1 //===--- DiagnosticRenderer.cpp - Diagnostic Pretty-Printing --------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "clang/Frontend/DiagnosticRenderer.h"
11 #include "clang/Basic/DiagnosticOptions.h"
12 #include "clang/Basic/FileManager.h"
13 #include "clang/Basic/SourceManager.h"
14 #include "clang/Edit/Commit.h"
15 #include "clang/Edit/EditedSource.h"
16 #include "clang/Edit/EditsReceiver.h"
17 #include "clang/Lex/Lexer.h"
18 #include "llvm/ADT/SmallSet.h"
19 #include "llvm/ADT/SmallString.h"
20 #include "llvm/Support/ErrorHandling.h"
21 #include "llvm/Support/MemoryBuffer.h"
22 #include "llvm/Support/raw_ostream.h"
24 using namespace clang;
26 /// \brief Retrieve the name of the immediate macro expansion.
28 /// This routine starts from a source location, and finds the name of the macro
29 /// responsible for its immediate expansion. It looks through any intervening
30 /// macro argument expansions to compute this. It returns a StringRef which
31 /// refers to the SourceManager-owned buffer of the source where that macro
32 /// name is spelled. Thus, the result shouldn't out-live that SourceManager.
34 /// This differs from Lexer::getImmediateMacroName in that any macro argument
35 /// location will result in the topmost function macro that accepted it.
40 /// for location of 'foo' token, this function will return "MAC1" while
41 /// Lexer::getImmediateMacroName will return "MAC2".
42 static StringRef getImmediateMacroName(SourceLocation Loc,
43 const SourceManager &SM,
44 const LangOptions &LangOpts) {
45 assert(Loc.isMacroID() && "Only reasonble to call this on macros");
46 // Walk past macro argument expanions.
47 while (SM.isMacroArgExpansion(Loc))
48 Loc = SM.getImmediateExpansionRange(Loc).first;
50 // If the macro's spelling has no FileID, then it's actually a token paste
51 // or stringization (or similar) and not a macro at all.
52 if (!SM.getFileEntryForID(SM.getFileID(SM.getSpellingLoc(Loc))))
55 // Find the spelling location of the start of the non-argument expansion
56 // range. This is where the macro name was spelled in order to begin
57 // expanding this macro.
58 Loc = SM.getSpellingLoc(SM.getImmediateExpansionRange(Loc).first);
60 // Dig out the buffer where the macro name was spelled and the extents of the
61 // name so that we can render it into the expansion note.
62 std::pair<FileID, unsigned> ExpansionInfo = SM.getDecomposedLoc(Loc);
63 unsigned MacroTokenLength = Lexer::MeasureTokenLength(Loc, SM, LangOpts);
64 StringRef ExpansionBuffer = SM.getBufferData(ExpansionInfo.first);
65 return ExpansionBuffer.substr(ExpansionInfo.second, MacroTokenLength);
68 DiagnosticRenderer::DiagnosticRenderer(const LangOptions &LangOpts,
69 DiagnosticOptions *DiagOpts)
70 : LangOpts(LangOpts), DiagOpts(DiagOpts), LastLevel() {}
72 DiagnosticRenderer::~DiagnosticRenderer() {}
76 class FixitReceiver : public edit::EditsReceiver {
77 SmallVectorImpl<FixItHint> &MergedFixits;
80 FixitReceiver(SmallVectorImpl<FixItHint> &MergedFixits)
81 : MergedFixits(MergedFixits) { }
82 virtual void insert(SourceLocation loc, StringRef text) {
83 MergedFixits.push_back(FixItHint::CreateInsertion(loc, text));
85 virtual void replace(CharSourceRange range, StringRef text) {
86 MergedFixits.push_back(FixItHint::CreateReplacement(range, text));
92 static void mergeFixits(ArrayRef<FixItHint> FixItHints,
93 const SourceManager &SM, const LangOptions &LangOpts,
94 SmallVectorImpl<FixItHint> &MergedFixits) {
95 edit::Commit commit(SM, LangOpts);
96 for (ArrayRef<FixItHint>::const_iterator
97 I = FixItHints.begin(), E = FixItHints.end(); I != E; ++I) {
98 const FixItHint &Hint = *I;
99 if (Hint.CodeToInsert.empty()) {
100 if (Hint.InsertFromRange.isValid())
101 commit.insertFromRange(Hint.RemoveRange.getBegin(),
102 Hint.InsertFromRange, /*afterToken=*/false,
103 Hint.BeforePreviousInsertions);
105 commit.remove(Hint.RemoveRange);
107 if (Hint.RemoveRange.isTokenRange() ||
108 Hint.RemoveRange.getBegin() != Hint.RemoveRange.getEnd())
109 commit.replace(Hint.RemoveRange, Hint.CodeToInsert);
111 commit.insert(Hint.RemoveRange.getBegin(), Hint.CodeToInsert,
112 /*afterToken=*/false, Hint.BeforePreviousInsertions);
116 edit::EditedSource Editor(SM, LangOpts);
117 if (Editor.commit(commit)) {
118 FixitReceiver Rec(MergedFixits);
119 Editor.applyRewrites(Rec);
123 void DiagnosticRenderer::emitDiagnostic(SourceLocation Loc,
124 DiagnosticsEngine::Level Level,
126 ArrayRef<CharSourceRange> Ranges,
127 ArrayRef<FixItHint> FixItHints,
128 const SourceManager *SM,
129 DiagOrStoredDiag D) {
130 assert(SM || Loc.isInvalid());
132 beginDiagnostic(D, Level);
135 // If we have no source location, just emit the diagnostic message.
136 emitDiagnosticMessage(Loc, PresumedLoc(), Level, Message, Ranges, SM, D);
138 // Get the ranges into a local array we can hack on.
139 SmallVector<CharSourceRange, 20> MutableRanges(Ranges.begin(),
142 SmallVector<FixItHint, 8> MergedFixits;
143 if (!FixItHints.empty()) {
144 mergeFixits(FixItHints, *SM, LangOpts, MergedFixits);
145 FixItHints = MergedFixits;
148 for (ArrayRef<FixItHint>::const_iterator I = FixItHints.begin(),
149 E = FixItHints.end();
151 if (I->RemoveRange.isValid())
152 MutableRanges.push_back(I->RemoveRange);
154 SourceLocation UnexpandedLoc = Loc;
156 // Find the ultimate expansion location for the diagnostic.
157 Loc = SM->getFileLoc(Loc);
159 PresumedLoc PLoc = SM->getPresumedLoc(Loc, DiagOpts->ShowPresumedLoc);
161 // First, if this diagnostic is not in the main file, print out the
162 // "included from" lines.
163 emitIncludeStack(Loc, PLoc, Level, *SM);
165 // Next, emit the actual diagnostic message and caret.
166 emitDiagnosticMessage(Loc, PLoc, Level, Message, Ranges, SM, D);
167 emitCaret(Loc, Level, MutableRanges, FixItHints, *SM);
169 // If this location is within a macro, walk from UnexpandedLoc up to Loc
170 // and produce a macro backtrace.
171 if (UnexpandedLoc.isValid() && UnexpandedLoc.isMacroID()) {
172 unsigned MacroDepth = 0;
173 emitMacroExpansions(UnexpandedLoc, Level, MutableRanges, FixItHints, *SM,
181 endDiagnostic(D, Level);
185 void DiagnosticRenderer::emitStoredDiagnostic(StoredDiagnostic &Diag) {
186 emitDiagnostic(Diag.getLocation(), Diag.getLevel(), Diag.getMessage(),
187 Diag.getRanges(), Diag.getFixIts(),
188 Diag.getLocation().isValid() ? &Diag.getLocation().getManager()
193 /// \brief Prints an include stack when appropriate for a particular
194 /// diagnostic level and location.
196 /// This routine handles all the logic of suppressing particular include
197 /// stacks (such as those for notes) and duplicate include stacks when
198 /// repeated warnings occur within the same file. It also handles the logic
199 /// of customizing the formatting and display of the include stack.
201 /// \param Loc The diagnostic location.
202 /// \param PLoc The presumed location of the diagnostic location.
203 /// \param Level The diagnostic level of the message this stack pertains to.
204 void DiagnosticRenderer::emitIncludeStack(SourceLocation Loc,
206 DiagnosticsEngine::Level Level,
207 const SourceManager &SM) {
208 SourceLocation IncludeLoc = PLoc.getIncludeLoc();
210 // Skip redundant include stacks altogether.
211 if (LastIncludeLoc == IncludeLoc)
214 LastIncludeLoc = IncludeLoc;
216 if (!DiagOpts->ShowNoteIncludeStack && Level == DiagnosticsEngine::Note)
219 if (IncludeLoc.isValid())
220 emitIncludeStackRecursively(IncludeLoc, SM);
222 emitModuleBuildStack(SM);
223 emitImportStack(Loc, SM);
227 /// \brief Helper to recursivly walk up the include stack and print each layer
228 /// on the way back down.
229 void DiagnosticRenderer::emitIncludeStackRecursively(SourceLocation Loc,
230 const SourceManager &SM) {
231 if (Loc.isInvalid()) {
232 emitModuleBuildStack(SM);
236 PresumedLoc PLoc = SM.getPresumedLoc(Loc, DiagOpts->ShowPresumedLoc);
237 if (PLoc.isInvalid())
240 // If this source location was imported from a module, print the module
241 // import stack rather than the
242 // FIXME: We want submodule granularity here.
243 std::pair<SourceLocation, StringRef> Imported = SM.getModuleImportLoc(Loc);
244 if (Imported.first.isValid()) {
245 // This location was imported by a module. Emit the module import stack.
246 emitImportStackRecursively(Imported.first, Imported.second, SM);
250 // Emit the other include frames first.
251 emitIncludeStackRecursively(PLoc.getIncludeLoc(), SM);
253 // Emit the inclusion text/note.
254 emitIncludeLocation(Loc, PLoc, SM);
257 /// \brief Emit the module import stack associated with the current location.
258 void DiagnosticRenderer::emitImportStack(SourceLocation Loc,
259 const SourceManager &SM) {
260 if (Loc.isInvalid()) {
261 emitModuleBuildStack(SM);
265 std::pair<SourceLocation, StringRef> NextImportLoc
266 = SM.getModuleImportLoc(Loc);
267 emitImportStackRecursively(NextImportLoc.first, NextImportLoc.second, SM);
270 /// \brief Helper to recursivly walk up the import stack and print each layer
271 /// on the way back down.
272 void DiagnosticRenderer::emitImportStackRecursively(SourceLocation Loc,
273 StringRef ModuleName,
274 const SourceManager &SM) {
275 if (Loc.isInvalid()) {
279 PresumedLoc PLoc = SM.getPresumedLoc(Loc, DiagOpts->ShowPresumedLoc);
280 if (PLoc.isInvalid())
283 // Emit the other import frames first.
284 std::pair<SourceLocation, StringRef> NextImportLoc
285 = SM.getModuleImportLoc(Loc);
286 emitImportStackRecursively(NextImportLoc.first, NextImportLoc.second, SM);
288 // Emit the inclusion text/note.
289 emitImportLocation(Loc, PLoc, ModuleName, SM);
292 /// \brief Emit the module build stack, for cases where a module is (re-)built
294 void DiagnosticRenderer::emitModuleBuildStack(const SourceManager &SM) {
295 ModuleBuildStack Stack = SM.getModuleBuildStack();
296 for (unsigned I = 0, N = Stack.size(); I != N; ++I) {
297 const SourceManager &CurSM = Stack[I].second.getManager();
298 SourceLocation CurLoc = Stack[I].second;
299 emitBuildingModuleLocation(CurLoc,
300 CurSM.getPresumedLoc(CurLoc,
301 DiagOpts->ShowPresumedLoc),
307 // Helper function to fix up source ranges. It takes in an array of ranges,
308 // and outputs an array of ranges where we want to draw the range highlighting
309 // around the location specified by CaretLoc.
311 // To find locations which correspond to the caret, we crawl the macro caller
312 // chain for the beginning and end of each range. If the caret location
313 // is in a macro expansion, we search each chain for a location
314 // in the same expansion as the caret; otherwise, we crawl to the top of
315 // each chain. Two locations are part of the same macro expansion
316 // iff the FileID is the same.
317 static void mapDiagnosticRanges(
318 SourceLocation CaretLoc,
319 ArrayRef<CharSourceRange> Ranges,
320 SmallVectorImpl<CharSourceRange> &SpellingRanges,
321 const SourceManager *SM) {
322 FileID CaretLocFileID = SM->getFileID(CaretLoc);
324 for (ArrayRef<CharSourceRange>::const_iterator I = Ranges.begin(),
327 SourceLocation Begin = I->getBegin(), End = I->getEnd();
328 bool IsTokenRange = I->isTokenRange();
330 FileID BeginFileID = SM->getFileID(Begin);
331 FileID EndFileID = SM->getFileID(End);
333 // Find the common parent for the beginning and end of the range.
335 // First, crawl the expansion chain for the beginning of the range.
336 llvm::SmallDenseMap<FileID, SourceLocation> BeginLocsMap;
337 while (Begin.isMacroID() && BeginFileID != EndFileID) {
338 BeginLocsMap[BeginFileID] = Begin;
339 Begin = SM->getImmediateExpansionRange(Begin).first;
340 BeginFileID = SM->getFileID(Begin);
343 // Then, crawl the expansion chain for the end of the range.
344 if (BeginFileID != EndFileID) {
345 while (End.isMacroID() && !BeginLocsMap.count(EndFileID)) {
346 End = SM->getImmediateExpansionRange(End).second;
347 EndFileID = SM->getFileID(End);
349 if (End.isMacroID()) {
350 Begin = BeginLocsMap[EndFileID];
351 BeginFileID = EndFileID;
355 while (Begin.isMacroID() && BeginFileID != CaretLocFileID) {
356 if (SM->isMacroArgExpansion(Begin)) {
357 Begin = SM->getImmediateSpellingLoc(Begin);
358 End = SM->getImmediateSpellingLoc(End);
360 Begin = SM->getImmediateExpansionRange(Begin).first;
361 End = SM->getImmediateExpansionRange(End).second;
363 BeginFileID = SM->getFileID(Begin);
364 if (BeginFileID != SM->getFileID(End)) {
365 // FIXME: Ugly hack to stop a crash; this code is making bad
366 // assumptions and it's too complicated for me to reason
368 Begin = End = SourceLocation();
373 // Return the spelling location of the beginning and end of the range.
374 Begin = SM->getSpellingLoc(Begin);
375 End = SM->getSpellingLoc(End);
376 SpellingRanges.push_back(CharSourceRange(SourceRange(Begin, End),
381 void DiagnosticRenderer::emitCaret(SourceLocation Loc,
382 DiagnosticsEngine::Level Level,
383 ArrayRef<CharSourceRange> Ranges,
384 ArrayRef<FixItHint> Hints,
385 const SourceManager &SM) {
386 SmallVector<CharSourceRange, 4> SpellingRanges;
387 mapDiagnosticRanges(Loc, Ranges, SpellingRanges, &SM);
388 emitCodeContext(Loc, Level, SpellingRanges, Hints, SM);
391 /// \brief Recursively emit notes for each macro expansion and caret
392 /// diagnostics where appropriate.
394 /// Walks up the macro expansion stack printing expansion notes, the code
395 /// snippet, caret, underlines and FixItHint display as appropriate at each
398 /// \param Loc The location for this caret.
399 /// \param Level The diagnostic level currently being emitted.
400 /// \param Ranges The underlined ranges for this code snippet.
401 /// \param Hints The FixIt hints active for this diagnostic.
402 /// \param OnMacroInst The current depth of the macro expansion stack.
403 void DiagnosticRenderer::emitMacroExpansions(SourceLocation Loc,
404 DiagnosticsEngine::Level Level,
405 ArrayRef<CharSourceRange> Ranges,
406 ArrayRef<FixItHint> Hints,
407 const SourceManager &SM,
408 unsigned &MacroDepth,
409 unsigned OnMacroInst) {
410 assert(!Loc.isInvalid() && "must have a valid source location here");
412 // Walk up to the caller of this macro, and produce a backtrace down to there.
413 SourceLocation OneLevelUp = SM.getImmediateMacroCallerLoc(Loc);
414 if (OneLevelUp.isMacroID())
415 emitMacroExpansions(OneLevelUp, Level, Ranges, Hints, SM,
416 MacroDepth, OnMacroInst + 1);
418 MacroDepth = OnMacroInst + 1;
420 unsigned MacroSkipStart = 0, MacroSkipEnd = 0;
421 if (MacroDepth > DiagOpts->MacroBacktraceLimit &&
422 DiagOpts->MacroBacktraceLimit != 0) {
423 MacroSkipStart = DiagOpts->MacroBacktraceLimit / 2 +
424 DiagOpts->MacroBacktraceLimit % 2;
425 MacroSkipEnd = MacroDepth - DiagOpts->MacroBacktraceLimit / 2;
428 // Whether to suppress printing this macro expansion.
429 bool Suppressed = (OnMacroInst >= MacroSkipStart &&
430 OnMacroInst < MacroSkipEnd);
433 // Tell the user that we've skipped contexts.
434 if (OnMacroInst == MacroSkipStart) {
435 SmallString<200> MessageStorage;
436 llvm::raw_svector_ostream Message(MessageStorage);
437 Message << "(skipping " << (MacroSkipEnd - MacroSkipStart)
438 << " expansions in backtrace; use -fmacro-backtrace-limit=0 to "
440 emitBasicNote(Message.str());
445 // Find the spelling location for the macro definition. We must use the
446 // spelling location here to avoid emitting a macro bactrace for the note.
447 SourceLocation SpellingLoc = Loc;
448 // If this is the expansion of a macro argument, point the caret at the
449 // use of the argument in the definition of the macro, not the expansion.
450 if (SM.isMacroArgExpansion(Loc))
451 SpellingLoc = SM.getImmediateExpansionRange(Loc).first;
452 SpellingLoc = SM.getSpellingLoc(SpellingLoc);
454 // Map the ranges into the FileID of the diagnostic location.
455 SmallVector<CharSourceRange, 4> SpellingRanges;
456 mapDiagnosticRanges(Loc, Ranges, SpellingRanges, &SM);
458 SmallString<100> MessageStorage;
459 llvm::raw_svector_ostream Message(MessageStorage);
460 StringRef MacroName = getImmediateMacroName(Loc, SM, LangOpts);
461 if (MacroName.empty())
462 Message << "expanded from here";
464 Message << "expanded from macro '" << MacroName << "'";
465 emitDiagnostic(SpellingLoc, DiagnosticsEngine::Note, Message.str(),
466 SpellingRanges, None, &SM);
469 DiagnosticNoteRenderer::~DiagnosticNoteRenderer() {}
471 void DiagnosticNoteRenderer::emitIncludeLocation(SourceLocation Loc,
473 const SourceManager &SM) {
474 // Generate a note indicating the include location.
475 SmallString<200> MessageStorage;
476 llvm::raw_svector_ostream Message(MessageStorage);
477 Message << "in file included from " << PLoc.getFilename() << ':'
478 << PLoc.getLine() << ":";
479 emitNote(Loc, Message.str(), &SM);
482 void DiagnosticNoteRenderer::emitImportLocation(SourceLocation Loc,
484 StringRef ModuleName,
485 const SourceManager &SM) {
486 // Generate a note indicating the include location.
487 SmallString<200> MessageStorage;
488 llvm::raw_svector_ostream Message(MessageStorage);
489 Message << "in module '" << ModuleName << "' imported from "
490 << PLoc.getFilename() << ':' << PLoc.getLine() << ":";
491 emitNote(Loc, Message.str(), &SM);
495 DiagnosticNoteRenderer::emitBuildingModuleLocation(SourceLocation Loc,
497 StringRef ModuleName,
498 const SourceManager &SM) {
499 // Generate a note indicating the include location.
500 SmallString<200> MessageStorage;
501 llvm::raw_svector_ostream Message(MessageStorage);
502 Message << "while building module '" << ModuleName << "' imported from "
503 << PLoc.getFilename() << ':' << PLoc.getLine() << ":";
504 emitNote(Loc, Message.str(), &SM);
508 void DiagnosticNoteRenderer::emitBasicNote(StringRef Message) {
509 emitNote(SourceLocation(), Message, 0);