xref: /freebsd/contrib/llvm-project/clang/lib/Driver/ToolChains/Hurd.cpp (revision 7fdf597e96a02165cfe22ff357b857d5fa15ed8a)
1 //===--- Hurd.cpp - Hurd 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 "Hurd.h"
10 #include "CommonArgs.h"
11 #include "clang/Config/config.h"
12 #include "clang/Driver/Driver.h"
13 #include "clang/Driver/Options.h"
14 #include "llvm/Support/Path.h"
15 #include "llvm/Support/VirtualFileSystem.h"
16 
17 using namespace clang::driver;
18 using namespace clang::driver::toolchains;
19 using namespace clang;
20 using namespace llvm::opt;
21 
22 using tools::addPathIfExists;
23 
24 /// Get our best guess at the multiarch triple for a target.
25 ///
26 /// Debian-based systems are starting to use a multiarch setup where they use
27 /// a target-triple directory in the library and header search paths.
28 /// Unfortunately, this triple does not align with the vanilla target triple,
29 /// so we provide a rough mapping here.
30 std::string Hurd::getMultiarchTriple(const Driver &D,
31                                      const llvm::Triple &TargetTriple,
32                                      StringRef SysRoot) const {
33   switch (TargetTriple.getArch()) {
34   default:
35     break;
36 
37   case llvm::Triple::x86:
38     // We use the existence of '/lib/<triple>' as a directory to detect some
39     // common hurd triples that don't quite match the Clang triple for both
40     // 32-bit and 64-bit targets. Multiarch fixes its install triples to these
41     // regardless of what the actual target triple is.
42     if (D.getVFS().exists(SysRoot + "/lib/i386-gnu"))
43       return "i386-gnu";
44     break;
45 
46   case llvm::Triple::x86_64:
47     return "x86_64-gnu";
48   }
49 
50   // For most architectures, just use whatever we have rather than trying to be
51   // clever.
52   return TargetTriple.str();
53 }
54 
55 static StringRef getOSLibDir(const llvm::Triple &Triple, const ArgList &Args) {
56   // It happens that only x86 and PPC use the 'lib32' variant of oslibdir, and
57   // using that variant while targeting other architectures causes problems
58   // because the libraries are laid out in shared system roots that can't cope
59   // with a 'lib32' library search path being considered. So we only enable
60   // them when we know we may need it.
61   //
62   // FIXME: This is a bit of a hack. We should really unify this code for
63   // reasoning about oslibdir spellings with the lib dir spellings in the
64   // GCCInstallationDetector, but that is a more significant refactoring.
65 
66   if (Triple.getArch() == llvm::Triple::x86)
67     return "lib32";
68 
69   return Triple.isArch32Bit() ? "lib" : "lib64";
70 }
71 
72 Hurd::Hurd(const Driver &D, const llvm::Triple &Triple, const ArgList &Args)
73     : Generic_ELF(D, Triple, Args) {
74   GCCInstallation.init(Triple, Args);
75   Multilibs = GCCInstallation.getMultilibs();
76   SelectedMultilibs.assign({GCCInstallation.getMultilib()});
77   std::string SysRoot = computeSysRoot();
78   ToolChain::path_list &PPaths = getProgramPaths();
79 
80   Generic_GCC::PushPPaths(PPaths);
81 
82   // The selection of paths to try here is designed to match the patterns which
83   // the GCC driver itself uses, as this is part of the GCC-compatible driver.
84   // This was determined by running GCC in a fake filesystem, creating all
85   // possible permutations of these directories, and seeing which ones it added
86   // to the link paths.
87   path_list &Paths = getFilePaths();
88 
89   const std::string OSLibDir = std::string(getOSLibDir(Triple, Args));
90   const std::string MultiarchTriple = getMultiarchTriple(D, Triple, SysRoot);
91 
92 #ifdef ENABLE_LINKER_BUILD_ID
93   ExtraOpts.push_back("--build-id");
94 #endif
95 
96   Generic_GCC::AddMultilibPaths(D, SysRoot, OSLibDir, MultiarchTriple, Paths);
97 
98   // Similar to the logic for GCC above, if we currently running Clang inside
99   // of the requested system root, add its parent library paths to
100   // those searched.
101   // FIXME: It's not clear whether we should use the driver's installed
102   // directory ('Dir' below) or the ResourceDir.
103   if (StringRef(D.Dir).starts_with(SysRoot)) {
104     addPathIfExists(D, D.Dir + "/../lib/" + MultiarchTriple, Paths);
105     addPathIfExists(D, D.Dir + "/../" + OSLibDir, Paths);
106   }
107 
108   addPathIfExists(D, SysRoot + "/lib/" + MultiarchTriple, Paths);
109   addPathIfExists(D, SysRoot + "/lib/../" + OSLibDir, Paths);
110 
111   addPathIfExists(D, SysRoot + "/usr/lib/" + MultiarchTriple, Paths);
112   addPathIfExists(D, SysRoot + "/usr/lib/../" + OSLibDir, Paths);
113 
114   Generic_GCC::AddMultiarchPaths(D, SysRoot, OSLibDir, Paths);
115 
116   // Similar to the logic for GCC above, if we are currently running Clang
117   // inside of the requested system root, add its parent library path to those
118   // searched.
119   // FIXME: It's not clear whether we should use the driver's installed
120   // directory ('Dir' below) or the ResourceDir.
121   if (StringRef(D.Dir).starts_with(SysRoot))
122     addPathIfExists(D, D.Dir + "/../lib", Paths);
123 
124   addPathIfExists(D, SysRoot + "/lib", Paths);
125   addPathIfExists(D, SysRoot + "/usr/lib", Paths);
126 }
127 
128 bool Hurd::HasNativeLLVMSupport() const { return true; }
129 
130 Tool *Hurd::buildLinker() const { return new tools::gnutools::Linker(*this); }
131 
132 Tool *Hurd::buildAssembler() const {
133   return new tools::gnutools::Assembler(*this);
134 }
135 
136 std::string Hurd::getDynamicLinker(const ArgList &Args) const {
137   switch (getArch()) {
138   case llvm::Triple::x86:
139     return "/lib/ld.so";
140   case llvm::Triple::x86_64:
141     return "/lib/ld-x86-64.so.1";
142   default:
143     break;
144   }
145 
146   llvm_unreachable("unsupported architecture");
147 }
148 
149 void Hurd::AddClangSystemIncludeArgs(const ArgList &DriverArgs,
150                                      ArgStringList &CC1Args) const {
151   const Driver &D = getDriver();
152   std::string SysRoot = computeSysRoot();
153 
154   if (DriverArgs.hasArg(clang::driver::options::OPT_nostdinc))
155     return;
156 
157   if (!DriverArgs.hasArg(options::OPT_nostdlibinc))
158     addSystemInclude(DriverArgs, CC1Args, SysRoot + "/usr/local/include");
159 
160   if (!DriverArgs.hasArg(options::OPT_nobuiltininc)) {
161     SmallString<128> P(D.ResourceDir);
162     llvm::sys::path::append(P, "include");
163     addSystemInclude(DriverArgs, CC1Args, P);
164   }
165 
166   if (DriverArgs.hasArg(options::OPT_nostdlibinc))
167     return;
168 
169   // Check for configure-time C include directories.
170   StringRef CIncludeDirs(C_INCLUDE_DIRS);
171   if (CIncludeDirs != "") {
172     SmallVector<StringRef, 5> Dirs;
173     CIncludeDirs.split(Dirs, ":");
174     for (StringRef Dir : Dirs) {
175       StringRef Prefix =
176           llvm::sys::path::is_absolute(Dir) ? "" : StringRef(SysRoot);
177       addExternCSystemInclude(DriverArgs, CC1Args, Prefix + Dir);
178     }
179     return;
180   }
181 
182   // Lacking those, try to detect the correct set of system includes for the
183   // target triple.
184 
185   AddMultilibIncludeArgs(DriverArgs, CC1Args);
186 
187   // On systems using multiarch, add /usr/include/$triple before
188   // /usr/include.
189   std::string MultiarchIncludeDir = getMultiarchTriple(D, getTriple(), SysRoot);
190   if (!MultiarchIncludeDir.empty() &&
191       D.getVFS().exists(SysRoot + "/usr/include/" + MultiarchIncludeDir))
192     addExternCSystemInclude(DriverArgs, CC1Args,
193                             SysRoot + "/usr/include/" + MultiarchIncludeDir);
194 
195   // Add an include of '/include' directly. This isn't provided by default by
196   // system GCCs, but is often used with cross-compiling GCCs, and harmless to
197   // add even when Clang is acting as-if it were a system compiler.
198   addExternCSystemInclude(DriverArgs, CC1Args, SysRoot + "/include");
199 
200   addExternCSystemInclude(DriverArgs, CC1Args, SysRoot + "/usr/include");
201 }
202 
203 void Hurd::addLibStdCxxIncludePaths(const llvm::opt::ArgList &DriverArgs,
204                                     llvm::opt::ArgStringList &CC1Args) const {
205   // We need a detected GCC installation on Linux to provide libstdc++'s
206   // headers in odd Linuxish places.
207   if (!GCCInstallation.isValid())
208     return;
209 
210   StringRef TripleStr = GCCInstallation.getTriple().str();
211   StringRef DebianMultiarch =
212       GCCInstallation.getTriple().getArch() == llvm::Triple::x86 ? "i386-gnu"
213                                                                  : TripleStr;
214 
215   addGCCLibStdCxxIncludePaths(DriverArgs, CC1Args, DebianMultiarch);
216 }
217 
218 void Hurd::addExtraOpts(llvm::opt::ArgStringList &CmdArgs) const {
219   for (const auto &Opt : ExtraOpts)
220     CmdArgs.push_back(Opt.c_str());
221 }
222