INCLUDE_DIRS);
585   if (CIncludeDirs != "") {
586     SmallVector<StringRef, 5> dirs;
587     CIncludeDirs.split(dirs, ":");
588     for (StringRef dir : dirs) {
589       StringRef Prefix =
590           llvm::sys::path::is_absolute(dir) ? "" : StringRef(SysRoot);
591       addExternCSystemInclude(DriverArgs, CC1Args, Prefix + dir);
592     }
593     return;
594   }
595 
596   // Lacking those, try to detect the correct set of system includes for the
597   // target triple.
598 
599   AddMultilibIncludeArgs(DriverArgs, CC1Args);
600 
601   // Implement generic Debian multiarch support.
602   const StringRef X86_64MultiarchIncludeDirs[] = {
603       "/usr/include/x86_64-linux-gnu",
604 
605       // FIXME: These are older forms of multiarch. It's not clear that they're
606       // in use in any released version of Debian, so we should consider
607       // removing them.
608       "/usr/include/i686-linux-gnu/64", "/usr/include/i486-linux-gnu/64"};
609   const StringRef X86MultiarchIncludeDirs[] = {
610       "/usr/include/i386-linux-gnu",
611 
612       // FIXME: These are older forms of multiarch. It's not clear that they're
613       // in use in any released version of Debian, so we should consider
614       // removing them.
615       "/usr/include/x86_64-linux-gnu/32", "/usr/include/i686-linux-gnu",
616       "/usr/include/i486-linux-gnu"};
617   const StringRef AArch64MultiarchIncludeDirs[] = {
618       "/usr/include/aarch64-linux-gnu"};
619   const StringRef ARMMultiarchIncludeDirs[] = {
620       "/usr/include/arm-linux-gnueabi"};
621   const StringRef ARMHFMultiarchIncludeDirs[] = {
622       "/usr/include/arm-linux-gnueabihf"};
623   const StringRef ARMEBMultiarchIncludeDirs[] = {
624       "/usr/include/armeb-linux-gnueabi"};
625   const StringRef ARMEBHFMultiarchIncludeDirs[] = {
626       "/usr/include/armeb-linux-gnueabihf"};
627   const StringRef MIPSMultiarchIncludeDirs[] = {"/usr/include/mips-linux-gnu"};
628   const StringRef MIPSELMultiarchIncludeDirs[] = {
629       "/usr/include/mipsel-linux-gnu"};
630   const StringRef MIPS64MultiarchIncludeDirs[] = {
631       "/usr/include/mips64-linux-gnuabi64"};
632   const StringRef MIPS64ELMultiarchIncludeDirs[] = {
633       "/usr/include/mips64el-linux-gnuabi64"};
634   const StringRef MIPSN32MultiarchIncludeDirs[] = {
635       "/usr/include/mips64-linux-gnuabin32"};
636   const StringRef MIPSN32ELMultiarchIncludeDirs[] = {
637       "/usr/include/mips64el-linux-gnuabin32"};
638   const StringRef MIPSR6MultiarchIncludeDirs[] = {
639       "/usr/include/mipsisa32-linux-gnu"};
640   const StringRef MIPSR6ELMultiarchIncludeDirs[] = {
641       "/usr/include/mipsisa32r6el-linux-gnu"};
642   const StringRef MIPS64R6MultiarchIncludeDirs[] = {
643       "/usr/include/mipsisa64r6-linux-gnuabi64"};
644   const StringRef MIPS64R6ELMultiarchIncludeDirs[] = {
645       "/usr/include/mipsisa64r6el-linux-gnuabi64"};
646   const StringRef MIPSN32R6MultiarchIncludeDirs[] = {
647       "/usr/include/mipsisa64r6-linux-gnuabin32"};
648   const StringRef MIPSN32R6ELMultiarchIncludeDirs[] = {
649       "/usr/include/mipsisa64r6el-linux-gnuabin32"};
650   const StringRef PPCMultiarchIncludeDirs[] = {
651       "/usr/include/powerpc-linux-gnu",
652       "/usr/include/powerpc-linux-gnuspe"};
653   const StringRef PPCLEMultiarchIncludeDirs[] = {
654       "/usr/include/powerpcle-linux-gnu"};
655   const StringRef PPC64MultiarchIncludeDirs[] = {
656       "/usr/include/powerpc64-linux-gnu"};
657   const StringRef PPC64LEMultiarchIncludeDirs[] = {
658       "/usr/include/powerpc64le-linux-gnu"};
659   const StringRef SparcMultiarchIncludeDirs[] = {
660       "/usr/include/sparc-linux-gnu"};
661   const StringRef Sparc64MultiarchIncludeDirs[] = {
662       "/usr/include/sparc64-linux-gnu"};
663   const StringRef SYSTEMZMultiarchIncludeDirs[] = {
664       "/usr/include/s390x-linux-gnu"};
665   ArrayRef<StringRef> MultiarchIncludeDirs;
666   switch (getTriple().getArch()) {
667   case llvm::Triple::x86_64:
668     MultiarchIncludeDirs = X86_64MultiarchIncludeDirs;
669     break;
670   case llvm::Triple::x86:
671     MultiarchIncludeDirs = X86MultiarchIncludeDirs;
672     break;
673   case llvm::Triple::aarch64:
674   case llvm::Triple::aarch64_be:
675     MultiarchIncludeDirs = AArch64MultiarchIncludeDirs;
676     break;
677   case llvm::Triple::arm:
678   case llvm::Triple::thumb:
679     if (getTriple().getEnvironment() == llvm::Triple::GNUEABIHF)
680       MultiarchIncludeDirs = ARMHFMultiarchIncludeDirs;
681     else
682       MultiarchIncludeDirs = ARMMultiarchIncludeDirs;
683     break;
684   case llvm::Triple::armeb:
685   case llvm::Triple::thumbeb:
686     if (getTriple().getEnvironment() == llvm::Triple::GNUEABIHF)
687       MultiarchIncludeDirs = ARMEBHFMultiarchIncludeDirs;
688     else
689       MultiarchIncludeDirs = ARMEBMultiarchIncludeDirs;
690     break;
691   case llvm::Triple::mips:
692     if (getTriple().getSubArch() == llvm::Triple::MipsSubArch_r6)
693       MultiarchIncludeDirs = MIPSR6MultiarchIncludeDirs;
694     else
695       MultiarchIncludeDirs = MIPSMultiarchIncludeDirs;
696     break;
697   case llvm::Triple::mipsel:
698     if (getTriple().getSubArch() == llvm::Triple::MipsSubArch_r6)
699       MultiarchIncludeDirs = MIPSR6ELMultiarchIncludeDirs;
700     else
701       MultiarchIncludeDirs = MIPSELMultiarchIncludeDirs;
702     break;
703   case llvm::Triple::mips64:
704     if (getTriple().getSubArch() == llvm::Triple::MipsSubArch_r6)
705       if (getTriple().getEnvironment() == llvm::Triple::GNUABIN32)
706         MultiarchIncludeDirs = MIPSN32R6MultiarchIncludeDirs;
707       else
708         MultiarchIncludeDirs = MIPS64R6MultiarchIncludeDirs;
709     else if (getTriple().getEnvironment() == llvm::Triple::GNUABIN32)
710       MultiarchIncludeDirs = MIPSN32MultiarchIncludeDirs;
711     else
712       MultiarchIncludeDirs = MIPS64MultiarchIncludeDirs;
713     break;
714   case llvm::Triple::mips64el:
715     if (getTriple().getSubArch() == llvm::Triple::MipsSubArch_r6)
716       if (getTriple().getEnvironment() == llvm::Triple::GNUABIN32)
717         MultiarchIncludeDirs = MIPSN32R6ELMultiarchIncludeDirs;
718       else
719         MultiarchIncludeDirs = MIPS64R6ELMultiarchIncludeDirs;
720     else if (getTriple().getEnvironment() == llvm::Triple::GNUABIN32)
721       MultiarchIncludeDirs = MIPSN32ELMultiarchIncludeDirs;
722     else
723       MultiarchIncludeDirs = MIPS64ELMultiarchIncludeDirs;
724     break;
725   case llvm::Triple::ppc:
726     MultiarchIncludeDirs = PPCMultiarchIncludeDirs;
727     break;
728   case llvm::Triple::ppcle:
729     MultiarchIncludeDirs = PPCLEMultiarchIncludeDirs;
730     break;
731   case llvm::Triple::ppc64:
732     MultiarchIncludeDirs = PPC64MultiarchIncludeDirs;
733     break;
734   case llvm::Triple::ppc64le:
735     MultiarchIncludeDirs = PPC64LEMultiarchIncludeDirs;
736     break;
737   case llvm::Triple::sparc:
738     MultiarchIncludeDirs = SparcMultiarchIncludeDirs;
739     break;
740   case llvm::Triple::sparcv9:
741     MultiarchIncludeDirs = Sparc64MultiarchIncludeDirs;
742     break;
743   case llvm::Triple::systemz:
744     MultiarchIncludeDirs = SYSTEMZMultiarchIncludeDirs;
745     break;
746   default:
747     break;
748   }
749 
750   const std::string AndroidMultiarchIncludeDir =
751       std::string("/usr/include/") +
752       getMultiarchTriple(D, getTriple(), SysRoot);
753   const StringRef AndroidMultiarchIncludeDirs[] = {AndroidMultiarchIncludeDir};
754   if (getTriple().isAndroid())
755     MultiarchIncludeDirs = AndroidMultiarchIncludeDirs;
756 
757   for (StringRef Dir : MultiarchIncludeDirs) {
758     if (D.getVFS().exists(SysRoot + Dir)) {
759       addExternCSystemInclude(DriverArgs, CC1Args, SysRoot + Dir);
760       break;
761     }
762   }
763 
764   if (getTriple().getOS() == llvm::Triple::RTEMS)
765     return;
766 
767   // Add an include of '/include' directly. This isn't provided by default by
768   // system GCCs, but is often used with cross-compiling GCCs, and harmless to
769   // add even when Clang is acting as-if it were a system compiler.
770   addExternCSystemInclude(DriverArgs, CC1Args, SysRoot + "/include");
771 
772   addExternCSystemInclude(DriverArgs, CC1Args, SysRoot + "/usr/include");
773 
774   if (!DriverArgs.hasArg(options::OPT_nobuiltininc) && getTriple().isMusl())
775     addSystemInclude(DriverArgs, CC1Args, ResourceDirInclude);
776 }
777 
addLibStdCxxIncludePaths(const llvm::opt::ArgList & DriverArgs,llvm::opt::ArgStringList & CC1Args) const778 void Linux::addLibStdCxxIncludePaths(const llvm::opt::ArgList &DriverArgs,
779                                      llvm::opt::ArgStringList &CC1Args) const {
780   // Try generic GCC detection first.
781   if (Generic_GCC::addGCCLibStdCxxIncludePaths(DriverArgs, CC1Args))
782     return;
783 
784   // We need a detected GCC installation on Linux to provide libstdc++'s
785   // headers in odd Linuxish places.
786   if (!GCCInstallation.isValid())
787     return;
788 
789   StringRef LibDir = GCCInstallation.getParentLibPath();
790   StringRef TripleStr = GCCInstallation.getTriple().str();
791   const Multilib &Multilib = GCCInstallation.getMultilib();
792   const GCCVersion &Version = GCCInstallation.getVersion();
793 
794   const std::string LibStdCXXIncludePathCandidates[] = {
795       // Android standalone toolchain has C++ headers in yet another place.
796       LibDir.str() + "/../" + TripleStr.str() + "/include/c++/" + Version.Text,
797       // Freescale SDK C++ headers are directly in <sysroot>/usr/include/c++,
798       // without a subdirectory corresponding to the gcc version.
799       LibDir.str() + "/../include/c++",
800       // Cray's gcc installation puts headers under "g++" without a
801       // version suffix.
802       LibDir.str() + "/../include/g++",
803   };
804 
805   for (const auto &IncludePath : LibStdCXXIncludePathCandidates) {
806     if (addLibStdCXXIncludePaths(IncludePath, /*Suffix*/ "", TripleStr,
807                                  /*GCCMultiarchTriple*/ "",
808                                  /*TargetMultiarchTriple*/ "",
809                                  Multilib.includeSuffix(), DriverArgs, CC1Args))
810       break;
811   }
812 }
813 
AddCudaIncludeArgs(const ArgList & DriverArgs,ArgStringList & CC1Args) const814 void Linux::AddCudaIncludeArgs(const ArgList &DriverArgs,
815                                ArgStringList &CC1Args) const {
816   CudaInstallation.AddCudaIncludeArgs(DriverArgs, CC1Args);
817 }
818 
AddHIPIncludeArgs(const ArgList & DriverArgs,ArgStringList & CC1Args) const819 void Linux::AddHIPIncludeArgs(const ArgList &DriverArgs,
820                               ArgStringList &CC1Args) const {
821   RocmInstallation.AddHIPIncludeArgs(DriverArgs, CC1Args);
822 }
823 
AddIAMCUIncludeArgs(const ArgList & DriverArgs,ArgStringList & CC1Args) const824 void Linux::AddIAMCUIncludeArgs(const ArgList &DriverArgs,
825                                 ArgStringList &CC1Args) const {
826   if (GCCInstallation.isValid()) {
827     CC1Args.push_back("-isystem");
828     CC1Args.push_back(DriverArgs.MakeArgString(
829         GCCInstallation.getParentLibPath() + "/../" +
830         GCCInstallation.getTriple().str() + "/include"));
831   }
832 }
833 
isPIEDefault() const834 bool Linux::isPIEDefault() const {
835   return (getTriple().isAndroid() && !getTriple().isAndroidVersionLT(16)) ||
836           getTriple().isMusl() || getSanitizerArgs().requiresPIE();
837 }
838 
isNoExecStackDefault() const839 bool Linux::isNoExecStackDefault() const {
840     return getTriple().isAndroid();
841 }
842 
IsMathErrnoDefault() const843 bool Linux::IsMathErrnoDefault() const {
844   if (getTriple().isAndroid())
845     return false;
846   return Generic_ELF::IsMathErrnoDefault();
847 }
848 
getSupportedSanitizers() const849 SanitizerMask Linux::getSupportedSanitizers() const {
850   const bool IsX86 = getTriple().getArch() == llvm::Triple::x86;
851   const bool IsX86_64 = getTriple().getArch() == llvm::Triple::x86_64;
852   const bool IsMIPS = getTriple().isMIPS32();
853   const bool IsMIPS64 = getTriple().isMIPS64();
854   const bool IsPowerPC64 = getTriple().getArch() == llvm::Triple::ppc64 ||
855                            getTriple().getArch() == llvm::Triple::ppc64le;
856   const bool IsAArch64 = getTriple().getArch() == llvm::Triple::aarch64 ||
857                          getTriple().getArch() == llvm::Triple::aarch64_be;
858   const bool IsArmArch = getTriple().getArch() == llvm::Triple::arm ||
859                          getTriple().getArch() == llvm::Triple::thumb ||
860                          getTriple().getArch() == llvm::Triple::armeb ||
861                          getTriple().getArch() == llvm::Triple::thumbeb;
862   const bool IsSystemZ = getTriple().getArch() == llvm::Triple::systemz;
863   SanitizerMask Res = ToolChain::getSupportedSanitizers();
864   Res |= SanitizerKind::Address;
865   Res |= SanitizerKind::PointerCompare;
866   Res |= SanitizerKind::PointerSubtract;
867   Res |= SanitizerKind::Fuzzer;
868   Res |= SanitizerKind::FuzzerNoLink;
869   Res |= SanitizerKind::KernelAddress;
870   Res |= SanitizerKind::Memory;
871   Res |= SanitizerKind::Vptr;
872   Res |= SanitizerKind::SafeStack;
873   if (IsX86_64 || IsMIPS64 || IsAArch64)
874     Res |= SanitizerKind::DataFlow;
875   if (IsX86_64 || IsMIPS64 || IsAArch64 || IsX86 || IsArmArch || IsPowerPC64 ||
876       IsSystemZ)
877     Res |= SanitizerKind::Leak;
878   if (IsX86_64 || IsMIPS64 || IsAArch64 || IsPowerPC64)
879     Res |= SanitizerKind::Thread;
880   if (IsX86_64)
881     Res |= SanitizerKind::KernelMemory;
882   if (IsX86 || IsX86_64)
883     Res |= SanitizerKind::Function;
884   if (IsX86_64 || IsMIPS64 || IsAArch64 || IsX86 || IsMIPS || IsArmArch ||
885       IsPowerPC64)
886     Res |= SanitizerKind::Scudo;
887   if (IsX86_64 || IsAArch64) {
888     Res |= SanitizerKind::HWAddress;
889     Res |= SanitizerKind::KernelHWAddress;
890   }
891   return Res;
892 }
893 
addProfileRTLibs(const llvm::opt::ArgList & Args,llvm::opt::ArgStringList & CmdArgs) const894 void Linux::addProfileRTLibs(const llvm::opt::ArgList &Args,
895                              llvm::opt::ArgStringList &CmdArgs) const {
896   // Add linker option -u__llvm_profile_runtime to cause runtime
897   // initialization module to be linked in.
898   if (needsProfileRT(Args))
899     CmdArgs.push_back(Args.MakeArgString(
900         Twine("-u", llvm::getInstrProfRuntimeHookVarName())));
901   ToolChain::addProfileRTLibs(Args, CmdArgs);
902 }
903 
904 llvm::DenormalMode
getDefaultDenormalModeForType(const llvm::opt::ArgList & DriverArgs,const JobAction & JA,const llvm::fltSemantics * FPType) const905 Linux::getDefaultDenormalModeForType(const llvm::opt::ArgList &DriverArgs,
906                                      const JobAction &JA,
907                                      const llvm::fltSemantics *FPType) const {
908   switch (getTriple().getArch()) {
909   case llvm::Triple::x86:
910   case llvm::Triple::x86_64: {
911     std::string Unused;
912     // DAZ and FTZ are turned on in crtfastmath.o
913     if (!DriverArgs.hasArg(options::OPT_nostdlib, options::OPT_nostartfiles) &&
914         isFastMathRuntimeAvailable(DriverArgs, Unused))
915       return llvm::DenormalMode::getPreserveSign();
916     return llvm::DenormalMode::getIEEE();
917   }
918   default:
919     return llvm::DenormalMode::getIEEE();
920   }
921 }
922 
addExtraOpts(llvm::opt::ArgStringList & CmdArgs) const923 void Linux::addExtraOpts(llvm::opt::ArgStringList &CmdArgs) const {
924   for (const auto &Opt : ExtraOpts)
925     CmdArgs.push_back(Opt.c_str());
926 }
927