clang  14.0.0git
JumpDiagnostics.cpp
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1 //===--- JumpDiagnostics.cpp - Protected scope jump analysis ------*- 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 // This file implements the JumpScopeChecker class, which is used to diagnose
10 // jumps that enter a protected scope in an invalid way.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #include "clang/AST/DeclCXX.h"
15 #include "clang/AST/Expr.h"
16 #include "clang/AST/ExprCXX.h"
17 #include "clang/AST/StmtCXX.h"
18 #include "clang/AST/StmtObjC.h"
19 #include "clang/AST/StmtOpenMP.h"
22 #include "llvm/ADT/BitVector.h"
23 using namespace clang;
24 
25 namespace {
26 
27 /// JumpScopeChecker - This object is used by Sema to diagnose invalid jumps
28 /// into VLA and other protected scopes. For example, this rejects:
29 /// goto L;
30 /// int a[n];
31 /// L:
32 ///
33 /// We also detect jumps out of protected scopes when it's not possible to do
34 /// cleanups properly. Indirect jumps and ASM jumps can't do cleanups because
35 /// the target is unknown. Return statements with \c [[clang::musttail]] cannot
36 /// handle any cleanups due to the nature of a tail call.
37 class JumpScopeChecker {
38  Sema &S;
39 
40  /// Permissive - True when recovering from errors, in which case precautions
41  /// are taken to handle incomplete scope information.
42  const bool Permissive;
43 
44  /// GotoScope - This is a record that we use to keep track of all of the
45  /// scopes that are introduced by VLAs and other things that scope jumps like
46  /// gotos. This scope tree has nothing to do with the source scope tree,
47  /// because you can have multiple VLA scopes per compound statement, and most
48  /// compound statements don't introduce any scopes.
49  struct GotoScope {
50  /// ParentScope - The index in ScopeMap of the parent scope. This is 0 for
51  /// the parent scope is the function body.
52  unsigned ParentScope;
53 
54  /// InDiag - The note to emit if there is a jump into this scope.
55  unsigned InDiag;
56 
57  /// OutDiag - The note to emit if there is an indirect jump out
58  /// of this scope. Direct jumps always clean up their current scope
59  /// in an orderly way.
60  unsigned OutDiag;
61 
62  /// Loc - Location to emit the diagnostic.
63  SourceLocation Loc;
64 
65  GotoScope(unsigned parentScope, unsigned InDiag, unsigned OutDiag,
67  : ParentScope(parentScope), InDiag(InDiag), OutDiag(OutDiag), Loc(L) {}
68  };
69 
71  llvm::DenseMap<Stmt*, unsigned> LabelAndGotoScopes;
73 
74  SmallVector<Stmt*, 4> IndirectJumps;
75  SmallVector<Stmt*, 4> AsmJumps;
77  SmallVector<LabelDecl*, 4> IndirectJumpTargets;
78  SmallVector<LabelDecl*, 4> AsmJumpTargets;
79 public:
80  JumpScopeChecker(Stmt *Body, Sema &S);
81 private:
82  void BuildScopeInformation(Decl *D, unsigned &ParentScope);
83  void BuildScopeInformation(VarDecl *D, const BlockDecl *BDecl,
84  unsigned &ParentScope);
85  void BuildScopeInformation(CompoundLiteralExpr *CLE, unsigned &ParentScope);
86  void BuildScopeInformation(Stmt *S, unsigned &origParentScope);
87 
88  void VerifyJumps();
89  void VerifyIndirectOrAsmJumps(bool IsAsmGoto);
90  void VerifyMustTailStmts();
91  void NoteJumpIntoScopes(ArrayRef<unsigned> ToScopes);
92  void DiagnoseIndirectOrAsmJump(Stmt *IG, unsigned IGScope, LabelDecl *Target,
93  unsigned TargetScope);
94  void CheckJump(Stmt *From, Stmt *To, SourceLocation DiagLoc,
95  unsigned JumpDiag, unsigned JumpDiagWarning,
96  unsigned JumpDiagCXX98Compat);
97  void CheckGotoStmt(GotoStmt *GS);
98  const Attr *GetMustTailAttr(AttributedStmt *AS);
99 
100  unsigned GetDeepestCommonScope(unsigned A, unsigned B);
101 };
102 } // end anonymous namespace
103 
104 #define CHECK_PERMISSIVE(x) (assert(Permissive || !(x)), (Permissive && (x)))
105 
106 JumpScopeChecker::JumpScopeChecker(Stmt *Body, Sema &s)
107  : S(s), Permissive(s.hasAnyUnrecoverableErrorsInThisFunction()) {
108  // Add a scope entry for function scope.
109  Scopes.push_back(GotoScope(~0U, ~0U, ~0U, SourceLocation()));
110 
111  // Build information for the top level compound statement, so that we have a
112  // defined scope record for every "goto" and label.
113  unsigned BodyParentScope = 0;
114  BuildScopeInformation(Body, BodyParentScope);
115 
116  // Check that all jumps we saw are kosher.
117  VerifyJumps();
118  VerifyIndirectOrAsmJumps(false);
119  VerifyIndirectOrAsmJumps(true);
120  VerifyMustTailStmts();
121 }
122 
123 /// GetDeepestCommonScope - Finds the innermost scope enclosing the
124 /// two scopes.
125 unsigned JumpScopeChecker::GetDeepestCommonScope(unsigned A, unsigned B) {
126  while (A != B) {
127  // Inner scopes are created after outer scopes and therefore have
128  // higher indices.
129  if (A < B) {
130  assert(Scopes[B].ParentScope < B);
131  B = Scopes[B].ParentScope;
132  } else {
133  assert(Scopes[A].ParentScope < A);
134  A = Scopes[A].ParentScope;
135  }
136  }
137  return A;
138 }
139 
140 typedef std::pair<unsigned,unsigned> ScopePair;
141 
142 /// GetDiagForGotoScopeDecl - If this decl induces a new goto scope, return a
143 /// diagnostic that should be emitted if control goes over it. If not, return 0.
145  if (const VarDecl *VD = dyn_cast<VarDecl>(D)) {
146  unsigned InDiag = 0;
147  unsigned OutDiag = 0;
148 
149  if (VD->getType()->isVariablyModifiedType())
150  InDiag = diag::note_protected_by_vla;
151 
152  if (VD->hasAttr<BlocksAttr>())
153  return ScopePair(diag::note_protected_by___block,
154  diag::note_exits___block);
155 
156  if (VD->hasAttr<CleanupAttr>())
157  return ScopePair(diag::note_protected_by_cleanup,
158  diag::note_exits_cleanup);
159 
160  if (VD->hasLocalStorage()) {
161  switch (VD->getType().isDestructedType()) {
162  case QualType::DK_objc_strong_lifetime:
163  return ScopePair(diag::note_protected_by_objc_strong_init,
164  diag::note_exits_objc_strong);
165 
166  case QualType::DK_objc_weak_lifetime:
167  return ScopePair(diag::note_protected_by_objc_weak_init,
168  diag::note_exits_objc_weak);
169 
170  case QualType::DK_nontrivial_c_struct:
171  return ScopePair(diag::note_protected_by_non_trivial_c_struct_init,
172  diag::note_exits_dtor);
173 
174  case QualType::DK_cxx_destructor:
175  OutDiag = diag::note_exits_dtor;
176  break;
177 
178  case QualType::DK_none:
179  break;
180  }
181  }
182 
183  const Expr *Init = VD->getInit();
184  if (S.Context.getLangOpts().CPlusPlus && VD->hasLocalStorage() && Init) {
185  // C++11 [stmt.dcl]p3:
186  // A program that jumps from a point where a variable with automatic
187  // storage duration is not in scope to a point where it is in scope
188  // is ill-formed unless the variable has scalar type, class type with
189  // a trivial default constructor and a trivial destructor, a
190  // cv-qualified version of one of these types, or an array of one of
191  // the preceding types and is declared without an initializer.
192 
193  // C++03 [stmt.dcl.p3:
194  // A program that jumps from a point where a local variable
195  // with automatic storage duration is not in scope to a point
196  // where it is in scope is ill-formed unless the variable has
197  // POD type and is declared without an initializer.
198 
199  InDiag = diag::note_protected_by_variable_init;
200 
201  // For a variable of (array of) class type declared without an
202  // initializer, we will have call-style initialization and the initializer
203  // will be the CXXConstructExpr with no intervening nodes.
204  if (const CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init)) {
205  const CXXConstructorDecl *Ctor = CCE->getConstructor();
206  if (Ctor->isTrivial() && Ctor->isDefaultConstructor() &&
207  VD->getInitStyle() == VarDecl::CallInit) {
208  if (OutDiag)
209  InDiag = diag::note_protected_by_variable_nontriv_destructor;
210  else if (!Ctor->getParent()->isPOD())
211  InDiag = diag::note_protected_by_variable_non_pod;
212  else
213  InDiag = 0;
214  }
215  }
216  }
217 
218  return ScopePair(InDiag, OutDiag);
219  }
220 
221  if (const TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(D)) {
222  if (TD->getUnderlyingType()->isVariablyModifiedType())
223  return ScopePair(isa<TypedefDecl>(TD)
224  ? diag::note_protected_by_vla_typedef
225  : diag::note_protected_by_vla_type_alias,
226  0);
227  }
228 
229  return ScopePair(0U, 0U);
230 }
231 
232 /// Build scope information for a declaration that is part of a DeclStmt.
233 void JumpScopeChecker::BuildScopeInformation(Decl *D, unsigned &ParentScope) {
234  // If this decl causes a new scope, push and switch to it.
235  std::pair<unsigned,unsigned> Diags = GetDiagForGotoScopeDecl(S, D);
236  if (Diags.first || Diags.second) {
237  Scopes.push_back(GotoScope(ParentScope, Diags.first, Diags.second,
238  D->getLocation()));
239  ParentScope = Scopes.size()-1;
240  }
241 
242  // If the decl has an initializer, walk it with the potentially new
243  // scope we just installed.
244  if (VarDecl *VD = dyn_cast<VarDecl>(D))
245  if (Expr *Init = VD->getInit())
246  BuildScopeInformation(Init, ParentScope);
247 }
248 
249 /// Build scope information for a captured block literal variables.
250 void JumpScopeChecker::BuildScopeInformation(VarDecl *D,
251  const BlockDecl *BDecl,
252  unsigned &ParentScope) {
253  // exclude captured __block variables; there's no destructor
254  // associated with the block literal for them.
255  if (D->hasAttr<BlocksAttr>())
256  return;
257  QualType T = D->getType();
258  QualType::DestructionKind destructKind = T.isDestructedType();
259  if (destructKind != QualType::DK_none) {
260  std::pair<unsigned,unsigned> Diags;
261  switch (destructKind) {
262  case QualType::DK_cxx_destructor:
263  Diags = ScopePair(diag::note_enters_block_captures_cxx_obj,
264  diag::note_exits_block_captures_cxx_obj);
265  break;
266  case QualType::DK_objc_strong_lifetime:
267  Diags = ScopePair(diag::note_enters_block_captures_strong,
268  diag::note_exits_block_captures_strong);
269  break;
270  case QualType::DK_objc_weak_lifetime:
271  Diags = ScopePair(diag::note_enters_block_captures_weak,
272  diag::note_exits_block_captures_weak);
273  break;
274  case QualType::DK_nontrivial_c_struct:
275  Diags = ScopePair(diag::note_enters_block_captures_non_trivial_c_struct,
276  diag::note_exits_block_captures_non_trivial_c_struct);
277  break;
278  case QualType::DK_none:
279  llvm_unreachable("non-lifetime captured variable");
280  }
281  SourceLocation Loc = D->getLocation();
282  if (Loc.isInvalid())
283  Loc = BDecl->getLocation();
284  Scopes.push_back(GotoScope(ParentScope,
285  Diags.first, Diags.second, Loc));
286  ParentScope = Scopes.size()-1;
287  }
288 }
289 
290 /// Build scope information for compound literals of C struct types that are
291 /// non-trivial to destruct.
292 void JumpScopeChecker::BuildScopeInformation(CompoundLiteralExpr *CLE,
293  unsigned &ParentScope) {
294  unsigned InDiag = diag::note_enters_compound_literal_scope;
295  unsigned OutDiag = diag::note_exits_compound_literal_scope;
296  Scopes.push_back(GotoScope(ParentScope, InDiag, OutDiag, CLE->getExprLoc()));
297  ParentScope = Scopes.size() - 1;
298 }
299 
300 /// BuildScopeInformation - The statements from CI to CE are known to form a
301 /// coherent VLA scope with a specified parent node. Walk through the
302 /// statements, adding any labels or gotos to LabelAndGotoScopes and recursively
303 /// walking the AST as needed.
304 void JumpScopeChecker::BuildScopeInformation(Stmt *S,
305  unsigned &origParentScope) {
306  // If this is a statement, rather than an expression, scopes within it don't
307  // propagate out into the enclosing scope. Otherwise we have to worry
308  // about block literals, which have the lifetime of their enclosing statement.
309  unsigned independentParentScope = origParentScope;
310  unsigned &ParentScope = ((isa<Expr>(S) && !isa<StmtExpr>(S))
311  ? origParentScope : independentParentScope);
312 
313  unsigned StmtsToSkip = 0u;
314 
315  // If we found a label, remember that it is in ParentScope scope.
316  switch (S->getStmtClass()) {
317  case Stmt::AddrLabelExprClass:
318  IndirectJumpTargets.push_back(cast<AddrLabelExpr>(S)->getLabel());
319  break;
320 
321  case Stmt::ObjCForCollectionStmtClass: {
322  auto *CS = cast<ObjCForCollectionStmt>(S);
323  unsigned Diag = diag::note_protected_by_objc_fast_enumeration;
324  unsigned NewParentScope = Scopes.size();
325  Scopes.push_back(GotoScope(ParentScope, Diag, 0, S->getBeginLoc()));
326  BuildScopeInformation(CS->getBody(), NewParentScope);
327  return;
328  }
329 
330  case Stmt::IndirectGotoStmtClass:
331  // "goto *&&lbl;" is a special case which we treat as equivalent
332  // to a normal goto. In addition, we don't calculate scope in the
333  // operand (to avoid recording the address-of-label use), which
334  // works only because of the restricted set of expressions which
335  // we detect as constant targets.
336  if (cast<IndirectGotoStmt>(S)->getConstantTarget()) {
337  LabelAndGotoScopes[S] = ParentScope;
338  Jumps.push_back(S);
339  return;
340  }
341 
342  LabelAndGotoScopes[S] = ParentScope;
343  IndirectJumps.push_back(S);
344  break;
345 
346  case Stmt::SwitchStmtClass:
347  // Evaluate the C++17 init stmt and condition variable
348  // before entering the scope of the switch statement.
349  if (Stmt *Init = cast<SwitchStmt>(S)->getInit()) {
350  BuildScopeInformation(Init, ParentScope);
351  ++StmtsToSkip;
352  }
353  if (VarDecl *Var = cast<SwitchStmt>(S)->getConditionVariable()) {
354  BuildScopeInformation(Var, ParentScope);
355  ++StmtsToSkip;
356  }
357  LLVM_FALLTHROUGH;
358 
359  case Stmt::GotoStmtClass:
360  // Remember both what scope a goto is in as well as the fact that we have
361  // it. This makes the second scan not have to walk the AST again.
362  LabelAndGotoScopes[S] = ParentScope;
363  Jumps.push_back(S);
364  break;
365 
366  case Stmt::GCCAsmStmtClass:
367  if (auto *GS = dyn_cast<GCCAsmStmt>(S))
368  if (GS->isAsmGoto()) {
369  // Remember both what scope a goto is in as well as the fact that we
370  // have it. This makes the second scan not have to walk the AST again.
371  LabelAndGotoScopes[S] = ParentScope;
372  AsmJumps.push_back(GS);
373  for (auto *E : GS->labels())
374  AsmJumpTargets.push_back(E->getLabel());
375  }
376  break;
377 
378  case Stmt::IfStmtClass: {
379  IfStmt *IS = cast<IfStmt>(S);
380  if (!(IS->isConstexpr() || IS->isConsteval() ||
382  break;
383 
384  unsigned Diag = diag::note_protected_by_if_available;
385  if (IS->isConstexpr())
386  Diag = diag::note_protected_by_constexpr_if;
387  else if (IS->isConsteval())
388  Diag = diag::note_protected_by_consteval_if;
389 
390  if (VarDecl *Var = IS->getConditionVariable())
391  BuildScopeInformation(Var, ParentScope);
392 
393  // Cannot jump into the middle of the condition.
394  unsigned NewParentScope = Scopes.size();
395  Scopes.push_back(GotoScope(ParentScope, Diag, 0, IS->getBeginLoc()));
396 
397  if (!IS->isConsteval())
398  BuildScopeInformation(IS->getCond(), NewParentScope);
399 
400  // Jumps into either arm of an 'if constexpr' are not allowed.
401  NewParentScope = Scopes.size();
402  Scopes.push_back(GotoScope(ParentScope, Diag, 0, IS->getBeginLoc()));
403  BuildScopeInformation(IS->getThen(), NewParentScope);
404  if (Stmt *Else = IS->getElse()) {
405  NewParentScope = Scopes.size();
406  Scopes.push_back(GotoScope(ParentScope, Diag, 0, IS->getBeginLoc()));
407  BuildScopeInformation(Else, NewParentScope);
408  }
409  return;
410  }
411 
412  case Stmt::CXXTryStmtClass: {
413  CXXTryStmt *TS = cast<CXXTryStmt>(S);
414  {
415  unsigned NewParentScope = Scopes.size();
416  Scopes.push_back(GotoScope(ParentScope,
417  diag::note_protected_by_cxx_try,
418  diag::note_exits_cxx_try,
419  TS->getSourceRange().getBegin()));
420  if (Stmt *TryBlock = TS->getTryBlock())
421  BuildScopeInformation(TryBlock, NewParentScope);
422  }
423 
424  // Jump from the catch into the try is not allowed either.
425  for (unsigned I = 0, E = TS->getNumHandlers(); I != E; ++I) {
426  CXXCatchStmt *CS = TS->getHandler(I);
427  unsigned NewParentScope = Scopes.size();
428  Scopes.push_back(GotoScope(ParentScope,
429  diag::note_protected_by_cxx_catch,
430  diag::note_exits_cxx_catch,
431  CS->getSourceRange().getBegin()));
432  BuildScopeInformation(CS->getHandlerBlock(), NewParentScope);
433  }
434  return;
435  }
436 
437  case Stmt::SEHTryStmtClass: {
438  SEHTryStmt *TS = cast<SEHTryStmt>(S);
439  {
440  unsigned NewParentScope = Scopes.size();
441  Scopes.push_back(GotoScope(ParentScope,
442  diag::note_protected_by_seh_try,
443  diag::note_exits_seh_try,
444  TS->getSourceRange().getBegin()));
445  if (Stmt *TryBlock = TS->getTryBlock())
446  BuildScopeInformation(TryBlock, NewParentScope);
447  }
448 
449  // Jump from __except or __finally into the __try are not allowed either.
450  if (SEHExceptStmt *Except = TS->getExceptHandler()) {
451  unsigned NewParentScope = Scopes.size();
452  Scopes.push_back(GotoScope(ParentScope,
453  diag::note_protected_by_seh_except,
454  diag::note_exits_seh_except,
455  Except->getSourceRange().getBegin()));
456  BuildScopeInformation(Except->getBlock(), NewParentScope);
457  } else if (SEHFinallyStmt *Finally = TS->getFinallyHandler()) {
458  unsigned NewParentScope = Scopes.size();
459  Scopes.push_back(GotoScope(ParentScope,
460  diag::note_protected_by_seh_finally,
461  diag::note_exits_seh_finally,
462  Finally->getSourceRange().getBegin()));
463  BuildScopeInformation(Finally->getBlock(), NewParentScope);
464  }
465 
466  return;
467  }
468 
469  case Stmt::DeclStmtClass: {
470  // If this is a declstmt with a VLA definition, it defines a scope from here
471  // to the end of the containing context.
472  DeclStmt *DS = cast<DeclStmt>(S);
473  // The decl statement creates a scope if any of the decls in it are VLAs
474  // or have the cleanup attribute.
475  for (auto *I : DS->decls())
476  BuildScopeInformation(I, origParentScope);
477  return;
478  }
479 
480  case Stmt::ObjCAtTryStmtClass: {
481  // Disallow jumps into any part of an @try statement by pushing a scope and
482  // walking all sub-stmts in that scope.
483  ObjCAtTryStmt *AT = cast<ObjCAtTryStmt>(S);
484  // Recursively walk the AST for the @try part.
485  {
486  unsigned NewParentScope = Scopes.size();
487  Scopes.push_back(GotoScope(ParentScope,
488  diag::note_protected_by_objc_try,
489  diag::note_exits_objc_try,
490  AT->getAtTryLoc()));
491  if (Stmt *TryPart = AT->getTryBody())
492  BuildScopeInformation(TryPart, NewParentScope);
493  }
494 
495  // Jump from the catch to the finally or try is not valid.
496  for (unsigned I = 0, N = AT->getNumCatchStmts(); I != N; ++I) {
497  ObjCAtCatchStmt *AC = AT->getCatchStmt(I);
498  unsigned NewParentScope = Scopes.size();
499  Scopes.push_back(GotoScope(ParentScope,
500  diag::note_protected_by_objc_catch,
501  diag::note_exits_objc_catch,
502  AC->getAtCatchLoc()));
503  // @catches are nested and it isn't
504  BuildScopeInformation(AC->getCatchBody(), NewParentScope);
505  }
506 
507  // Jump from the finally to the try or catch is not valid.
508  if (ObjCAtFinallyStmt *AF = AT->getFinallyStmt()) {
509  unsigned NewParentScope = Scopes.size();
510  Scopes.push_back(GotoScope(ParentScope,
511  diag::note_protected_by_objc_finally,
512  diag::note_exits_objc_finally,
513  AF->getAtFinallyLoc()));
514  BuildScopeInformation(AF, NewParentScope);
515  }
516 
517  return;
518  }
519 
520  case Stmt::ObjCAtSynchronizedStmtClass: {
521  // Disallow jumps into the protected statement of an @synchronized, but
522  // allow jumps into the object expression it protects.
523  ObjCAtSynchronizedStmt *AS = cast<ObjCAtSynchronizedStmt>(S);
524  // Recursively walk the AST for the @synchronized object expr, it is
525  // evaluated in the normal scope.
526  BuildScopeInformation(AS->getSynchExpr(), ParentScope);
527 
528  // Recursively walk the AST for the @synchronized part, protected by a new
529  // scope.
530  unsigned NewParentScope = Scopes.size();
531  Scopes.push_back(GotoScope(ParentScope,
532  diag::note_protected_by_objc_synchronized,
533  diag::note_exits_objc_synchronized,
534  AS->getAtSynchronizedLoc()));
535  BuildScopeInformation(AS->getSynchBody(), NewParentScope);
536  return;
537  }
538 
539  case Stmt::ObjCAutoreleasePoolStmtClass: {
540  // Disallow jumps into the protected statement of an @autoreleasepool.
541  ObjCAutoreleasePoolStmt *AS = cast<ObjCAutoreleasePoolStmt>(S);
542  // Recursively walk the AST for the @autoreleasepool part, protected by a
543  // new scope.
544  unsigned NewParentScope = Scopes.size();
545  Scopes.push_back(GotoScope(ParentScope,
546  diag::note_protected_by_objc_autoreleasepool,
547  diag::note_exits_objc_autoreleasepool,
548  AS->getAtLoc()));
549  BuildScopeInformation(AS->getSubStmt(), NewParentScope);
550  return;
551  }
552 
553  case Stmt::ExprWithCleanupsClass: {
554  // Disallow jumps past full-expressions that use blocks with
555  // non-trivial cleanups of their captures. This is theoretically
556  // implementable but a lot of work which we haven't felt up to doing.
557  ExprWithCleanups *EWC = cast<ExprWithCleanups>(S);
558  for (unsigned i = 0, e = EWC->getNumObjects(); i != e; ++i) {
559  if (auto *BDecl = EWC->getObject(i).dyn_cast<BlockDecl *>())
560  for (const auto &CI : BDecl->captures()) {
561  VarDecl *variable = CI.getVariable();
562  BuildScopeInformation(variable, BDecl, origParentScope);
563  }
564  else if (auto *CLE = EWC->getObject(i).dyn_cast<CompoundLiteralExpr *>())
565  BuildScopeInformation(CLE, origParentScope);
566  else
567  llvm_unreachable("unexpected cleanup object type");
568  }
569  break;
570  }
571 
572  case Stmt::MaterializeTemporaryExprClass: {
573  // Disallow jumps out of scopes containing temporaries lifetime-extended to
574  // automatic storage duration.
575  MaterializeTemporaryExpr *MTE = cast<MaterializeTemporaryExpr>(S);
576  if (MTE->getStorageDuration() == SD_Automatic) {
579  const Expr *ExtendedObject =
581  Adjustments);
582  if (ExtendedObject->getType().isDestructedType()) {
583  Scopes.push_back(GotoScope(ParentScope, 0,
584  diag::note_exits_temporary_dtor,
585  ExtendedObject->getExprLoc()));
586  origParentScope = Scopes.size()-1;
587  }
588  }
589  break;
590  }
591 
592  case Stmt::CaseStmtClass:
593  case Stmt::DefaultStmtClass:
594  case Stmt::LabelStmtClass:
595  LabelAndGotoScopes[S] = ParentScope;
596  break;
597 
598  case Stmt::AttributedStmtClass: {
599  AttributedStmt *AS = cast<AttributedStmt>(S);
600  if (GetMustTailAttr(AS)) {
601  LabelAndGotoScopes[AS] = ParentScope;
602  MustTailStmts.push_back(AS);
603  }
604  break;
605  }
606 
607  default:
608  if (auto *ED = dyn_cast<OMPExecutableDirective>(S)) {
609  if (!ED->isStandaloneDirective()) {
610  unsigned NewParentScope = Scopes.size();
611  Scopes.emplace_back(ParentScope,
612  diag::note_omp_protected_structured_block,
613  diag::note_omp_exits_structured_block,
614  ED->getStructuredBlock()->getBeginLoc());
615  BuildScopeInformation(ED->getStructuredBlock(), NewParentScope);
616  return;
617  }
618  }
619  break;
620  }
621 
622  for (Stmt *SubStmt : S->children()) {
623  if (!SubStmt)
624  continue;
625  if (StmtsToSkip) {
626  --StmtsToSkip;
627  continue;
628  }
629 
630  // Cases, labels, and defaults aren't "scope parents". It's also
631  // important to handle these iteratively instead of recursively in
632  // order to avoid blowing out the stack.
633  while (true) {
634  Stmt *Next;
635  if (SwitchCase *SC = dyn_cast<SwitchCase>(SubStmt))
636  Next = SC->getSubStmt();
637  else if (LabelStmt *LS = dyn_cast<LabelStmt>(SubStmt))
638  Next = LS->getSubStmt();
639  else
640  break;
641 
642  LabelAndGotoScopes[SubStmt] = ParentScope;
643  SubStmt = Next;
644  }
645 
646  // Recursively walk the AST.
647  BuildScopeInformation(SubStmt, ParentScope);
648  }
649 }
650 
651 /// VerifyJumps - Verify each element of the Jumps array to see if they are
652 /// valid, emitting diagnostics if not.
653 void JumpScopeChecker::VerifyJumps() {
654  while (!Jumps.empty()) {
655  Stmt *Jump = Jumps.pop_back_val();
656 
657  // With a goto,
658  if (GotoStmt *GS = dyn_cast<GotoStmt>(Jump)) {
659  // The label may not have a statement if it's coming from inline MS ASM.
660  if (GS->getLabel()->getStmt()) {
661  CheckJump(GS, GS->getLabel()->getStmt(), GS->getGotoLoc(),
662  diag::err_goto_into_protected_scope,
663  diag::ext_goto_into_protected_scope,
664  diag::warn_cxx98_compat_goto_into_protected_scope);
665  }
666  CheckGotoStmt(GS);
667  continue;
668  }
669 
670  // We only get indirect gotos here when they have a constant target.
671  if (IndirectGotoStmt *IGS = dyn_cast<IndirectGotoStmt>(Jump)) {
672  LabelDecl *Target = IGS->getConstantTarget();
673  CheckJump(IGS, Target->getStmt(), IGS->getGotoLoc(),
674  diag::err_goto_into_protected_scope,
675  diag::ext_goto_into_protected_scope,
676  diag::warn_cxx98_compat_goto_into_protected_scope);
677  continue;
678  }
679 
680  SwitchStmt *SS = cast<SwitchStmt>(Jump);
681  for (SwitchCase *SC = SS->getSwitchCaseList(); SC;
682  SC = SC->getNextSwitchCase()) {
683  if (CHECK_PERMISSIVE(!LabelAndGotoScopes.count(SC)))
684  continue;
685  SourceLocation Loc;
686  if (CaseStmt *CS = dyn_cast<CaseStmt>(SC))
687  Loc = CS->getBeginLoc();
688  else if (DefaultStmt *DS = dyn_cast<DefaultStmt>(SC))
689  Loc = DS->getBeginLoc();
690  else
691  Loc = SC->getBeginLoc();
692  CheckJump(SS, SC, Loc, diag::err_switch_into_protected_scope, 0,
693  diag::warn_cxx98_compat_switch_into_protected_scope);
694  }
695  }
696 }
697 
698 /// VerifyIndirectOrAsmJumps - Verify whether any possible indirect goto or
699 /// asm goto jump might cross a protection boundary. Unlike direct jumps,
700 /// indirect or asm goto jumps count cleanups as protection boundaries:
701 /// since there's no way to know where the jump is going, we can't implicitly
702 /// run the right cleanups the way we can with direct jumps.
703 /// Thus, an indirect/asm jump is "trivial" if it bypasses no
704 /// initializations and no teardowns. More formally, an indirect/asm jump
705 /// from A to B is trivial if the path out from A to DCA(A,B) is
706 /// trivial and the path in from DCA(A,B) to B is trivial, where
707 /// DCA(A,B) is the deepest common ancestor of A and B.
708 /// Jump-triviality is transitive but asymmetric.
709 ///
710 /// A path in is trivial if none of the entered scopes have an InDiag.
711 /// A path out is trivial is none of the exited scopes have an OutDiag.
712 ///
713 /// Under these definitions, this function checks that the indirect
714 /// jump between A and B is trivial for every indirect goto statement A
715 /// and every label B whose address was taken in the function.
716 void JumpScopeChecker::VerifyIndirectOrAsmJumps(bool IsAsmGoto) {
717  SmallVector<Stmt*, 4> GotoJumps = IsAsmGoto ? AsmJumps : IndirectJumps;
718  if (GotoJumps.empty())
719  return;
720  SmallVector<LabelDecl *, 4> JumpTargets =
721  IsAsmGoto ? AsmJumpTargets : IndirectJumpTargets;
722  // If there aren't any address-of-label expressions in this function,
723  // complain about the first indirect goto.
724  if (JumpTargets.empty()) {
725  assert(!IsAsmGoto &&"only indirect goto can get here");
726  S.Diag(GotoJumps[0]->getBeginLoc(),
727  diag::err_indirect_goto_without_addrlabel);
728  return;
729  }
730  // Collect a single representative of every scope containing an
731  // indirect or asm goto. For most code bases, this substantially cuts
732  // down on the number of jump sites we'll have to consider later.
733  typedef std::pair<unsigned, Stmt*> JumpScope;
734  SmallVector<JumpScope, 32> JumpScopes;
735  {
736  llvm::DenseMap<unsigned, Stmt*> JumpScopesMap;
737  for (SmallVectorImpl<Stmt *>::iterator I = GotoJumps.begin(),
738  E = GotoJumps.end();
739  I != E; ++I) {
740  Stmt *IG = *I;
741  if (CHECK_PERMISSIVE(!LabelAndGotoScopes.count(IG)))
742  continue;
743  unsigned IGScope = LabelAndGotoScopes[IG];
744  Stmt *&Entry = JumpScopesMap[IGScope];
745  if (!Entry) Entry = IG;
746  }
747  JumpScopes.reserve(JumpScopesMap.size());
748  for (llvm::DenseMap<unsigned, Stmt *>::iterator I = JumpScopesMap.begin(),
749  E = JumpScopesMap.end();
750  I != E; ++I)
751  JumpScopes.push_back(*I);
752  }
753 
754  // Collect a single representative of every scope containing a
755  // label whose address was taken somewhere in the function.
756  // For most code bases, there will be only one such scope.
757  llvm::DenseMap<unsigned, LabelDecl*> TargetScopes;
758  for (SmallVectorImpl<LabelDecl *>::iterator I = JumpTargets.begin(),
759  E = JumpTargets.end();
760  I != E; ++I) {
761  LabelDecl *TheLabel = *I;
762  if (CHECK_PERMISSIVE(!LabelAndGotoScopes.count(TheLabel->getStmt())))
763  continue;
764  unsigned LabelScope = LabelAndGotoScopes[TheLabel->getStmt()];
765  LabelDecl *&Target = TargetScopes[LabelScope];
766  if (!Target) Target = TheLabel;
767  }
768 
769  // For each target scope, make sure it's trivially reachable from
770  // every scope containing a jump site.
771  //
772  // A path between scopes always consists of exitting zero or more
773  // scopes, then entering zero or more scopes. We build a set of
774  // of scopes S from which the target scope can be trivially
775  // entered, then verify that every jump scope can be trivially
776  // exitted to reach a scope in S.
777  llvm::BitVector Reachable(Scopes.size(), false);
778  for (llvm::DenseMap<unsigned,LabelDecl*>::iterator
779  TI = TargetScopes.begin(), TE = TargetScopes.end(); TI != TE; ++TI) {
780  unsigned TargetScope = TI->first;
781  LabelDecl *TargetLabel = TI->second;
782 
783  Reachable.reset();
784 
785  // Mark all the enclosing scopes from which you can safely jump
786  // into the target scope. 'Min' will end up being the index of
787  // the shallowest such scope.
788  unsigned Min = TargetScope;
789  while (true) {
790  Reachable.set(Min);
791 
792  // Don't go beyond the outermost scope.
793  if (Min == 0) break;
794 
795  // Stop if we can't trivially enter the current scope.
796  if (Scopes[Min].InDiag) break;
797 
798  Min = Scopes[Min].ParentScope;
799  }
800 
801  // Walk through all the jump sites, checking that they can trivially
802  // reach this label scope.
804  I = JumpScopes.begin(), E = JumpScopes.end(); I != E; ++I) {
805  unsigned Scope = I->first;
806 
807  // Walk out the "scope chain" for this scope, looking for a scope
808  // we've marked reachable. For well-formed code this amortizes
809  // to O(JumpScopes.size() / Scopes.size()): we only iterate
810  // when we see something unmarked, and in well-formed code we
811  // mark everything we iterate past.
812  bool IsReachable = false;
813  while (true) {
814  if (Reachable.test(Scope)) {
815  // If we find something reachable, mark all the scopes we just
816  // walked through as reachable.
817  for (unsigned S = I->first; S != Scope; S = Scopes[S].ParentScope)
818  Reachable.set(S);
819  IsReachable = true;
820  break;
821  }
822 
823  // Don't walk out if we've reached the top-level scope or we've
824  // gotten shallower than the shallowest reachable scope.
825  if (Scope == 0 || Scope < Min) break;
826 
827  // Don't walk out through an out-diagnostic.
828  if (Scopes[Scope].OutDiag) break;
829 
830  Scope = Scopes[Scope].ParentScope;
831  }
832 
833  // Only diagnose if we didn't find something.
834  if (IsReachable) continue;
835 
836  DiagnoseIndirectOrAsmJump(I->second, I->first, TargetLabel, TargetScope);
837  }
838  }
839 }
840 
841 /// Return true if a particular error+note combination must be downgraded to a
842 /// warning in Microsoft mode.
843 static bool IsMicrosoftJumpWarning(unsigned JumpDiag, unsigned InDiagNote) {
844  return (JumpDiag == diag::err_goto_into_protected_scope &&
845  (InDiagNote == diag::note_protected_by_variable_init ||
846  InDiagNote == diag::note_protected_by_variable_nontriv_destructor));
847 }
848 
849 /// Return true if a particular note should be downgraded to a compatibility
850 /// warning in C++11 mode.
851 static bool IsCXX98CompatWarning(Sema &S, unsigned InDiagNote) {
852  return S.getLangOpts().CPlusPlus11 &&
853  InDiagNote == diag::note_protected_by_variable_non_pod;
854 }
855 
856 /// Produce primary diagnostic for an indirect jump statement.
858  LabelDecl *Target, bool &Diagnosed) {
859  if (Diagnosed)
860  return;
861  bool IsAsmGoto = isa<GCCAsmStmt>(Jump);
862  S.Diag(Jump->getBeginLoc(), diag::err_indirect_goto_in_protected_scope)
863  << IsAsmGoto;
864  S.Diag(Target->getStmt()->getIdentLoc(), diag::note_indirect_goto_target)
865  << IsAsmGoto;
866  Diagnosed = true;
867 }
868 
869 /// Produce note diagnostics for a jump into a protected scope.
870 void JumpScopeChecker::NoteJumpIntoScopes(ArrayRef<unsigned> ToScopes) {
871  if (CHECK_PERMISSIVE(ToScopes.empty()))
872  return;
873  for (unsigned I = 0, E = ToScopes.size(); I != E; ++I)
874  if (Scopes[ToScopes[I]].InDiag)
875  S.Diag(Scopes[ToScopes[I]].Loc, Scopes[ToScopes[I]].InDiag);
876 }
877 
878 /// Diagnose an indirect jump which is known to cross scopes.
879 void JumpScopeChecker::DiagnoseIndirectOrAsmJump(Stmt *Jump, unsigned JumpScope,
880  LabelDecl *Target,
881  unsigned TargetScope) {
882  if (CHECK_PERMISSIVE(JumpScope == TargetScope))
883  return;
884 
885  unsigned Common = GetDeepestCommonScope(JumpScope, TargetScope);
886  bool Diagnosed = false;
887 
888  // Walk out the scope chain until we reach the common ancestor.
889  for (unsigned I = JumpScope; I != Common; I = Scopes[I].ParentScope)
890  if (Scopes[I].OutDiag) {
891  DiagnoseIndirectOrAsmJumpStmt(S, Jump, Target, Diagnosed);
892  S.Diag(Scopes[I].Loc, Scopes[I].OutDiag);
893  }
894 
895  SmallVector<unsigned, 10> ToScopesCXX98Compat;
896 
897  // Now walk into the scopes containing the label whose address was taken.
898  for (unsigned I = TargetScope; I != Common; I = Scopes[I].ParentScope)
899  if (IsCXX98CompatWarning(S, Scopes[I].InDiag))
900  ToScopesCXX98Compat.push_back(I);
901  else if (Scopes[I].InDiag) {
902  DiagnoseIndirectOrAsmJumpStmt(S, Jump, Target, Diagnosed);
903  S.Diag(Scopes[I].Loc, Scopes[I].InDiag);
904  }
905 
906  // Diagnose this jump if it would be ill-formed in C++98.
907  if (!Diagnosed && !ToScopesCXX98Compat.empty()) {
908  bool IsAsmGoto = isa<GCCAsmStmt>(Jump);
909  S.Diag(Jump->getBeginLoc(),
910  diag::warn_cxx98_compat_indirect_goto_in_protected_scope)
911  << IsAsmGoto;
912  S.Diag(Target->getStmt()->getIdentLoc(), diag::note_indirect_goto_target)
913  << IsAsmGoto;
914  NoteJumpIntoScopes(ToScopesCXX98Compat);
915  }
916 }
917 
918 /// CheckJump - Validate that the specified jump statement is valid: that it is
919 /// jumping within or out of its current scope, not into a deeper one.
920 void JumpScopeChecker::CheckJump(Stmt *From, Stmt *To, SourceLocation DiagLoc,
921  unsigned JumpDiagError, unsigned JumpDiagWarning,
922  unsigned JumpDiagCXX98Compat) {
923  if (CHECK_PERMISSIVE(!LabelAndGotoScopes.count(From)))
924  return;
925  if (CHECK_PERMISSIVE(!LabelAndGotoScopes.count(To)))
926  return;
927 
928  unsigned FromScope = LabelAndGotoScopes[From];
929  unsigned ToScope = LabelAndGotoScopes[To];
930 
931  // Common case: exactly the same scope, which is fine.
932  if (FromScope == ToScope) return;
933 
934  // Warn on gotos out of __finally blocks.
935  if (isa<GotoStmt>(From) || isa<IndirectGotoStmt>(From)) {
936  // If FromScope > ToScope, FromScope is more nested and the jump goes to a
937  // less nested scope. Check if it crosses a __finally along the way.
938  for (unsigned I = FromScope; I > ToScope; I = Scopes[I].ParentScope) {
939  if (Scopes[I].InDiag == diag::note_protected_by_seh_finally) {
940  S.Diag(From->getBeginLoc(), diag::warn_jump_out_of_seh_finally);
941  break;
942  }
943  if (Scopes[I].InDiag == diag::note_omp_protected_structured_block) {
944  S.Diag(From->getBeginLoc(), diag::err_goto_into_protected_scope);
945  S.Diag(To->getBeginLoc(), diag::note_omp_exits_structured_block);
946  break;
947  }
948  }
949  }
950 
951  unsigned CommonScope = GetDeepestCommonScope(FromScope, ToScope);
952 
953  // It's okay to jump out from a nested scope.
954  if (CommonScope == ToScope) return;
955 
956  // Pull out (and reverse) any scopes we might need to diagnose skipping.
957  SmallVector<unsigned, 10> ToScopesCXX98Compat;
958  SmallVector<unsigned, 10> ToScopesError;
959  SmallVector<unsigned, 10> ToScopesWarning;
960  for (unsigned I = ToScope; I != CommonScope; I = Scopes[I].ParentScope) {
961  if (S.getLangOpts().MSVCCompat && JumpDiagWarning != 0 &&
962  IsMicrosoftJumpWarning(JumpDiagError, Scopes[I].InDiag))
963  ToScopesWarning.push_back(I);
964  else if (IsCXX98CompatWarning(S, Scopes[I].InDiag))
965  ToScopesCXX98Compat.push_back(I);
966  else if (Scopes[I].InDiag)
967  ToScopesError.push_back(I);
968  }
969 
970  // Handle warnings.
971  if (!ToScopesWarning.empty()) {
972  S.Diag(DiagLoc, JumpDiagWarning);
973  NoteJumpIntoScopes(ToScopesWarning);
974  assert(isa<LabelStmt>(To));
975  LabelStmt *Label = cast<LabelStmt>(To);
976  Label->setSideEntry(true);
977  }
978 
979  // Handle errors.
980  if (!ToScopesError.empty()) {
981  S.Diag(DiagLoc, JumpDiagError);
982  NoteJumpIntoScopes(ToScopesError);
983  }
984 
985  // Handle -Wc++98-compat warnings if the jump is well-formed.
986  if (ToScopesError.empty() && !ToScopesCXX98Compat.empty()) {
987  S.Diag(DiagLoc, JumpDiagCXX98Compat);
988  NoteJumpIntoScopes(ToScopesCXX98Compat);
989  }
990 }
991 
992 void JumpScopeChecker::CheckGotoStmt(GotoStmt *GS) {
993  if (GS->getLabel()->isMSAsmLabel()) {
994  S.Diag(GS->getGotoLoc(), diag::err_goto_ms_asm_label)
995  << GS->getLabel()->getIdentifier();
996  S.Diag(GS->getLabel()->getLocation(), diag::note_goto_ms_asm_label)
997  << GS->getLabel()->getIdentifier();
998  }
999 }
1000 
1001 void JumpScopeChecker::VerifyMustTailStmts() {
1002  for (AttributedStmt *AS : MustTailStmts) {
1003  for (unsigned I = LabelAndGotoScopes[AS]; I; I = Scopes[I].ParentScope) {
1004  if (Scopes[I].OutDiag) {
1005  S.Diag(AS->getBeginLoc(), diag::err_musttail_scope);
1006  S.Diag(Scopes[I].Loc, Scopes[I].OutDiag);
1007  }
1008  }
1009  }
1010 }
1011 
1012 const Attr *JumpScopeChecker::GetMustTailAttr(AttributedStmt *AS) {
1013  ArrayRef<const Attr *> Attrs = AS->getAttrs();
1014  const auto *Iter =
1015  llvm::find_if(Attrs, [](const Attr *A) { return isa<MustTailAttr>(A); });
1016  return Iter != Attrs.end() ? *Iter : nullptr;
1017 }
1018 
1019 void Sema::DiagnoseInvalidJumps(Stmt *Body) {
1020  (void)JumpScopeChecker(Body, *this);
1021 }
clang::IndirectGotoStmt
IndirectGotoStmt - This represents an indirect goto.
Definition: Stmt.h:2644
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LabelStmt - Represents a label, which has a substatement.
Definition: Stmt.h:1799
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SourceLocation getAtLoc() const
Definition: StmtObjC.h:388
clang::ObjCAtTryStmt::getNumCatchStmts
unsigned getNumCatchStmts() const
Retrieve the number of @catch statements in this try-catch-finally block.
Definition: StmtObjC.h:214
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CaseStmt - Represent a case statement.
Definition: Stmt.h:1567
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SourceLocation getBeginLoc() const
Definition: Stmt.h:1889
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Represents a C++ constructor within a class.
Definition: DeclCXX.h:2401
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SEHFinallyStmt * getFinallyHandler() const
Definition: Stmt.cpp:1248
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SourceLocation getBeginLoc() const LLVM_READONLY
Definition: StmtCXX.h:43
clang::SwitchStmt
SwitchStmt - This represents a 'switch' stmt.
Definition: Stmt.h:2150
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SourceLocation getBeginLoc() const
Definition: Stmt.h:2113
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const Stmt * getSubStmt() const
Definition: StmtObjC.h:379
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unsigned getNumHandlers() const
Definition: StmtCXX.h:106
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bool hasAttr() const
Definition: DeclBase.h:547
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bool isObjCAvailabilityCheck() const
Definition: Stmt.cpp:994
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SEHExceptStmt * getExceptHandler() const
Returns 0 if not defined.
Definition: Stmt.cpp:1244
Diag
static DiagnosticBuilder Diag(DiagnosticsEngine *Diags, const LangOptions &Features, FullSourceLoc TokLoc, const char *TokBegin, const char *TokRangeBegin, const char *TokRangeEnd, unsigned DiagID)
Produce a diagnostic highlighting some portion of a literal.
Definition: LiteralSupport.cpp:78
SemaInternal.h
llvm::SmallVector
Definition: LLVM.h:38
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Encodes a location in the source.
Definition: SourceLocation.h:88
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Expr * getSubExpr() const
Retrieve the temporary-generating subexpression whose value will be materialized into a glvalue.
Definition: ExprCXX.h:4479
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SourceLocation getBegin() const
Definition: SourceLocation.h:221
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unsigned getNumObjects() const
Definition: ExprCXX.h:3375
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@ Target
clang::ObjCAtSynchronizedStmt::getSynchBody
const CompoundStmt * getSynchBody() const
Definition: StmtObjC.h:297
clang::Stmt::getSourceRange
SourceRange getSourceRange() const LLVM_READONLY
SourceLocation tokens are not useful in isolation - they are low level value objects created/interpre...
Definition: Stmt.cpp:324
clang::QualType
A (possibly-)qualified type.
Definition: Type.h:673
clang::Sema::Diag
SemaDiagnosticBuilder Diag(SourceLocation Loc, unsigned DiagID, bool DeferHint=false)
Emit a diagnostic.
Definition: Sema.cpp:1834
DeclCXX.h
clang::IfStmt
IfStmt - This represents an if/then/else.
Definition: Stmt.h:1904
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Represents Objective-C's @try ... @catch ... @finally statement.
Definition: StmtObjC.h:165
clang::GotoStmt
GotoStmt - This represents a direct goto.
Definition: Stmt.h:2605
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StorageDuration getStorageDuration() const
Retrieve the storage duration for the materialized temporary.
Definition: ExprCXX.h:4487
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CXXCatchStmt * getHandler(unsigned i)
Definition: StmtCXX.h:107
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@ SD_Automatic
Automatic storage duration (most local variables).
Definition: Specifiers.h:308
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ASTContext & Context
Definition: Sema.h:411
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Definition: Stmt.h:3408
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Stmt * getHandlerBlock() const
Definition: StmtCXX.h:51
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const LangOptions & getLangOpts() const
Definition: Sema.h:1569
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ArrayRef< Capture > captures() const
Definition: Decl.h:4284
U
clang::AttributedStmt
Represents an attribute applied to a statement.
Definition: Stmt.h:1846
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const Expr * skipRValueSubobjectAdjustments(SmallVectorImpl< const Expr * > &CommaLHS, SmallVectorImpl< SubobjectAdjustment > &Adjustments) const
Walk outwards from an expression we want to bind a reference to and find the expression whose lifetim...
Definition: Expr.cpp:80
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SourceLocation getBeginLoc() const LLVM_READONLY
Definition: Stmt.h:1318
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Represents Objective-C's @catch statement.
Definition: StmtObjC.h:77
StmtOpenMP.h
clang::FunctionDecl::isTrivial
bool isTrivial() const
Whether this function is "trivial" in some specialized C++ senses.
Definition: Decl.h:2207
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Represents a block literal declaration, which is like an unnamed FunctionDecl.
Definition: Decl.h:4157
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Scope - A scope is a transient data structure that is used while parsing the program.
Definition: Scope.h:40
clang::MaterializeTemporaryExpr
Represents a prvalue temporary that is written into memory so that a reference can bind to it.
Definition: ExprCXX.h:4462
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LabelDecl * getLabel() const
Definition: Stmt.h:2618
clang::LabelDecl
Represents the declaration of a label.
Definition: Decl.h:496
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Represents Objective-C's @synchronized statement.
Definition: StmtObjC.h:277
clang::CXXRecordDecl::isPOD
bool isPOD() const
Whether this class is a POD-type (C++ [class]p4)
Definition: DeclCXX.h:1126
Expr.h
clang::VarDecl
Represents a variable declaration or definition.
Definition: Decl.h:876
clang::ExprWithCleanups
Represents an expression – generally a full-expression – that introduces cleanups to be run at the en...
Definition: ExprCXX.h:3342
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Represents Objective-C's @finally statement.
Definition: StmtObjC.h:127
GetDiagForGotoScopeDecl
static ScopePair GetDiagForGotoScopeDecl(Sema &S, const Decl *D)
GetDiagForGotoScopeDecl - If this decl induces a new goto scope, return a diagnostic that should be e...
Definition: JumpDiagnostics.cpp:144
clang::CXXTryStmt::getTryBlock
CompoundStmt * getTryBlock()
Definition: StmtCXX.h:99
clang::IfStmt::getElse
Stmt * getElse()
Definition: Stmt.h:2004
clang::CXXTryStmt
CXXTryStmt - A C++ try block, including all handlers.
Definition: StmtCXX.h:68
clang::SwitchCase
Definition: Stmt.h:1522
ExprCXX.h
Label
std::string Label
Definition: UsingDeclarationsSorter.cpp:69
clang::ObjCAtCatchStmt::getCatchBody
const Stmt * getCatchBody() const
Definition: StmtObjC.h:93
StmtObjC.h
clang::SEHExceptStmt
Definition: Stmt.h:3329
clang::CXXConstructorDecl::isDefaultConstructor
bool isDefaultConstructor() const
Whether this constructor is a default constructor (C++ [class.ctor]p5), which can be used to default-...
Definition: DeclCXX.cpp:2633
clang::CompoundLiteralExpr
CompoundLiteralExpr - [C99 6.5.2.5].
Definition: Expr.h:3403
SourceLocation.h
clang::LabelDecl::getStmt
LabelStmt * getStmt() const
Definition: Decl.h:520
IsCXX98CompatWarning
static bool IsCXX98CompatWarning(Sema &S, unsigned InDiagNote)
Return true if a particular note should be downgraded to a compatibility warning in C++11 mode.
Definition: JumpDiagnostics.cpp:851
clang::AttributedStmt::getAttrs
ArrayRef< const Attr * > getAttrs() const
Definition: Stmt.h:1882
clang::NamedDecl::getIdentifier
IdentifierInfo * getIdentifier() const
Get the identifier that names this declaration, if there is one.
Definition: Decl.h:270
clang::ObjCAtSynchronizedStmt::getAtSynchronizedLoc
SourceLocation getAtSynchronizedLoc() const
Definition: StmtObjC.h:294
clang::IfStmt::isConsteval
bool isConsteval() const
Definition: Stmt.h:2081
clang::Expr::getExprLoc
SourceLocation getExprLoc() const LLVM_READONLY
getExprLoc - Return the preferred location for the arrow when diagnosing a problem with a generic exp...
Definition: Expr.cpp:229
llvm::ArrayRef< unsigned >
clang::ObjCAtTryStmt::getAtTryLoc
SourceLocation getAtTryLoc() const
Retrieve the location of the @ in the @try.
Definition: StmtObjC.h:204
clang::Decl
Decl - This represents one declaration (or definition), e.g.
Definition: DeclBase.h:89
CHECK_PERMISSIVE
#define CHECK_PERMISSIVE(x)
Definition: JumpDiagnostics.cpp:104
DiagnoseIndirectOrAsmJumpStmt
static void DiagnoseIndirectOrAsmJumpStmt(Sema &S, Stmt *Jump, LabelDecl *Target, bool &Diagnosed)
Produce primary diagnostic for an indirect jump statement.
Definition: JumpDiagnostics.cpp:857
clang::Sema
Sema - This implements semantic analysis and AST building for C.
Definition: Sema.h:355
clang::QualType::DestructionKind
DestructionKind
Definition: Type.h:1202
clang::IfStmt::getConditionVariable
VarDecl * getConditionVariable()
Retrieve the variable declared in this "if" statement, if any.
Definition: Stmt.cpp:973
clang::DeclStmt
DeclStmt - Adaptor class for mixing declarations with statements and expressions.
Definition: Stmt.h:1292
clang::ObjCAtTryStmt::getTryBody
const Stmt * getTryBody() const
Retrieve the @try body.
Definition: StmtObjC.h:208
clang::IfStmt::getCond
Expr * getCond()
Definition: Stmt.h:1983
clang::ExprWithCleanups::getObject
CleanupObject getObject(unsigned i) const
Definition: ExprCXX.h:3377
clang::SEHFinallyStmt
Definition: Stmt.h:3373
clang::IfStmt::isConstexpr
bool isConstexpr() const
Definition: Stmt.h:2094
clang::ObjCAtCatchStmt::getAtCatchLoc
SourceLocation getAtCatchLoc() const
Definition: StmtObjC.h:105
clang::SourceLocation::isInvalid
bool isInvalid() const
Definition: SourceLocation.h:113
clang
Definition: CalledOnceCheck.h:17
clang::Stmt
Stmt - This represents one statement.
Definition: Stmt.h:69
clang::DefaultStmt
Definition: Stmt.h:1723
clang::ObjCAutoreleasePoolStmt
Represents Objective-C's @autoreleasepool Statement.
Definition: StmtObjC.h:368
clang::CXXCatchStmt
CXXCatchStmt - This represents a C++ catch block.
Definition: StmtCXX.h:28
clang::GotoStmt::getGotoLoc
SourceLocation getGotoLoc() const
Definition: Stmt.h:2621
clang::Expr::getType
QualType getType() const
Definition: Expr.h:141
clang::Attr
Attr - This represents one attribute.
Definition: Attr.h:46
s
__device__ __2f16 float bool s
Definition: __clang_hip_libdevice_declares.h:315
clang::DeclStmt::decls
decl_range decls()
Definition: Stmt.h:1340
clang::Stmt::getBeginLoc
SourceLocation getBeginLoc() const LLVM_READONLY
Definition: Stmt.cpp:336
clang::SEHTryStmt::getTryBlock
CompoundStmt * getTryBlock() const
Definition: Stmt.h:3437
clang::IfStmt::getThen
Stmt * getThen()
Definition: Stmt.h:1995
clang::TypedefNameDecl
Base class for declarations which introduce a typedef-name.
Definition: Decl.h:3180
clang::ObjCAtTryStmt::getCatchStmt
const ObjCAtCatchStmt * getCatchStmt(unsigned I) const
Retrieve a @catch statement.
Definition: StmtObjC.h:217
ScopePair
std::pair< unsigned, unsigned > ScopePair
Definition: JumpDiagnostics.cpp:140
llvm::SmallVectorImpl
Definition: LLVM.h:39
clang::ValueDecl::getType
QualType getType() const
Definition: Decl.h:687
clang::Expr
This represents one expression.
Definition: Expr.h:109
clang::LabelDecl::isMSAsmLabel
bool isMSAsmLabel() const
Definition: Decl.h:530
clang::QualType::isDestructedType
DestructionKind isDestructedType() const
Returns a nonzero value if objects of this type require non-trivial work to clean up after.
Definition: Type.h:1214
clang::SwitchStmt::getSwitchCaseList
SwitchCase * getSwitchCaseList()
Definition: Stmt.h:2283
clang::ObjCAtSynchronizedStmt::getSynchExpr
const Expr * getSynchExpr() const
Definition: StmtObjC.h:305
clang::Decl::getLocation
SourceLocation getLocation() const
Definition: DeclBase.h:430
clang::ObjCAtTryStmt::getFinallyStmt
const ObjCAtFinallyStmt * getFinallyStmt() const
Retrieve the @finally statement, if any.
Definition: StmtObjC.h:235
StmtCXX.h
clang::CXXConstructExpr
Represents a call to a C++ constructor.
Definition: ExprCXX.h:1460
IsMicrosoftJumpWarning
static bool IsMicrosoftJumpWarning(unsigned JumpDiag, unsigned InDiagNote)
Return true if a particular error+note combination must be downgraded to a warning in Microsoft mode.
Definition: JumpDiagnostics.cpp:843
clang::ASTContext::getLangOpts
const LangOptions & getLangOpts() const
Definition: ASTContext.h:765
clang::CXXMethodDecl::getParent
const CXXRecordDecl * getParent() const
Return the parent of this method declaration, which is the class in which this method is defined.
Definition: DeclCXX.h:2063
clang::SwitchCase::getNextSwitchCase
const SwitchCase * getNextSwitchCase() const
Definition: Stmt.h:1542