Bug Summary

File:tools/clang/lib/StaticAnalyzer/Core/PlistDiagnostics.cpp
Warning:line 400, column 21
Called C++ object pointer is null

Annotated Source Code

1//===--- PlistDiagnostics.cpp - Plist Diagnostics for Paths -----*- C++ -*-===//
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 defines the PlistDiagnostics object.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/Basic/FileManager.h"
15#include "clang/Basic/PlistSupport.h"
16#include "clang/Basic/SourceManager.h"
17#include "clang/Basic/Version.h"
18#include "clang/Lex/Preprocessor.h"
19#include "clang/StaticAnalyzer/Core/BugReporter/PathDiagnostic.h"
20#include "clang/StaticAnalyzer/Core/IssueHash.h"
21#include "clang/StaticAnalyzer/Core/PathDiagnosticConsumers.h"
22#include "llvm/ADT/SmallVector.h"
23#include "llvm/Support/Casting.h"
24using namespace clang;
25using namespace ento;
26using namespace markup;
27
28namespace {
29 class PlistDiagnostics : public PathDiagnosticConsumer {
30 const std::string OutputFile;
31 const LangOptions &LangOpts;
32 const bool SupportsCrossFileDiagnostics;
33 public:
34 PlistDiagnostics(AnalyzerOptions &AnalyzerOpts,
35 const std::string& prefix,
36 const LangOptions &LangOpts,
37 bool supportsMultipleFiles);
38
39 ~PlistDiagnostics() override {}
40
41 void FlushDiagnosticsImpl(std::vector<const PathDiagnostic *> &Diags,
42 FilesMade *filesMade) override;
43
44 StringRef getName() const override {
45 return "PlistDiagnostics";
46 }
47
48 PathGenerationScheme getGenerationScheme() const override {
49 return Extensive;
50 }
51 bool supportsLogicalOpControlFlow() const override { return true; }
52 bool supportsCrossFileDiagnostics() const override {
53 return SupportsCrossFileDiagnostics;
54 }
55 };
56} // end anonymous namespace
57
58PlistDiagnostics::PlistDiagnostics(AnalyzerOptions &AnalyzerOpts,
59 const std::string& output,
60 const LangOptions &LO,
61 bool supportsMultipleFiles)
62 : OutputFile(output),
63 LangOpts(LO),
64 SupportsCrossFileDiagnostics(supportsMultipleFiles) {}
65
66void ento::createPlistDiagnosticConsumer(AnalyzerOptions &AnalyzerOpts,
67 PathDiagnosticConsumers &C,
68 const std::string& s,
69 const Preprocessor &PP) {
70 C.push_back(new PlistDiagnostics(AnalyzerOpts, s,
71 PP.getLangOpts(), false));
72}
73
74void ento::createPlistMultiFileDiagnosticConsumer(AnalyzerOptions &AnalyzerOpts,
75 PathDiagnosticConsumers &C,
76 const std::string &s,
77 const Preprocessor &PP) {
78 C.push_back(new PlistDiagnostics(AnalyzerOpts, s,
79 PP.getLangOpts(), true));
80}
81
82static void ReportControlFlow(raw_ostream &o,
83 const PathDiagnosticControlFlowPiece& P,
84 const FIDMap& FM,
85 const SourceManager &SM,
86 const LangOptions &LangOpts,
87 unsigned indent) {
88
89 Indent(o, indent) << "<dict>\n";
90 ++indent;
91
92 Indent(o, indent) << "<key>kind</key><string>control</string>\n";
93
94 // Emit edges.
95 Indent(o, indent) << "<key>edges</key>\n";
96 ++indent;
97 Indent(o, indent) << "<array>\n";
98 ++indent;
99 for (PathDiagnosticControlFlowPiece::const_iterator I=P.begin(), E=P.end();
100 I!=E; ++I) {
101 Indent(o, indent) << "<dict>\n";
102 ++indent;
103
104 // Make the ranges of the start and end point self-consistent with adjacent edges
105 // by forcing to use only the beginning of the range. This simplifies the layout
106 // logic for clients.
107 Indent(o, indent) << "<key>start</key>\n";
108 SourceRange StartEdge(
109 SM.getExpansionLoc(I->getStart().asRange().getBegin()));
110 EmitRange(o, SM, Lexer::getAsCharRange(StartEdge, SM, LangOpts), FM,
111 indent + 1);
112
113 Indent(o, indent) << "<key>end</key>\n";
114 SourceRange EndEdge(SM.getExpansionLoc(I->getEnd().asRange().getBegin()));
115 EmitRange(o, SM, Lexer::getAsCharRange(EndEdge, SM, LangOpts), FM,
116 indent + 1);
117
118 --indent;
119 Indent(o, indent) << "</dict>\n";
120 }
121 --indent;
122 Indent(o, indent) << "</array>\n";
123 --indent;
124
125 // Output any helper text.
126 const auto &s = P.getString();
127 if (!s.empty()) {
128 Indent(o, indent) << "<key>alternate</key>";
129 EmitString(o, s) << '\n';
130 }
131
132 --indent;
133 Indent(o, indent) << "</dict>\n";
134}
135
136static void ReportEvent(raw_ostream &o, const PathDiagnosticPiece& P,
137 const FIDMap& FM,
138 const SourceManager &SM,
139 const LangOptions &LangOpts,
140 unsigned indent,
141 unsigned depth,
142 bool isKeyEvent = false) {
143
144 Indent(o, indent) << "<dict>\n";
145 ++indent;
146
147 Indent(o, indent) << "<key>kind</key><string>event</string>\n";
148
149 if (isKeyEvent) {
150 Indent(o, indent) << "<key>key_event</key><true/>\n";
151 }
152
153 // Output the location.
154 FullSourceLoc L = P.getLocation().asLocation();
155
156 Indent(o, indent) << "<key>location</key>\n";
157 EmitLocation(o, SM, L, FM, indent);
158
159 // Output the ranges (if any).
160 ArrayRef<SourceRange> Ranges = P.getRanges();
161
162 if (!Ranges.empty()) {
163 Indent(o, indent) << "<key>ranges</key>\n";
164 Indent(o, indent) << "<array>\n";
165 ++indent;
166 for (auto &R : Ranges)
167 EmitRange(o, SM,
168 Lexer::getAsCharRange(SM.getExpansionRange(R), SM, LangOpts),
169 FM, indent + 1);
170 --indent;
171 Indent(o, indent) << "</array>\n";
172 }
173
174 // Output the call depth.
175 Indent(o, indent) << "<key>depth</key>";
176 EmitInteger(o, depth) << '\n';
177
178 // Output the text.
179 assert(!P.getString().empty())((!P.getString().empty()) ? static_cast<void> (0) : __assert_fail
("!P.getString().empty()", "/tmp/buildd/llvm-toolchain-snapshot-4.0~svn290870/tools/clang/lib/StaticAnalyzer/Core/PlistDiagnostics.cpp"
, 179, __PRETTY_FUNCTION__));
180 Indent(o, indent) << "<key>extended_message</key>\n";
181 Indent(o, indent);
182 EmitString(o, P.getString()) << '\n';
183
184 // Output the short text.
185 // FIXME: Really use a short string.
186 Indent(o, indent) << "<key>message</key>\n";
187 Indent(o, indent);
188 EmitString(o, P.getString()) << '\n';
189
190 // Finish up.
191 --indent;
192 Indent(o, indent); o << "</dict>\n";
193}
194
195static void ReportPiece(raw_ostream &o,
196 const PathDiagnosticPiece &P,
197 const FIDMap& FM, const SourceManager &SM,
198 const LangOptions &LangOpts,
199 unsigned indent,
200 unsigned depth,
201 bool includeControlFlow,
202 bool isKeyEvent = false);
203
204static void ReportCall(raw_ostream &o,
205 const PathDiagnosticCallPiece &P,
206 const FIDMap& FM, const SourceManager &SM,
207 const LangOptions &LangOpts,
208 unsigned indent,
209 unsigned depth) {
210
211 IntrusiveRefCntPtr<PathDiagnosticEventPiece> callEnter =
212 P.getCallEnterEvent();
213
214 if (callEnter)
215 ReportPiece(o, *callEnter, FM, SM, LangOpts, indent, depth, true,
216 P.isLastInMainSourceFile());
217
218 IntrusiveRefCntPtr<PathDiagnosticEventPiece> callEnterWithinCaller =
219 P.getCallEnterWithinCallerEvent();
220
221 ++depth;
222
223 if (callEnterWithinCaller)
224 ReportPiece(o, *callEnterWithinCaller, FM, SM, LangOpts,
225 indent, depth, true);
226
227 for (PathPieces::const_iterator I = P.path.begin(), E = P.path.end();I!=E;++I)
228 ReportPiece(o, **I, FM, SM, LangOpts, indent, depth, true);
229
230 --depth;
231
232 IntrusiveRefCntPtr<PathDiagnosticEventPiece> callExit =
233 P.getCallExitEvent();
234
235 if (callExit)
236 ReportPiece(o, *callExit, FM, SM, LangOpts, indent, depth, true);
237}
238
239static void ReportMacro(raw_ostream &o,
240 const PathDiagnosticMacroPiece& P,
241 const FIDMap& FM, const SourceManager &SM,
242 const LangOptions &LangOpts,
243 unsigned indent,
244 unsigned depth) {
245
246 for (PathPieces::const_iterator I = P.subPieces.begin(), E=P.subPieces.end();
247 I!=E; ++I) {
248 ReportPiece(o, **I, FM, SM, LangOpts, indent, depth, false);
249 }
250}
251
252static void ReportDiag(raw_ostream &o, const PathDiagnosticPiece& P,
253 const FIDMap& FM, const SourceManager &SM,
254 const LangOptions &LangOpts) {
255 ReportPiece(o, P, FM, SM, LangOpts, 4, 0, true);
256}
257
258static void ReportPiece(raw_ostream &o,
259 const PathDiagnosticPiece &P,
260 const FIDMap& FM, const SourceManager &SM,
261 const LangOptions &LangOpts,
262 unsigned indent,
263 unsigned depth,
264 bool includeControlFlow,
265 bool isKeyEvent) {
266 switch (P.getKind()) {
267 case PathDiagnosticPiece::ControlFlow:
268 if (includeControlFlow)
269 ReportControlFlow(o, cast<PathDiagnosticControlFlowPiece>(P), FM, SM,
270 LangOpts, indent);
271 break;
272 case PathDiagnosticPiece::Call:
273 ReportCall(o, cast<PathDiagnosticCallPiece>(P), FM, SM, LangOpts,
274 indent, depth);
275 break;
276 case PathDiagnosticPiece::Event:
277 ReportEvent(o, cast<PathDiagnosticSpotPiece>(P), FM, SM, LangOpts,
278 indent, depth, isKeyEvent);
279 break;
280 case PathDiagnosticPiece::Macro:
281 ReportMacro(o, cast<PathDiagnosticMacroPiece>(P), FM, SM, LangOpts,
282 indent, depth);
283 break;
284 case PathDiagnosticPiece::Note:
285 // FIXME: Extend the plist format to support those.
286 break;
287 }
288}
289
290void PlistDiagnostics::FlushDiagnosticsImpl(
291 std::vector<const PathDiagnostic *> &Diags,
292 FilesMade *filesMade) {
293 // Build up a set of FIDs that we use by scanning the locations and
294 // ranges of the diagnostics.
295 FIDMap FM;
296 SmallVector<FileID, 10> Fids;
297 const SourceManager* SM = nullptr;
1
'SM' initialized to a null pointer value
→
298
299 if (!Diags.empty())
2
←
Assuming the condition is false
→
3
←
Taking false branch
→
300 SM = &Diags.front()->path.front()->getLocation().getManager();
301
302
303 auto AddPieceFID = [&FM, &Fids, SM](const PathDiagnosticPiece *Piece)->void {
304 AddFID(FM, Fids, *SM, Piece->getLocation().asLocation());
305 ArrayRef<SourceRange> Ranges = Piece->getRanges();
306 for (const SourceRange &Range : Ranges) {
307 AddFID(FM, Fids, *SM, Range.getBegin());
308 AddFID(FM, Fids, *SM, Range.getEnd());
309 }
310 };
311
312 for (const PathDiagnostic *D : Diags) {
313
314 SmallVector<const PathPieces *, 5> WorkList;
315 WorkList.push_back(&D->path);
316
317 while (!WorkList.empty()) {
318 const PathPieces &Path = *WorkList.pop_back_val();
319
320 for (const auto &Iter : Path) {
321 const PathDiagnosticPiece *Piece = Iter.get();
322 AddPieceFID(Piece);
323
324 if (const PathDiagnosticCallPiece *Call =
325 dyn_cast<PathDiagnosticCallPiece>(Piece)) {
326 if (IntrusiveRefCntPtr<PathDiagnosticEventPiece>
327 CallEnterWithin = Call->getCallEnterWithinCallerEvent())
328 AddPieceFID(CallEnterWithin.get());
329
330 if (IntrusiveRefCntPtr<PathDiagnosticEventPiece>
331 CallEnterEvent = Call->getCallEnterEvent())
332 AddPieceFID(CallEnterEvent.get());
333
334 WorkList.push_back(&Call->path);
335 }
336 else if (const PathDiagnosticMacroPiece *Macro =
337 dyn_cast<PathDiagnosticMacroPiece>(Piece)) {
338 WorkList.push_back(&Macro->subPieces);
339 }
340 }
341 }
342 }
343
344 // Open the file.
345 std::error_code EC;
346 llvm::raw_fd_ostream o(OutputFile, EC, llvm::sys::fs::F_Text);
347 if (EC) {
4
←
Taking false branch
→
348 llvm::errs() << "warning: could not create file: " << EC.message() << '\n';
349 return;
350 }
351
352 EmitPlistHeader(o);
353
354 // Write the root object: a <dict> containing...
355 // - "clang_version", the string representation of clang version
356 // - "files", an <array> mapping from FIDs to file names
357 // - "diagnostics", an <array> containing the path diagnostics
358 o << "<dict>\n" <<
359 " <key>clang_version</key>\n";
360 EmitString(o, getClangFullVersion()) << '\n';
361 o << " <key>files</key>\n"
362 " <array>\n";
363
364 for (FileID FID : Fids)
5
←
Assuming '__begin' is equal to '__end'
→
365 EmitString(o << " ", SM->getFileEntryForID(FID)->getName()) << '\n';
366
367 o << " </array>\n"
368 " <key>diagnostics</key>\n"
369 " <array>\n";
370
371 for (std::vector<const PathDiagnostic*>::iterator DI=Diags.begin(),
6
←
Loop condition is true. Entering loop body
→
372 DE = Diags.end(); DI!=DE; ++DI) {
373
374 o << " <dict>\n"
375 " <key>path</key>\n";
376
377 const PathDiagnostic *D = *DI;
378
379 o << " <array>\n";
380
381 for (PathPieces::const_iterator I = D->path.begin(), E = D->path.end();
7
←
Loop condition is false. Execution continues on line 385
→
382 I != E; ++I)
383 ReportDiag(o, **I, FM, *SM, LangOpts);
384
385 o << " </array>\n";
386
387 // Output the bug type and bug category.
388 o << " <key>description</key>";
389 EmitString(o, D->getShortDescription()) << '\n';
390 o << " <key>category</key>";
391 EmitString(o, D->getCategory()) << '\n';
392 o << " <key>type</key>";
393 EmitString(o, D->getBugType()) << '\n';
394 o << " <key>check_name</key>";
395 EmitString(o, D->getCheckName()) << '\n';
396
397 o << " <!-- This hash is experimental and going to change! -->\n";
398 o << " <key>issue_hash_content_of_line_in_context</key>";
399 PathDiagnosticLocation UPDLoc = D->getUniqueingLoc();
400 FullSourceLoc L(SM->getExpansionLoc(UPDLoc.isValid()
8
←
'?' condition is true
→
9
←
Called C++ object pointer is null
401 ? UPDLoc.asLocation()
402 : D->getLocation().asLocation()),
403 *SM);
404 const Decl *DeclWithIssue = D->getDeclWithIssue();
405 EmitString(o, GetIssueHash(*SM, L, D->getCheckName(), D->getBugType(),
406 DeclWithIssue, LangOpts))
407 << '\n';
408
409 // Output information about the semantic context where
410 // the issue occurred.
411 if (const Decl *DeclWithIssue = D->getDeclWithIssue()) {
412 // FIXME: handle blocks, which have no name.
413 if (const NamedDecl *ND = dyn_cast<NamedDecl>(DeclWithIssue)) {
414 StringRef declKind;
415 switch (ND->getKind()) {
416 case Decl::CXXRecord:
417 declKind = "C++ class";
418 break;
419 case Decl::CXXMethod:
420 declKind = "C++ method";
421 break;
422 case Decl::ObjCMethod:
423 declKind = "Objective-C method";
424 break;
425 case Decl::Function:
426 declKind = "function";
427 break;
428 default:
429 break;
430 }
431 if (!declKind.empty()) {
432 const std::string &declName = ND->getDeclName().getAsString();
433 o << " <key>issue_context_kind</key>";
434 EmitString(o, declKind) << '\n';
435 o << " <key>issue_context</key>";
436 EmitString(o, declName) << '\n';
437 }
438
439 // Output the bug hash for issue unique-ing. Currently, it's just an
440 // offset from the beginning of the function.
441 if (const Stmt *Body = DeclWithIssue->getBody()) {
442
443 // If the bug uniqueing location exists, use it for the hash.
444 // For example, this ensures that two leaks reported on the same line
445 // will have different issue_hashes and that the hash will identify
446 // the leak location even after code is added between the allocation
447 // site and the end of scope (leak report location).
448 if (UPDLoc.isValid()) {
449 FullSourceLoc UFunL(SM->getExpansionLoc(
450 D->getUniqueingDecl()->getBody()->getLocStart()), *SM);
451 o << " <key>issue_hash_function_offset</key><string>"
452 << L.getExpansionLineNumber() - UFunL.getExpansionLineNumber()
453 << "</string>\n";
454
455 // Otherwise, use the location on which the bug is reported.
456 } else {
457 FullSourceLoc FunL(SM->getExpansionLoc(Body->getLocStart()), *SM);
458 o << " <key>issue_hash_function_offset</key><string>"
459 << L.getExpansionLineNumber() - FunL.getExpansionLineNumber()
460 << "</string>\n";
461 }
462
463 }
464 }
465 }
466
467 // Output the location of the bug.
468 o << " <key>location</key>\n";
469 EmitLocation(o, *SM, D->getLocation().asLocation(), FM, 2);
470
471 // Output the diagnostic to the sub-diagnostic client, if any.
472 if (!filesMade->empty()) {
473 StringRef lastName;
474 PDFileEntry::ConsumerFiles *files = filesMade->getFiles(*D);
475 if (files) {
476 for (PDFileEntry::ConsumerFiles::const_iterator CI = files->begin(),
477 CE = files->end(); CI != CE; ++CI) {
478 StringRef newName = CI->first;
479 if (newName != lastName) {
480 if (!lastName.empty()) {
481 o << " </array>\n";
482 }
483 lastName = newName;
484 o << " <key>" << lastName << "_files</key>\n";
485 o << " <array>\n";
486 }
487 o << " <string>" << CI->second << "</string>\n";
488 }
489 o << " </array>\n";
490 }
491 }
492
493 // Close up the entry.
494 o << " </dict>\n";
495 }
496
497 o << " </array>\n";
498
499 // Finish.
500 o << "</dict>\n</plist>";
501}