1//===--- ParsedAST.cpp -------------------------------------------*- 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 "ParsedAST.h"
10#include "../clang-tidy/ClangTidyCheck.h"
11#include "../clang-tidy/ClangTidyDiagnosticConsumer.h"
12#include "../clang-tidy/ClangTidyModule.h"
13#include "../clang-tidy/ClangTidyModuleRegistry.h"
14#include "../clang-tidy/ClangTidyOptions.h"
15#include "AST.h"
16#include "CollectMacros.h"
17#include "Compiler.h"
18#include "Config.h"
19#include "Diagnostics.h"
20#include "Feature.h"
21#include "FeatureModule.h"
22#include "Headers.h"
23#include "HeuristicResolver.h"
24#include "IncludeCleaner.h"
25#include "IncludeFixer.h"
26#include "Preamble.h"
27#include "SourceCode.h"
28#include "TidyProvider.h"
29#include "clang-include-cleaner/Record.h"
30#include "index/Symbol.h"
31#include "support/Logger.h"
32#include "support/Path.h"
33#include "support/Trace.h"
34#include "clang/AST/ASTContext.h"
35#include "clang/AST/Decl.h"
36#include "clang/AST/DeclGroup.h"
37#include "clang/AST/ExternalASTSource.h"
38#include "clang/ASTMatchers/ASTMatchFinder.h"
39#include "clang/Basic/Diagnostic.h"
40#include "clang/Basic/DiagnosticIDs.h"
41#include "clang/Basic/DiagnosticSema.h"
42#include "clang/Basic/FileEntry.h"
43#include "clang/Basic/LLVM.h"
44#include "clang/Basic/LangOptions.h"
45#include "clang/Basic/SourceLocation.h"
46#include "clang/Basic/SourceManager.h"
47#include "clang/Basic/TokenKinds.h"
48#include "clang/Frontend/CompilerInstance.h"
49#include "clang/Frontend/CompilerInvocation.h"
50#include "clang/Frontend/FrontendActions.h"
51#include "clang/Frontend/FrontendOptions.h"
52#include "clang/Frontend/PrecompiledPreamble.h"
53#include "clang/Lex/Lexer.h"
54#include "clang/Lex/PPCallbacks.h"
55#include "clang/Lex/Preprocessor.h"
56#include "clang/Serialization/ASTWriter.h"
57#include "clang/Tooling/CompilationDatabase.h"
58#include "clang/Tooling/Core/Diagnostic.h"
59#include "clang/Tooling/Syntax/Tokens.h"
60#include "llvm/ADT/ArrayRef.h"
61#include "llvm/ADT/DenseMap.h"
62#include "llvm/ADT/DenseSet.h"
63#include "llvm/ADT/STLExtras.h"
64#include "llvm/ADT/STLFunctionalExtras.h"
65#include "llvm/ADT/SmallVector.h"
66#include "llvm/ADT/StringRef.h"
67#include "llvm/Support/Error.h"
68#include "llvm/Support/MemoryBuffer.h"
69#include <cassert>
70#include <cstddef>
71#include <iterator>
72#include <memory>
73#include <optional>
74#include <string>
75#include <tuple>
76#include <utility>
77#include <vector>
78
79// Force the linker to link in Clang-tidy modules.
80// clangd doesn't support the static analyzer.
81#if CLANGD_TIDY_CHECKS
82#define CLANG_TIDY_DISABLE_STATIC_ANALYZER_CHECKS
83#include "../clang-tidy/ClangTidyForceLinker.h"
84#endif
85
86namespace clang {
87namespace clangd {
88namespace {
89
90template <class T> std::size_t getUsedBytes(const std::vector<T> &Vec) {
91 return Vec.capacity() * sizeof(T);
92}
93
94class DeclTrackingASTConsumer : public ASTConsumer {
95public:
96 DeclTrackingASTConsumer(std::vector<Decl *> &TopLevelDecls)
97 : TopLevelDecls(TopLevelDecls) {}
98
99 bool HandleTopLevelDecl(DeclGroupRef DG) override {
100 for (Decl *D : DG) {
101 auto &SM = D->getASTContext().getSourceManager();
102 if (!isInsideMainFile(D->getLocation(), SM))
103 continue;
104 if (const NamedDecl *ND = dyn_cast<NamedDecl>(D))
105 if (isImplicitTemplateInstantiation(ND))
106 continue;
107
108 // ObjCMethodDecl are not actually top-level decls.
109 if (isa<ObjCMethodDecl>(D))
110 continue;
111
112 TopLevelDecls.push_back(D);
113 }
114 return true;
115 }
116
117private:
118 std::vector<Decl *> &TopLevelDecls;
119};
120
121class ClangdFrontendAction : public SyntaxOnlyAction {
122public:
123 std::vector<Decl *> takeTopLevelDecls() { return std::move(TopLevelDecls); }
124
125protected:
126 std::unique_ptr<ASTConsumer>
127 CreateASTConsumer(CompilerInstance &CI, llvm::StringRef InFile) override {
128 return std::make_unique<DeclTrackingASTConsumer>(/*ref*/ TopLevelDecls);
129 }
130
131private:
132 std::vector<Decl *> TopLevelDecls;
133};
134
135// When using a preamble, only preprocessor events outside its bounds are seen.
136// This is almost what we want: replaying transitive preprocessing wastes time.
137// However this confuses clang-tidy checks: they don't see any #includes!
138// So we replay the *non-transitive* #includes that appear in the main-file.
139// It would be nice to replay other events (macro definitions, ifdefs etc) but
140// this addresses the most common cases fairly cheaply.
141class ReplayPreamble : private PPCallbacks {
142public:
143 // Attach preprocessor hooks such that preamble events will be injected at
144 // the appropriate time.
145 // Events will be delivered to the *currently registered* PP callbacks.
146 static void attach(std::vector<Inclusion> Includes, CompilerInstance &Clang,
147 const PreambleBounds &PB) {
148 auto &PP = Clang.getPreprocessor();
149 auto *ExistingCallbacks = PP.getPPCallbacks();
150 // No need to replay events if nobody is listening.
151 if (!ExistingCallbacks)
152 return;
153 PP.addPPCallbacks(std::unique_ptr<PPCallbacks>(new ReplayPreamble(
154 std::move(Includes), ExistingCallbacks, Clang.getSourceManager(), PP,
155 Clang.getLangOpts(), PB)));
156 // We're relying on the fact that addPPCallbacks keeps the old PPCallbacks
157 // around, creating a chaining wrapper. Guard against other implementations.
158 assert(PP.getPPCallbacks() != ExistingCallbacks &&
159 "Expected chaining implementation");
160 }
161
162private:
163 ReplayPreamble(std::vector<Inclusion> Includes, PPCallbacks *Delegate,
164 const SourceManager &SM, Preprocessor &PP,
165 const LangOptions &LangOpts, const PreambleBounds &PB)
166 : Includes(std::move(Includes)), Delegate(Delegate), SM(SM), PP(PP) {
167 // Only tokenize the preamble section of the main file, as we are not
168 // interested in the rest of the tokens.
169 MainFileTokens = syntax::tokenize(
170 syntax::FileRange(SM.getMainFileID(), 0, PB.Size), SM, LangOpts);
171 }
172
173 // In a normal compile, the preamble traverses the following structure:
174 //
175 // mainfile.cpp
176 // <built-in>
177 // ... macro definitions like __cplusplus ...
178 // <command-line>
179 // ... macro definitions for args like -Dfoo=bar ...
180 // "header1.h"
181 // ... header file contents ...
182 // "header2.h"
183 // ... header file contents ...
184 // ... main file contents ...
185 //
186 // When using a preamble, the "header1" and "header2" subtrees get skipped.
187 // We insert them right after the built-in header, which still appears.
188 void FileChanged(SourceLocation Loc, FileChangeReason Reason,
189 SrcMgr::CharacteristicKind Kind, FileID PrevFID) override {
190 // It'd be nice if there was a better way to identify built-in headers...
191 if (Reason == FileChangeReason::ExitFile &&
192 SM.getBufferOrFake(PrevFID).getBufferIdentifier() == "<built-in>")
193 replay();
194 }
195
196 void replay() {
197 for (const auto &Inc : Includes) {
198 OptionalFileEntryRef File;
199 if (Inc.Resolved != "")
200 File = expectedToOptional(SM.getFileManager().getFileRef(Inc.Resolved));
201
202 // Re-lex the #include directive to find its interesting parts.
203 auto HashLoc = SM.getComposedLoc(SM.getMainFileID(), Inc.HashOffset);
204 auto HashTok = llvm::partition_point(MainFileTokens,
205 [&HashLoc](const syntax::Token &T) {
206 return T.location() < HashLoc;
207 });
208 assert(HashTok != MainFileTokens.end() && HashTok->kind() == tok::hash);
209
210 auto IncludeTok = std::next(HashTok);
211 assert(IncludeTok != MainFileTokens.end());
212
213 auto FileTok = std::next(IncludeTok);
214 assert(FileTok != MainFileTokens.end());
215
216 // Create a fake import/include token, none of the callers seem to care
217 // about clang::Token::Flags.
218 Token SynthesizedIncludeTok;
219 SynthesizedIncludeTok.startToken();
220 SynthesizedIncludeTok.setLocation(IncludeTok->location());
221 SynthesizedIncludeTok.setLength(IncludeTok->length());
222 SynthesizedIncludeTok.setKind(tok::raw_identifier);
223 SynthesizedIncludeTok.setRawIdentifierData(IncludeTok->text(SM).data());
224 PP.LookUpIdentifierInfo(SynthesizedIncludeTok);
225
226 // Same here, create a fake one for Filename, including angles or quotes.
227 Token SynthesizedFilenameTok;
228 SynthesizedFilenameTok.startToken();
229 SynthesizedFilenameTok.setLocation(FileTok->location());
230 // Note that we can't make use of FileTok->length/text in here as in the
231 // case of angled includes this will contain tok::less instead of
232 // filename. Whereas Inc.Written contains the full header name including
233 // quotes/angles.
234 SynthesizedFilenameTok.setLength(Inc.Written.length());
235 SynthesizedFilenameTok.setKind(tok::header_name);
236 SynthesizedFilenameTok.setLiteralData(Inc.Written.data());
237
238 llvm::StringRef WrittenFilename =
239 llvm::StringRef(Inc.Written).drop_front().drop_back();
240 Delegate->InclusionDirective(
241 HashTok->location(), SynthesizedIncludeTok, WrittenFilename,
242 Inc.Written.front() == '<',
243 syntax::FileRange(SM, SynthesizedFilenameTok.getLocation(),
244 SynthesizedFilenameTok.getEndLoc())
245 .toCharRange(SM),
246 File, "SearchPath", "RelPath",
247 /*Imported=*/nullptr, Inc.FileKind);
248 if (File)
249 Delegate->FileSkipped(*File, SynthesizedFilenameTok, Inc.FileKind);
250 }
251 }
252
253 const std::vector<Inclusion> Includes;
254 PPCallbacks *Delegate;
255 const SourceManager &SM;
256 Preprocessor &PP;
257 std::vector<syntax::Token> MainFileTokens;
258};
259
260// Filter for clang diagnostics groups enabled by CTOptions.Checks.
261//
262// These are check names like clang-diagnostics-unused.
263// Note that unlike -Wunused, clang-diagnostics-unused does not imply
264// subcategories like clang-diagnostics-unused-function.
265//
266// This is used to determine which diagnostics can be enabled by ExtraArgs in
267// the clang-tidy configuration.
268class TidyDiagnosticGroups {
269 // Whether all diagnostic groups are enabled by default.
270 // True if we've seen clang-diagnostic-*.
271 bool Default = false;
272 // Set of diag::Group whose enablement != Default.
273 // If Default is false, this is foo where we've seen clang-diagnostic-foo.
274 llvm::DenseSet<unsigned> Exceptions;
275
276public:
277 TidyDiagnosticGroups(llvm::StringRef Checks) {
278 constexpr llvm::StringLiteral CDPrefix = "clang-diagnostic-";
279
280 llvm::StringRef Check;
281 while (!Checks.empty()) {
282 std::tie(Check, Checks) = Checks.split(',');
283 if (Check.empty())
284 continue;
285
286 bool Enable = !Check.consume_front("-");
287 bool Glob = Check.consume_back("*");
288 if (Glob) {
289 // Is this clang-diagnostic-*, or *, or so?
290 // (We ignore all other types of globs).
291 if (CDPrefix.startswith(Check)) {
292 Default = Enable;
293 Exceptions.clear();
294 }
295 continue;
296 }
297
298 // In "*,clang-diagnostic-foo", the latter is a no-op.
299 if (Default == Enable)
300 continue;
301 // The only non-glob entries we care about are clang-diagnostic-foo.
302 if (!Check.consume_front(CDPrefix))
303 continue;
304
305 if (auto Group = DiagnosticIDs::getGroupForWarningOption(Check))
306 Exceptions.insert(static_cast<unsigned>(*Group));
307 }
308 }
309
310 bool operator()(diag::Group GroupID) const {
311 return Exceptions.contains(static_cast<unsigned>(GroupID)) ? !Default
312 : Default;
313 }
314};
315
316// Find -W<group> and -Wno-<group> options in ExtraArgs and apply them to Diags.
317//
318// This is used to handle ExtraArgs in clang-tidy configuration.
319// We don't use clang's standard handling of this as we want slightly different
320// behavior (e.g. we want to exclude these from -Wno-error).
321void applyWarningOptions(llvm::ArrayRef<std::string> ExtraArgs,
322 llvm::function_ref<bool(diag::Group)> EnabledGroups,
323 DiagnosticsEngine &Diags) {
324 for (llvm::StringRef Group : ExtraArgs) {
325 // Only handle args that are of the form -W[no-]<group>.
326 // Other flags are possible but rare and deliberately out of scope.
327 llvm::SmallVector<diag::kind> Members;
328 if (!Group.consume_front("-W") || Group.empty())
329 continue;
330 bool Enable = !Group.consume_front("no-");
331 if (Diags.getDiagnosticIDs()->getDiagnosticsInGroup(
332 diag::Flavor::WarningOrError, Group, Members))
333 continue;
334
335 // Upgrade (or downgrade) the severity of each diagnostic in the group.
336 // If -Werror is on, newly added warnings will be treated as errors.
337 // We don't want this, so keep track of them to fix afterwards.
338 bool NeedsWerrorExclusion = false;
339 for (diag::kind ID : Members) {
340 if (Enable) {
341 if (Diags.getDiagnosticLevel(ID, SourceLocation()) <
342 DiagnosticsEngine::Warning) {
343 auto Group = DiagnosticIDs::getGroupForDiag(ID);
344 if (!Group || !EnabledGroups(*Group))
345 continue;
346 Diags.setSeverity(ID, diag::Severity::Warning, SourceLocation());
347 if (Diags.getWarningsAsErrors())
348 NeedsWerrorExclusion = true;
349 }
350 } else {
351 Diags.setSeverity(ID, diag::Severity::Ignored, SourceLocation());
352 }
353 }
354 if (NeedsWerrorExclusion) {
355 // FIXME: there's no API to suppress -Werror for single diagnostics.
356 // In some cases with sub-groups, we may end up erroneously
357 // downgrading diagnostics that were -Werror in the compile command.
358 Diags.setDiagnosticGroupWarningAsError(Group, false);
359 }
360 }
361}
362
363std::vector<Diag> getIncludeCleanerDiags(ParsedAST &AST, llvm::StringRef Code) {
364 auto &Cfg = Config::current();
365 if (Cfg.Diagnostics.SuppressAll)
366 return {};
367 bool SuppressMissing =
368 Cfg.Diagnostics.Suppress.contains("missing-includes") ||
369 Cfg.Diagnostics.MissingIncludes == Config::IncludesPolicy::None;
370 bool SuppressUnused =
371 Cfg.Diagnostics.Suppress.contains("unused-includes") ||
372 Cfg.Diagnostics.UnusedIncludes == Config::IncludesPolicy::None;
373 if (SuppressMissing && SuppressUnused)
374 return {};
375 auto Findings = computeIncludeCleanerFindings(AST);
376 if (SuppressMissing)
377 Findings.MissingIncludes.clear();
378 if (SuppressUnused)
379 Findings.UnusedIncludes.clear();
380 return issueIncludeCleanerDiagnostics(AST, Code, Findings,
381 Cfg.Diagnostics.Includes.IgnoreHeader);
382}
383
384} // namespace
385
386std::optional<ParsedAST>
387ParsedAST::build(llvm::StringRef Filename, const ParseInputs &Inputs,
388 std::unique_ptr<clang::CompilerInvocation> CI,
389 llvm::ArrayRef<Diag> CompilerInvocationDiags,
390 std::shared_ptr<const PreambleData> Preamble) {
391 trace::Span Tracer("BuildAST");
392 SPAN_ATTACH(Tracer, "File", Filename);
393
394 auto VFS = Inputs.TFS->view(Inputs.CompileCommand.Directory);
395 if (Preamble && Preamble->StatCache)
396 VFS = Preamble->StatCache->getConsumingFS(std::move(VFS));
397
398 assert(CI);
399 // Command-line parsing sets DisableFree to true by default, but we don't want
400 // to leak memory in clangd.
401 CI->getFrontendOpts().DisableFree = false;
402 const PrecompiledPreamble *PreamblePCH =
403 Preamble ? &Preamble->Preamble : nullptr;
404
405 // This is on-by-default in windows to allow parsing SDK headers, but it
406 // breaks many features. Disable it for the main-file (not preamble).
407 CI->getLangOpts()->DelayedTemplateParsing = false;
408
409 std::vector<std::unique_ptr<FeatureModule::ASTListener>> ASTListeners;
410 if (Inputs.FeatureModules) {
411 for (auto &M : *Inputs.FeatureModules) {
412 if (auto Listener = M.astListeners())
413 ASTListeners.emplace_back(std::move(Listener));
414 }
415 }
416 StoreDiags ASTDiags;
417 ASTDiags.setDiagCallback(
418 [&ASTListeners](const clang::Diagnostic &D, clangd::Diag &Diag) {
419 llvm::for_each(ASTListeners,
420 [&](const auto &L) { L->sawDiagnostic(D, Diag); });
421 });
422
423 std::optional<PreamblePatch> Patch;
424 // We might use an ignoring diagnostic consumer if they are going to be
425 // dropped later on to not pay for extra latency by processing them.
426 DiagnosticConsumer *DiagConsumer = &ASTDiags;
427 IgnoreDiagnostics DropDiags;
428 if (Preamble) {
429 Patch = PreamblePatch::createFullPatch(Filename, Inputs, *Preamble);
430 Patch->apply(*CI);
431 }
432 auto Clang = prepareCompilerInstance(
433 std::move(CI), PreamblePCH,
434 llvm::MemoryBuffer::getMemBufferCopy(Inputs.Contents, Filename), VFS,
435 *DiagConsumer);
436 if (!Clang) {
437 // The last diagnostic contains information about the reason of this
438 // failure.
439 std::vector<Diag> Diags(ASTDiags.take());
440 elog("Failed to prepare a compiler instance: {0}",
441 !Diags.empty() ? static_cast<DiagBase &>(Diags.back()).Message
442 : "unknown error");
443 return std::nullopt;
444 }
445 tidy::ClangTidyOptions ClangTidyOpts;
446 {
447 trace::Span Tracer("ClangTidyOpts");
448 ClangTidyOpts = getTidyOptionsForFile(Inputs.ClangTidyProvider, Filename);
449 dlog("ClangTidy configuration for file {0}: {1}", Filename,
450 tidy::configurationAsText(ClangTidyOpts));
451
452 // If clang-tidy is configured to emit clang warnings, we should too.
453 //
454 // Such clang-tidy configuration consists of two parts:
455 // - ExtraArgs: ["-Wfoo"] causes clang to produce the warnings
456 // - Checks: "clang-diagnostic-foo" prevents clang-tidy filtering them out
457 //
458 // In clang-tidy, diagnostics are emitted if they pass both checks.
459 // When groups contain subgroups, -Wparent includes the child, but
460 // clang-diagnostic-parent does not.
461 //
462 // We *don't* want to change the compile command directly. This can have
463 // too many unexpected effects: breaking the command, interactions with
464 // -- and -Werror, etc. Besides, we've already parsed the command.
465 // Instead we parse the -W<group> flags and handle them directly.
466 //
467 // Similarly, we don't want to use Checks to filter clang diagnostics after
468 // they are generated, as this spreads clang-tidy emulation everywhere.
469 // Instead, we just use these to filter which extra diagnostics we enable.
470 auto &Diags = Clang->getDiagnostics();
471 TidyDiagnosticGroups TidyGroups(ClangTidyOpts.Checks ? *ClangTidyOpts.Checks
472 : llvm::StringRef());
473 if (ClangTidyOpts.ExtraArgsBefore)
474 applyWarningOptions(*ClangTidyOpts.ExtraArgsBefore, TidyGroups, Diags);
475 if (ClangTidyOpts.ExtraArgs)
476 applyWarningOptions(*ClangTidyOpts.ExtraArgs, TidyGroups, Diags);
477 }
478
479 auto Action = std::make_unique<ClangdFrontendAction>();
480 const FrontendInputFile &MainInput = Clang->getFrontendOpts().Inputs[0];
481 if (!Action->BeginSourceFile(*Clang, MainInput)) {
482 log("BeginSourceFile() failed when building AST for {0}",
483 MainInput.getFile());
484 return std::nullopt;
485 }
486 // If we saw an include guard in the preamble section of the main file,
487 // mark the main-file as include-guarded.
488 // This information is part of the HeaderFileInfo but is not loaded from the
489 // preamble as the file's size is part of its identity and may have changed.
490 // (The rest of HeaderFileInfo is not relevant for our purposes).
491 if (Preamble && Preamble->MainIsIncludeGuarded) {
492 const SourceManager &SM = Clang->getSourceManager();
493 const FileEntry *MainFE = SM.getFileEntryForID(SM.getMainFileID());
494 Clang->getPreprocessor().getHeaderSearchInfo().MarkFileIncludeOnce(MainFE);
495 }
496
497 // Set up ClangTidy. Must happen after BeginSourceFile() so ASTContext exists.
498 // Clang-tidy has some limitations to ensure reasonable performance:
499 // - checks don't see all preprocessor events in the preamble
500 // - matchers run only over the main-file top-level decls (and can't see
501 // ancestors outside this scope).
502 // In practice almost all checks work well without modifications.
503 std::vector<std::unique_ptr<tidy::ClangTidyCheck>> CTChecks;
504 ast_matchers::MatchFinder CTFinder;
505 std::optional<tidy::ClangTidyContext> CTContext;
506 // Must outlive FixIncludes.
507 auto BuildDir = VFS->getCurrentWorkingDirectory();
508 std::optional<IncludeFixer> FixIncludes;
509 llvm::DenseMap<diag::kind, DiagnosticsEngine::Level> OverriddenSeverity;
510 // No need to run clang-tidy or IncludeFixerif we are not going to surface
511 // diagnostics.
512 {
513 trace::Span Tracer("ClangTidyInit");
514 static const auto *CTFactories = [] {
515 auto *CTFactories = new tidy::ClangTidyCheckFactories;
516 for (const auto &E : tidy::ClangTidyModuleRegistry::entries())
517 E.instantiate()->addCheckFactories(*CTFactories);
518 return CTFactories;
519 }();
520 CTContext.emplace(std::make_unique<tidy::DefaultOptionsProvider>(
521 tidy::ClangTidyGlobalOptions(), ClangTidyOpts));
522 CTContext->setDiagnosticsEngine(&Clang->getDiagnostics());
523 CTContext->setASTContext(&Clang->getASTContext());
524 CTContext->setCurrentFile(Filename);
525 CTContext->setSelfContainedDiags(true);
526 CTChecks = CTFactories->createChecksForLanguage(&*CTContext);
527 Preprocessor *PP = &Clang->getPreprocessor();
528 for (const auto &Check : CTChecks) {
529 Check->registerPPCallbacks(Clang->getSourceManager(), PP, PP);
530 Check->registerMatchers(&CTFinder);
531 }
532
533 // Clang only corrects typos for use of undeclared functions in C if that
534 // use is an error. Include fixer relies on typo correction, so pretend
535 // this is an error. (The actual typo correction is nice too).
536 // We restore the original severity in the level adjuster.
537 // FIXME: It would be better to have a real API for this, but what?
538 for (auto ID : {diag::ext_implicit_function_decl_c99,
539 diag::ext_implicit_lib_function_decl,
540 diag::ext_implicit_lib_function_decl_c99,
541 diag::warn_implicit_function_decl}) {
542 OverriddenSeverity.try_emplace(
543 ID, Clang->getDiagnostics().getDiagnosticLevel(ID, SourceLocation()));
544 Clang->getDiagnostics().setSeverity(ID, diag::Severity::Error,
545 SourceLocation());
546 }
547
548 const Config &Cfg = Config::current();
549 ASTDiags.setLevelAdjuster([&](DiagnosticsEngine::Level DiagLevel,
550 const clang::Diagnostic &Info) {
551 if (Cfg.Diagnostics.SuppressAll ||
552 isBuiltinDiagnosticSuppressed(Info.getID(), Cfg.Diagnostics.Suppress,
553 Clang->getLangOpts()))
554 return DiagnosticsEngine::Ignored;
555
556 auto It = OverriddenSeverity.find(Info.getID());
557 if (It != OverriddenSeverity.end())
558 DiagLevel = It->second;
559
560 if (!CTChecks.empty()) {
561 std::string CheckName = CTContext->getCheckName(Info.getID());
562 bool IsClangTidyDiag = !CheckName.empty();
563 if (IsClangTidyDiag) {
564 if (Cfg.Diagnostics.Suppress.contains(CheckName))
565 return DiagnosticsEngine::Ignored;
566 // Check for suppression comment. Skip the check for diagnostics not
567 // in the main file, because we don't want that function to query the
568 // source buffer for preamble files. For the same reason, we ask
569 // shouldSuppressDiagnostic to avoid I/O.
570 // We let suppression comments take precedence over warning-as-error
571 // to match clang-tidy's behaviour.
572 bool IsInsideMainFile =
573 Info.hasSourceManager() &&
574 isInsideMainFile(Info.getLocation(), Info.getSourceManager());
575 SmallVector<tooling::Diagnostic, 1> TidySuppressedErrors;
576 if (IsInsideMainFile && CTContext->shouldSuppressDiagnostic(
577 DiagLevel, Info, TidySuppressedErrors,
578 /*AllowIO=*/false,
579 /*EnableNolintBlocks=*/true)) {
580 // FIXME: should we expose the suppression error (invalid use of
581 // NOLINT comments)?
582 return DiagnosticsEngine::Ignored;
583 }
584 if (!CTContext->getOptions().SystemHeaders.value_or(false) &&
585 Info.hasSourceManager() &&
586 Info.getSourceManager().isInSystemMacro(Info.getLocation()))
587 return DiagnosticsEngine::Ignored;
588
589 // Check for warning-as-error.
590 if (DiagLevel == DiagnosticsEngine::Warning &&
591 CTContext->treatAsError(CheckName)) {
592 return DiagnosticsEngine::Error;
593 }
594 }
595 }
596 return DiagLevel;
597 });
598
599 // Add IncludeFixer which can recover diagnostics caused by missing includes
600 // (e.g. incomplete type) and attach include insertion fixes to diagnostics.
601 if (Inputs.Index && !BuildDir.getError()) {
602 auto Style =
603 getFormatStyleForFile(Filename, Inputs.Contents, *Inputs.TFS);
604 auto Inserter = std::make_shared<IncludeInserter>(
605 Filename, Inputs.Contents, Style, BuildDir.get(),
606 &Clang->getPreprocessor().getHeaderSearchInfo());
607 ArrayRef<Inclusion> MainFileIncludes;
608 if (Preamble) {
609 MainFileIncludes = Preamble->Includes.MainFileIncludes;
610 for (const auto &Inc : Preamble->Includes.MainFileIncludes)
611 Inserter->addExisting(Inc);
612 }
613 // FIXME: Consider piping through ASTSignals to fetch this to handle the
614 // case where a header file contains ObjC decls but no #imports.
615 Symbol::IncludeDirective Directive =
616 Inputs.Opts.ImportInsertions
617 ? preferredIncludeDirective(Filename, Clang->getLangOpts(),
618 MainFileIncludes, {})
619 : Symbol::Include;
620 FixIncludes.emplace(Filename, Inserter, *Inputs.Index,
621 /*IndexRequestLimit=*/5, Directive);
622 ASTDiags.contributeFixes([&FixIncludes](DiagnosticsEngine::Level DiagLevl,
623 const clang::Diagnostic &Info) {
624 return FixIncludes->fix(DiagLevl, Info);
625 });
626 Clang->setExternalSemaSource(FixIncludes->unresolvedNameRecorder());
627 }
628 }
629
630 IncludeStructure Includes;
631 // If we are using a preamble, copy existing includes.
632 if (Preamble) {
633 Includes = Preamble->Includes;
634 Includes.MainFileIncludes = Patch->preambleIncludes();
635 // Replay the preamble includes so that clang-tidy checks can see them.
636 ReplayPreamble::attach(Patch->preambleIncludes(), *Clang,
637 Patch->modifiedBounds());
638 }
639 // Important: collectIncludeStructure is registered *after* ReplayPreamble!
640 // Otherwise we would collect the replayed includes again...
641 // (We can't *just* use the replayed includes, they don't have Resolved path).
642 Includes.collect(*Clang);
643 // Copy over the macros in the preamble region of the main file, and combine
644 // with non-preamble macros below.
645 MainFileMacros Macros;
646 std::vector<PragmaMark> Marks;
647 if (Preamble) {
648 Macros = Patch->mainFileMacros();
649 Marks = Patch->marks();
650 }
651 auto &PP = Clang->getPreprocessor();
652 PP.addPPCallbacks(std::make_unique<CollectMainFileMacros>(PP, Macros));
653
654 PP.addPPCallbacks(
655 collectPragmaMarksCallback(Clang->getSourceManager(), Marks));
656
657 // FIXME: Attach a comment handler to take care of
658 // keep/export/no_include etc. IWYU pragmas.
659
660 // Collect tokens of the main file.
661 syntax::TokenCollector CollectTokens(PP);
662
663 // To remain consistent with preamble builds, these callbacks must be called
664 // exactly here, after preprocessor is initialized and BeginSourceFile() was
665 // called already.
666 for (const auto &L : ASTListeners)
667 L->beforeExecute(*Clang);
668
669 if (llvm::Error Err = Action->Execute())
670 log("Execute() failed when building AST for {0}: {1}", MainInput.getFile(),
671 toString(std::move(Err)));
672
673 // We have to consume the tokens before running clang-tidy to avoid collecting
674 // tokens from running the preprocessor inside the checks (only
675 // modernize-use-trailing-return-type does that today).
676 syntax::TokenBuffer Tokens = std::move(CollectTokens).consume();
677 // Makes SelectionTree build much faster.
678 Tokens.indexExpandedTokens();
679 std::vector<Decl *> ParsedDecls = Action->takeTopLevelDecls();
680 // AST traversals should exclude the preamble, to avoid performance cliffs.
681 Clang->getASTContext().setTraversalScope(ParsedDecls);
682 if (!CTChecks.empty()) {
683 // Run the AST-dependent part of the clang-tidy checks.
684 // (The preprocessor part ran already, via PPCallbacks).
685 trace::Span Tracer("ClangTidyMatch");
686 CTFinder.matchAST(Clang->getASTContext());
687 }
688
689 // XXX: This is messy: clang-tidy checks flush some diagnostics at EOF.
690 // However Action->EndSourceFile() would destroy the ASTContext!
691 // So just inform the preprocessor of EOF, while keeping everything alive.
692 PP.EndSourceFile();
693 // UnitDiagsConsumer is local, we can not store it in CompilerInstance that
694 // has a longer lifetime.
695 Clang->getDiagnostics().setClient(new IgnoreDiagnostics);
696 // CompilerInstance won't run this callback, do it directly.
697 ASTDiags.EndSourceFile();
698
699 std::vector<Diag> Diags = CompilerInvocationDiags;
700 // FIXME: Also skip generation of diagnostics altogether to speed up ast
701 // builds when we are patching a stale preamble.
702 // Add diagnostics from the preamble, if any.
703 if (Preamble)
704 llvm::append_range(Diags, Patch->patchedDiags());
705 // Finally, add diagnostics coming from the AST.
706 {
707 std::vector<Diag> D = ASTDiags.take(&*CTContext);
708 Diags.insert(Diags.end(), D.begin(), D.end());
709 }
710 ParsedAST Result(Filename, Inputs.Version, std::move(Preamble),
711 std::move(Clang), std::move(Action), std::move(Tokens),
712 std::move(Macros), std::move(Marks), std::move(ParsedDecls),
713 std::move(Diags), std::move(Includes));
714 llvm::move(getIncludeCleanerDiags(Result, Inputs.Contents),
715 std::back_inserter(Result.Diags));
716 return std::move(Result);
717}
718
719ParsedAST::ParsedAST(ParsedAST &&Other) = default;
720
721ParsedAST &ParsedAST::operator=(ParsedAST &&Other) = default;
722
723ParsedAST::~ParsedAST() {
724 if (Action) {
725 // We already notified the PP of end-of-file earlier, so detach it first.
726 // We must keep it alive until after EndSourceFile(), Sema relies on this.
727 auto PP = Clang->getPreprocessorPtr(); // Keep PP alive for now.
728 Clang->setPreprocessor(nullptr); // Detach so we don't send EOF again.
729 Action->EndSourceFile(); // Destroy ASTContext and Sema.
730 // Now Sema is gone, it's safe for PP to go out of scope.
731 }
732}
733
734ASTContext &ParsedAST::getASTContext() { return Clang->getASTContext(); }
735
736const ASTContext &ParsedAST::getASTContext() const {
737 return Clang->getASTContext();
738}
739
740Sema &ParsedAST::getSema() { return Clang->getSema(); }
741
742Preprocessor &ParsedAST::getPreprocessor() { return Clang->getPreprocessor(); }
743
744std::shared_ptr<Preprocessor> ParsedAST::getPreprocessorPtr() {
745 return Clang->getPreprocessorPtr();
746}
747
748const Preprocessor &ParsedAST::getPreprocessor() const {
749 return Clang->getPreprocessor();
750}
751
752llvm::ArrayRef<Decl *> ParsedAST::getLocalTopLevelDecls() {
753 return LocalTopLevelDecls;
754}
755
756llvm::ArrayRef<const Decl *> ParsedAST::getLocalTopLevelDecls() const {
757 return LocalTopLevelDecls;
758}
759
760const MainFileMacros &ParsedAST::getMacros() const { return Macros; }
761const std::vector<PragmaMark> &ParsedAST::getMarks() const { return Marks; }
762
763std::size_t ParsedAST::getUsedBytes() const {
764 auto &AST = getASTContext();
765 // FIXME(ibiryukov): we do not account for the dynamically allocated part of
766 // Message and Fixes inside each diagnostic.
767 std::size_t Total =
768 clangd::getUsedBytes(LocalTopLevelDecls) + clangd::getUsedBytes(Diags);
769
770 // FIXME: the rest of the function is almost a direct copy-paste from
771 // libclang's clang_getCXTUResourceUsage. We could share the implementation.
772
773 // Sum up various allocators inside the ast context and the preprocessor.
774 Total += AST.getASTAllocatedMemory();
775 Total += AST.getSideTableAllocatedMemory();
776 Total += AST.Idents.getAllocator().getTotalMemory();
777 Total += AST.Selectors.getTotalMemory();
778
779 Total += AST.getSourceManager().getContentCacheSize();
780 Total += AST.getSourceManager().getDataStructureSizes();
781 Total += AST.getSourceManager().getMemoryBufferSizes().malloc_bytes;
782
783 if (ExternalASTSource *Ext = AST.getExternalSource())
784 Total += Ext->getMemoryBufferSizes().malloc_bytes;
785
786 const Preprocessor &PP = getPreprocessor();
787 Total += PP.getTotalMemory();
788 if (PreprocessingRecord *PRec = PP.getPreprocessingRecord())
789 Total += PRec->getTotalMemory();
790 Total += PP.getHeaderSearchInfo().getTotalMemory();
791
792 return Total;
793}
794
795const IncludeStructure &ParsedAST::getIncludeStructure() const {
796 return Includes;
797}
798
799ParsedAST::ParsedAST(PathRef TUPath, llvm::StringRef Version,
800 std::shared_ptr<const PreambleData> Preamble,
801 std::unique_ptr<CompilerInstance> Clang,
802 std::unique_ptr<FrontendAction> Action,
803 syntax::TokenBuffer Tokens, MainFileMacros Macros,
804 std::vector<PragmaMark> Marks,
805 std::vector<Decl *> LocalTopLevelDecls,
806 std::vector<Diag> Diags, IncludeStructure Includes)
807 : TUPath(TUPath), Version(Version), Preamble(std::move(Preamble)),
808 Clang(std::move(Clang)), Action(std::move(Action)),
809 Tokens(std::move(Tokens)), Macros(std::move(Macros)),
810 Marks(std::move(Marks)), Diags(std::move(Diags)),
811 LocalTopLevelDecls(std::move(LocalTopLevelDecls)),
812 Includes(std::move(Includes)) {
813 Resolver = std::make_unique<HeuristicResolver>(getASTContext());
814 assert(this->Clang);
815 assert(this->Action);
816}
817
818std::shared_ptr<const include_cleaner::PragmaIncludes>
819ParsedAST::getPragmaIncludes() const {
820 if (!Preamble)
821 return nullptr;
822 return Preamble->Pragmas;
823}
824
825std::optional<llvm::StringRef> ParsedAST::preambleVersion() const {
826 if (!Preamble)
827 return std::nullopt;
828 return llvm::StringRef(Preamble->Version);
829}
830
831llvm::ArrayRef<Diag> ParsedAST::getDiagnostics() const { return Diags; }
832} // namespace clangd
833} // namespace clang
834