1 //===--- Tooling.cpp - Running clang standalone tools ---------------------===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 //  This file implements functions to run clang tools standalone instead
11 //  of running them as a plugin.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "clang/Tooling/Tooling.h"
16 #include "clang/Driver/Compilation.h"
17 #include "clang/Driver/Driver.h"
18 #include "clang/Driver/Options.h"
19 #include "clang/Driver/Tool.h"
20 #include "clang/Driver/ToolChain.h"
21 #include "clang/Frontend/ASTUnit.h"
22 #include "clang/Frontend/CompilerInstance.h"
23 #include "clang/Frontend/FrontendDiagnostic.h"
24 #include "clang/Frontend/TextDiagnosticPrinter.h"
25 #include "clang/Lex/PreprocessorOptions.h"
26 #include "clang/Tooling/ArgumentsAdjusters.h"
27 #include "clang/Tooling/CompilationDatabase.h"
28 #include "llvm/ADT/STLExtras.h"
29 #include "llvm/Config/llvm-config.h"
30 #include "llvm/Option/ArgList.h"
31 #include "llvm/Option/Option.h"
32 #include "llvm/Support/Debug.h"
33 #include "llvm/Support/FileSystem.h"
34 #include "llvm/Support/Host.h"
35 #include "llvm/Support/Path.h"
36 #include "llvm/Support/raw_ostream.h"
37 #include <utility>
38 
39 #define DEBUG_TYPE "clang-tooling"
40 
41 namespace clang {
42 namespace tooling {
43 
44 ToolAction::~ToolAction() {}
45 
46 FrontendActionFactory::~FrontendActionFactory() {}
47 
48 // FIXME: This file contains structural duplication with other parts of the
49 // code that sets up a compiler to run tools on it, and we should refactor
50 // it to be based on the same framework.
51 
52 /// \brief Builds a clang driver initialized for running clang tools.
53 static clang::driver::Driver *newDriver(
54     clang::DiagnosticsEngine *Diagnostics, const char *BinaryName,
55     IntrusiveRefCntPtr<vfs::FileSystem> VFS) {
56   clang::driver::Driver *CompilerDriver =
57       new clang::driver::Driver(BinaryName, llvm::sys::getDefaultTargetTriple(),
58                                 *Diagnostics, std::move(VFS));
59   CompilerDriver->setTitle("clang_based_tool");
60   return CompilerDriver;
61 }
62 
63 /// \brief Retrieves the clang CC1 specific flags out of the compilation's jobs.
64 ///
65 /// Returns NULL on error.
66 static const llvm::opt::ArgStringList *getCC1Arguments(
67     clang::DiagnosticsEngine *Diagnostics,
68     clang::driver::Compilation *Compilation) {
69   // We expect to get back exactly one Command job, if we didn't something
70   // failed. Extract that job from the Compilation.
71   const clang::driver::JobList &Jobs = Compilation->getJobs();
72   if (Jobs.size() != 1 || !isa<clang::driver::Command>(*Jobs.begin())) {
73     SmallString<256> error_msg;
74     llvm::raw_svector_ostream error_stream(error_msg);
75     Jobs.Print(error_stream, "; ", true);
76     Diagnostics->Report(clang::diag::err_fe_expected_compiler_job)
77         << error_stream.str();
78     return nullptr;
79   }
80 
81   // The one job we find should be to invoke clang again.
82   const clang::driver::Command &Cmd =
83       cast<clang::driver::Command>(*Jobs.begin());
84   if (StringRef(Cmd.getCreator().getName()) != "clang") {
85     Diagnostics->Report(clang::diag::err_fe_expected_clang_command);
86     return nullptr;
87   }
88 
89   return &Cmd.getArguments();
90 }
91 
92 /// \brief Returns a clang build invocation initialized from the CC1 flags.
93 clang::CompilerInvocation *newInvocation(
94     clang::DiagnosticsEngine *Diagnostics,
95     const llvm::opt::ArgStringList &CC1Args) {
96   assert(!CC1Args.empty() && "Must at least contain the program name!");
97   clang::CompilerInvocation *Invocation = new clang::CompilerInvocation;
98   clang::CompilerInvocation::CreateFromArgs(
99       *Invocation, CC1Args.data() + 1, CC1Args.data() + CC1Args.size(),
100       *Diagnostics);
101   Invocation->getFrontendOpts().DisableFree = false;
102   Invocation->getCodeGenOpts().DisableFree = false;
103   Invocation->getDependencyOutputOpts() = DependencyOutputOptions();
104   return Invocation;
105 }
106 
107 bool runToolOnCode(clang::FrontendAction *ToolAction, const Twine &Code,
108                    const Twine &FileName,
109                    std::shared_ptr<PCHContainerOperations> PCHContainerOps) {
110   return runToolOnCodeWithArgs(ToolAction, Code, std::vector<std::string>(),
111                                FileName, "clang-tool",
112                                std::move(PCHContainerOps));
113 }
114 
115 static std::vector<std::string>
116 getSyntaxOnlyToolArgs(const Twine &ToolName,
117                       const std::vector<std::string> &ExtraArgs,
118                       StringRef FileName) {
119   std::vector<std::string> Args;
120   Args.push_back(ToolName.str());
121   Args.push_back("-fsyntax-only");
122   Args.insert(Args.end(), ExtraArgs.begin(), ExtraArgs.end());
123   Args.push_back(FileName.str());
124   return Args;
125 }
126 
127 bool runToolOnCodeWithArgs(
128     clang::FrontendAction *ToolAction, const Twine &Code,
129     const std::vector<std::string> &Args, const Twine &FileName,
130     const Twine &ToolName,
131     std::shared_ptr<PCHContainerOperations> PCHContainerOps,
132     const FileContentMappings &VirtualMappedFiles) {
133 
134   SmallString<16> FileNameStorage;
135   StringRef FileNameRef = FileName.toNullTerminatedStringRef(FileNameStorage);
136   llvm::IntrusiveRefCntPtr<vfs::OverlayFileSystem> OverlayFileSystem(
137       new vfs::OverlayFileSystem(vfs::getRealFileSystem()));
138   llvm::IntrusiveRefCntPtr<vfs::InMemoryFileSystem> InMemoryFileSystem(
139       new vfs::InMemoryFileSystem);
140   OverlayFileSystem->pushOverlay(InMemoryFileSystem);
141   llvm::IntrusiveRefCntPtr<FileManager> Files(
142       new FileManager(FileSystemOptions(), OverlayFileSystem));
143   ToolInvocation Invocation(getSyntaxOnlyToolArgs(ToolName, Args, FileNameRef),
144                             ToolAction, Files.get(),
145                             std::move(PCHContainerOps));
146 
147   SmallString<1024> CodeStorage;
148   InMemoryFileSystem->addFile(FileNameRef, 0,
149                               llvm::MemoryBuffer::getMemBuffer(
150                                   Code.toNullTerminatedStringRef(CodeStorage)));
151 
152   for (auto &FilenameWithContent : VirtualMappedFiles) {
153     InMemoryFileSystem->addFile(
154         FilenameWithContent.first, 0,
155         llvm::MemoryBuffer::getMemBuffer(FilenameWithContent.second));
156   }
157 
158   return Invocation.run();
159 }
160 
161 std::string getAbsolutePath(StringRef File) {
162   StringRef RelativePath(File);
163   // FIXME: Should '.\\' be accepted on Win32?
164   if (RelativePath.startswith("./")) {
165     RelativePath = RelativePath.substr(strlen("./"));
166   }
167 
168   SmallString<1024> AbsolutePath = RelativePath;
169   std::error_code EC = llvm::sys::fs::make_absolute(AbsolutePath);
170   assert(!EC);
171   (void)EC;
172   llvm::sys::path::native(AbsolutePath);
173   return AbsolutePath.str();
174 }
175 
176 void addTargetAndModeForProgramName(std::vector<std::string> &CommandLine,
177                                     StringRef InvokedAs) {
178   if (!CommandLine.empty() && !InvokedAs.empty()) {
179     bool AlreadyHasTarget = false;
180     bool AlreadyHasMode = false;
181     // Skip CommandLine[0].
182     for (auto Token = ++CommandLine.begin(); Token != CommandLine.end();
183          ++Token) {
184       StringRef TokenRef(*Token);
185       AlreadyHasTarget |=
186           (TokenRef == "-target" || TokenRef.startswith("-target="));
187       AlreadyHasMode |= (TokenRef == "--driver-mode" ||
188                          TokenRef.startswith("--driver-mode="));
189     }
190     auto TargetMode =
191         clang::driver::ToolChain::getTargetAndModeFromProgramName(InvokedAs);
192     if (!AlreadyHasMode && !TargetMode.second.empty()) {
193       CommandLine.insert(++CommandLine.begin(), TargetMode.second);
194     }
195     if (!AlreadyHasTarget && !TargetMode.first.empty()) {
196       CommandLine.insert(++CommandLine.begin(), {"-target", TargetMode.first});
197     }
198   }
199 }
200 
201 namespace {
202 
203 class SingleFrontendActionFactory : public FrontendActionFactory {
204   FrontendAction *Action;
205 
206 public:
207   SingleFrontendActionFactory(FrontendAction *Action) : Action(Action) {}
208 
209   FrontendAction *create() override { return Action; }
210 };
211 
212 }
213 
214 ToolInvocation::ToolInvocation(
215     std::vector<std::string> CommandLine, ToolAction *Action,
216     FileManager *Files, std::shared_ptr<PCHContainerOperations> PCHContainerOps)
217     : CommandLine(std::move(CommandLine)), Action(Action), OwnsAction(false),
218       Files(Files), PCHContainerOps(std::move(PCHContainerOps)),
219       DiagConsumer(nullptr) {}
220 
221 ToolInvocation::ToolInvocation(
222     std::vector<std::string> CommandLine, FrontendAction *FAction,
223     FileManager *Files, std::shared_ptr<PCHContainerOperations> PCHContainerOps)
224     : CommandLine(std::move(CommandLine)),
225       Action(new SingleFrontendActionFactory(FAction)), OwnsAction(true),
226       Files(Files), PCHContainerOps(std::move(PCHContainerOps)),
227       DiagConsumer(nullptr) {}
228 
229 ToolInvocation::~ToolInvocation() {
230   if (OwnsAction)
231     delete Action;
232 }
233 
234 void ToolInvocation::mapVirtualFile(StringRef FilePath, StringRef Content) {
235   SmallString<1024> PathStorage;
236   llvm::sys::path::native(FilePath, PathStorage);
237   MappedFileContents[PathStorage] = Content;
238 }
239 
240 bool ToolInvocation::run() {
241   std::vector<const char*> Argv;
242   for (const std::string &Str : CommandLine)
243     Argv.push_back(Str.c_str());
244   const char *const BinaryName = Argv[0];
245   IntrusiveRefCntPtr<DiagnosticOptions> DiagOpts = new DiagnosticOptions();
246   unsigned MissingArgIndex, MissingArgCount;
247   std::unique_ptr<llvm::opt::OptTable> Opts = driver::createDriverOptTable();
248   llvm::opt::InputArgList ParsedArgs = Opts->ParseArgs(
249       ArrayRef<const char *>(Argv).slice(1), MissingArgIndex, MissingArgCount);
250   ParseDiagnosticArgs(*DiagOpts, ParsedArgs);
251   TextDiagnosticPrinter DiagnosticPrinter(
252       llvm::errs(), &*DiagOpts);
253   DiagnosticsEngine Diagnostics(
254       IntrusiveRefCntPtr<clang::DiagnosticIDs>(new DiagnosticIDs()), &*DiagOpts,
255       DiagConsumer ? DiagConsumer : &DiagnosticPrinter, false);
256 
257   const std::unique_ptr<clang::driver::Driver> Driver(
258       newDriver(&Diagnostics, BinaryName, Files->getVirtualFileSystem()));
259   // Since the input might only be virtual, don't check whether it exists.
260   Driver->setCheckInputsExist(false);
261   const std::unique_ptr<clang::driver::Compilation> Compilation(
262       Driver->BuildCompilation(llvm::makeArrayRef(Argv)));
263   if (!Compilation)
264     return false;
265   const llvm::opt::ArgStringList *const CC1Args = getCC1Arguments(
266       &Diagnostics, Compilation.get());
267   if (!CC1Args) {
268     return false;
269   }
270   std::unique_ptr<clang::CompilerInvocation> Invocation(
271       newInvocation(&Diagnostics, *CC1Args));
272   // FIXME: remove this when all users have migrated!
273   for (const auto &It : MappedFileContents) {
274     // Inject the code as the given file name into the preprocessor options.
275     std::unique_ptr<llvm::MemoryBuffer> Input =
276         llvm::MemoryBuffer::getMemBuffer(It.getValue());
277     Invocation->getPreprocessorOpts().addRemappedFile(It.getKey(),
278                                                       Input.release());
279   }
280   return runInvocation(BinaryName, Compilation.get(), std::move(Invocation),
281                        std::move(PCHContainerOps));
282 }
283 
284 bool ToolInvocation::runInvocation(
285     const char *BinaryName, clang::driver::Compilation *Compilation,
286     std::shared_ptr<clang::CompilerInvocation> Invocation,
287     std::shared_ptr<PCHContainerOperations> PCHContainerOps) {
288   // Show the invocation, with -v.
289   if (Invocation->getHeaderSearchOpts().Verbose) {
290     llvm::errs() << "clang Invocation:\n";
291     Compilation->getJobs().Print(llvm::errs(), "\n", true);
292     llvm::errs() << "\n";
293   }
294 
295   return Action->runInvocation(std::move(Invocation), Files,
296                                std::move(PCHContainerOps), DiagConsumer);
297 }
298 
299 bool FrontendActionFactory::runInvocation(
300     std::shared_ptr<CompilerInvocation> Invocation, FileManager *Files,
301     std::shared_ptr<PCHContainerOperations> PCHContainerOps,
302     DiagnosticConsumer *DiagConsumer) {
303   // Create a compiler instance to handle the actual work.
304   clang::CompilerInstance Compiler(std::move(PCHContainerOps));
305   Compiler.setInvocation(std::move(Invocation));
306   Compiler.setFileManager(Files);
307 
308   // The FrontendAction can have lifetime requirements for Compiler or its
309   // members, and we need to ensure it's deleted earlier than Compiler. So we
310   // pass it to an std::unique_ptr declared after the Compiler variable.
311   std::unique_ptr<FrontendAction> ScopedToolAction(create());
312 
313   // Create the compiler's actual diagnostics engine.
314   Compiler.createDiagnostics(DiagConsumer, /*ShouldOwnClient=*/false);
315   if (!Compiler.hasDiagnostics())
316     return false;
317 
318   Compiler.createSourceManager(*Files);
319 
320   const bool Success = Compiler.ExecuteAction(*ScopedToolAction);
321 
322   Files->clearStatCaches();
323   return Success;
324 }
325 
326 ClangTool::ClangTool(const CompilationDatabase &Compilations,
327                      ArrayRef<std::string> SourcePaths,
328                      std::shared_ptr<PCHContainerOperations> PCHContainerOps)
329     : Compilations(Compilations), SourcePaths(SourcePaths),
330       PCHContainerOps(std::move(PCHContainerOps)),
331       OverlayFileSystem(new vfs::OverlayFileSystem(vfs::getRealFileSystem())),
332       InMemoryFileSystem(new vfs::InMemoryFileSystem),
333       Files(new FileManager(FileSystemOptions(), OverlayFileSystem)),
334       DiagConsumer(nullptr) {
335   OverlayFileSystem->pushOverlay(InMemoryFileSystem);
336   appendArgumentsAdjuster(getClangStripOutputAdjuster());
337   appendArgumentsAdjuster(getClangSyntaxOnlyAdjuster());
338 }
339 
340 ClangTool::~ClangTool() {}
341 
342 void ClangTool::mapVirtualFile(StringRef FilePath, StringRef Content) {
343   MappedFileContents.push_back(std::make_pair(FilePath, Content));
344 }
345 
346 void ClangTool::appendArgumentsAdjuster(ArgumentsAdjuster Adjuster) {
347   if (ArgsAdjuster)
348     ArgsAdjuster =
349         combineAdjusters(std::move(ArgsAdjuster), std::move(Adjuster));
350   else
351     ArgsAdjuster = std::move(Adjuster);
352 }
353 
354 void ClangTool::clearArgumentsAdjusters() {
355   ArgsAdjuster = nullptr;
356 }
357 
358 static void injectResourceDir(CommandLineArguments &Args, const char *Argv0,
359                               void *MainAddr) {
360   // Allow users to override the resource dir.
361   for (StringRef Arg : Args)
362     if (Arg.startswith("-resource-dir"))
363       return;
364 
365   // If there's no override in place add our resource dir.
366   Args.push_back("-resource-dir=" +
367                  CompilerInvocation::GetResourcesPath(Argv0, MainAddr));
368 }
369 
370 int ClangTool::run(ToolAction *Action) {
371   // Exists solely for the purpose of lookup of the resource path.
372   // This just needs to be some symbol in the binary.
373   static int StaticSymbol;
374 
375   llvm::SmallString<128> InitialDirectory;
376   if (std::error_code EC = llvm::sys::fs::current_path(InitialDirectory))
377     llvm::report_fatal_error("Cannot detect current path: " +
378                              Twine(EC.message()));
379 
380   // First insert all absolute paths into the in-memory VFS. These are global
381   // for all compile commands.
382   if (SeenWorkingDirectories.insert("/").second)
383     for (const auto &MappedFile : MappedFileContents)
384       if (llvm::sys::path::is_absolute(MappedFile.first))
385         InMemoryFileSystem->addFile(
386             MappedFile.first, 0,
387             llvm::MemoryBuffer::getMemBuffer(MappedFile.second));
388 
389   bool ProcessingFailed = false;
390   for (const auto &SourcePath : SourcePaths) {
391     std::string File(getAbsolutePath(SourcePath));
392 
393     // Currently implementations of CompilationDatabase::getCompileCommands can
394     // change the state of the file system (e.g.  prepare generated headers), so
395     // this method needs to run right before we invoke the tool, as the next
396     // file may require a different (incompatible) state of the file system.
397     //
398     // FIXME: Make the compilation database interface more explicit about the
399     // requirements to the order of invocation of its members.
400     std::vector<CompileCommand> CompileCommandsForFile =
401         Compilations.getCompileCommands(File);
402     if (CompileCommandsForFile.empty()) {
403       // FIXME: There are two use cases here: doing a fuzzy
404       // "find . -name '*.cc' |xargs tool" match, where as a user I don't care
405       // about the .cc files that were not found, and the use case where I
406       // specify all files I want to run over explicitly, where this should
407       // be an error. We'll want to add an option for this.
408       llvm::errs() << "Skipping " << File << ". Compile command not found.\n";
409       continue;
410     }
411     for (CompileCommand &CompileCommand : CompileCommandsForFile) {
412       // FIXME: chdir is thread hostile; on the other hand, creating the same
413       // behavior as chdir is complex: chdir resolves the path once, thus
414       // guaranteeing that all subsequent relative path operations work
415       // on the same path the original chdir resulted in. This makes a
416       // difference for example on network filesystems, where symlinks might be
417       // switched during runtime of the tool. Fixing this depends on having a
418       // file system abstraction that allows openat() style interactions.
419       if (OverlayFileSystem->setCurrentWorkingDirectory(
420               CompileCommand.Directory))
421         llvm::report_fatal_error("Cannot chdir into \"" +
422                                  Twine(CompileCommand.Directory) + "\n!");
423 
424       // Now fill the in-memory VFS with the relative file mappings so it will
425       // have the correct relative paths. We never remove mappings but that
426       // should be fine.
427       if (SeenWorkingDirectories.insert(CompileCommand.Directory).second)
428         for (const auto &MappedFile : MappedFileContents)
429           if (!llvm::sys::path::is_absolute(MappedFile.first))
430             InMemoryFileSystem->addFile(
431                 MappedFile.first, 0,
432                 llvm::MemoryBuffer::getMemBuffer(MappedFile.second));
433 
434       std::vector<std::string> CommandLine = CompileCommand.CommandLine;
435       if (ArgsAdjuster)
436         CommandLine = ArgsAdjuster(CommandLine, CompileCommand.Filename);
437       assert(!CommandLine.empty());
438 
439       // Add the resource dir based on the binary of this tool. argv[0] in the
440       // compilation database may refer to a different compiler and we want to
441       // pick up the very same standard library that compiler is using. The
442       // builtin headers in the resource dir need to match the exact clang
443       // version the tool is using.
444       // FIXME: On linux, GetMainExecutable is independent of the value of the
445       // first argument, thus allowing ClangTool and runToolOnCode to just
446       // pass in made-up names here. Make sure this works on other platforms.
447       injectResourceDir(CommandLine, "clang_tool", &StaticSymbol);
448 
449       // FIXME: We need a callback mechanism for the tool writer to output a
450       // customized message for each file.
451       DEBUG({ llvm::dbgs() << "Processing: " << File << ".\n"; });
452       ToolInvocation Invocation(std::move(CommandLine), Action, Files.get(),
453                                 PCHContainerOps);
454       Invocation.setDiagnosticConsumer(DiagConsumer);
455 
456       if (!Invocation.run()) {
457         // FIXME: Diagnostics should be used instead.
458         llvm::errs() << "Error while processing " << File << ".\n";
459         ProcessingFailed = true;
460       }
461       // Return to the initial directory to correctly resolve next file by
462       // relative path.
463       if (OverlayFileSystem->setCurrentWorkingDirectory(InitialDirectory.c_str()))
464         llvm::report_fatal_error("Cannot chdir into \"" +
465                                  Twine(InitialDirectory) + "\n!");
466     }
467   }
468   return ProcessingFailed ? 1 : 0;
469 }
470 
471 namespace {
472 
473 class ASTBuilderAction : public ToolAction {
474   std::vector<std::unique_ptr<ASTUnit>> &ASTs;
475 
476 public:
477   ASTBuilderAction(std::vector<std::unique_ptr<ASTUnit>> &ASTs) : ASTs(ASTs) {}
478 
479   bool runInvocation(std::shared_ptr<CompilerInvocation> Invocation,
480                      FileManager *Files,
481                      std::shared_ptr<PCHContainerOperations> PCHContainerOps,
482                      DiagnosticConsumer *DiagConsumer) override {
483     std::unique_ptr<ASTUnit> AST = ASTUnit::LoadFromCompilerInvocation(
484         Invocation, std::move(PCHContainerOps),
485         CompilerInstance::createDiagnostics(&Invocation->getDiagnosticOpts(),
486                                             DiagConsumer,
487                                             /*ShouldOwnClient=*/false),
488         Files);
489     if (!AST)
490       return false;
491 
492     ASTs.push_back(std::move(AST));
493     return true;
494   }
495 };
496 }
497 
498 int ClangTool::buildASTs(std::vector<std::unique_ptr<ASTUnit>> &ASTs) {
499   ASTBuilderAction Action(ASTs);
500   return run(&Action);
501 }
502 
503 std::unique_ptr<ASTUnit>
504 buildASTFromCode(const Twine &Code, const Twine &FileName,
505                  std::shared_ptr<PCHContainerOperations> PCHContainerOps) {
506   return buildASTFromCodeWithArgs(Code, std::vector<std::string>(), FileName,
507                                   "clang-tool", std::move(PCHContainerOps));
508 }
509 
510 std::unique_ptr<ASTUnit> buildASTFromCodeWithArgs(
511     const Twine &Code, const std::vector<std::string> &Args,
512     const Twine &FileName, const Twine &ToolName,
513     std::shared_ptr<PCHContainerOperations> PCHContainerOps) {
514   SmallString<16> FileNameStorage;
515   StringRef FileNameRef = FileName.toNullTerminatedStringRef(FileNameStorage);
516 
517   std::vector<std::unique_ptr<ASTUnit>> ASTs;
518   ASTBuilderAction Action(ASTs);
519   llvm::IntrusiveRefCntPtr<vfs::OverlayFileSystem> OverlayFileSystem(
520       new vfs::OverlayFileSystem(vfs::getRealFileSystem()));
521   llvm::IntrusiveRefCntPtr<vfs::InMemoryFileSystem> InMemoryFileSystem(
522       new vfs::InMemoryFileSystem);
523   OverlayFileSystem->pushOverlay(InMemoryFileSystem);
524   llvm::IntrusiveRefCntPtr<FileManager> Files(
525       new FileManager(FileSystemOptions(), OverlayFileSystem));
526   ToolInvocation Invocation(getSyntaxOnlyToolArgs(ToolName, Args, FileNameRef),
527                             &Action, Files.get(), std::move(PCHContainerOps));
528 
529   SmallString<1024> CodeStorage;
530   InMemoryFileSystem->addFile(FileNameRef, 0,
531                               llvm::MemoryBuffer::getMemBuffer(
532                                   Code.toNullTerminatedStringRef(CodeStorage)));
533   if (!Invocation.run())
534     return nullptr;
535 
536   assert(ASTs.size() == 1);
537   return std::move(ASTs[0]);
538 }
539 
540 } // end namespace tooling
541 } // end namespace clang
542