Refactor DelayedDiagnostics so that it keeps diagnostics in

separate pools owned by the RAII objects that keep pushing
decl state.  This gives us quite a bit more flexibility.

llvm-svn: 156289

clang/include/clang/Parse/Parser.h

@@ -31,6 +31,9 @@ namespace clang {
   class DeclGroupRef;
   class DiagnosticBuilder;
   class Parser;
+  class ParsingDeclRAIIObject;
+  class ParsingDeclSpec;
+  class ParsingDeclarator;
   class PragmaUnusedHandler;
   class ColonProtectionRAIIObject;
   class InMessageExpressionRAIIObject;
@@ -207,6 +210,7 @@ public:
   const TargetInfo &getTargetInfo() const { return PP.getTargetInfo(); }
   Preprocessor &getPreprocessor() const { return PP; }
   Sema &getActions() const { return Actions; }
+  AttributeFactory &getAttrFactory() { return AttrFactory; }
 
   const Token &getCurToken() const { return Tok; }
   Scope *getCurScope() const { return Actions.getCurScope(); }
@@ -951,120 +955,7 @@ private:
     return *ClassStack.top();
   }
 
-  /// \brief RAII object used to inform the actions that we're
+  /// \brief RAII object used to manage the parsing of a class definition.
-  /// currently parsing a declaration.  This is active when parsing a
-  /// variable's initializer, but not when parsing the body of a
-  /// class or function definition.
-  class ParsingDeclRAIIObject {
-    Sema &Actions;
-    Sema::ParsingDeclState State;
-    bool Popped;
-
-  public:
-    ParsingDeclRAIIObject(Parser &P) : Actions(P.Actions) {
-      push();
-    }
-
-    ParsingDeclRAIIObject(Parser &P, ParsingDeclRAIIObject *Other)
-        : Actions(P.Actions) {
-      if (Other) steal(*Other);
-      else push();
-    }
-
-    /// Creates a RAII object which steals the state from a different
-    /// object instead of pushing.
-    ParsingDeclRAIIObject(ParsingDeclRAIIObject &Other)
-        : Actions(Other.Actions) {
-      steal(Other);
-    }
-
-    ~ParsingDeclRAIIObject() {
-      abort();
-    }
-
-    /// Resets the RAII object for a new declaration.
-    void reset() {
-      abort();
-      push();
-    }
-
-    /// Signals that the context was completed without an appropriate
-    /// declaration being parsed.
-    void abort() {
-      pop(0);
-    }
-
-    void complete(Decl *D) {
-      assert(!Popped && "ParsingDeclaration has already been popped!");
-      pop(D);
-    }
-
-  private:
-    void steal(ParsingDeclRAIIObject &Other) {
-      State = Other.State;
-      Popped = Other.Popped;
-      Other.Popped = true;
-    }
-
-    void push() {
-      State = Actions.PushParsingDeclaration();
-      Popped = false;
-    }
-
-    void pop(Decl *D) {
-      if (!Popped) {
-        Actions.PopParsingDeclaration(State, D);
-        Popped = true;
-      }
-    }
-  };
-
-  /// A class for parsing a DeclSpec.
-  class ParsingDeclSpec : public DeclSpec {
-    ParsingDeclRAIIObject ParsingRAII;
-
-  public:
-    ParsingDeclSpec(Parser &P) : DeclSpec(P.AttrFactory), ParsingRAII(P) {}
-    ParsingDeclSpec(Parser &P, ParsingDeclRAIIObject *RAII)
-      : DeclSpec(P.AttrFactory), ParsingRAII(P, RAII) {}
-
-    void complete(Decl *D) {
-      ParsingRAII.complete(D);
-    }
-
-    void abort() {
-      ParsingRAII.abort();
-    }
-  };
-
-  /// A class for parsing a declarator.
-  class ParsingDeclarator : public Declarator {
-    ParsingDeclRAIIObject ParsingRAII;
-
-  public:
-    ParsingDeclarator(Parser &P, const ParsingDeclSpec &DS, TheContext C)
-      : Declarator(DS, C), ParsingRAII(P) {
-    }
-
-    const ParsingDeclSpec &getDeclSpec() const {
-      return static_cast<const ParsingDeclSpec&>(Declarator::getDeclSpec());
-    }
-
-    ParsingDeclSpec &getMutableDeclSpec() const {
-      return const_cast<ParsingDeclSpec&>(getDeclSpec());
-    }
-
-    void clear() {
-      Declarator::clear();
-      ParsingRAII.reset();
-    }
-
-    void complete(Decl *D) {
-      ParsingRAII.complete(D);
-    }
-  };
-
-  /// \brief RAII object used to
   class ParsingClassDefinition {
     Parser &P;
     bool Popped;

clang/include/clang/Sema/DelayedDiagnostic.h

@@ -21,7 +21,7 @@
 #ifndef LLVM_CLANG_SEMA_DELAYED_DIAGNOSTIC_H
 #define LLVM_CLANG_SEMA_DELAYED_DIAGNOSTIC_H
 
-#include "clang/AST/DeclCXX.h"
+#include "clang/Sema/Sema.h"
 
 namespace clang {
 namespace sema {
@@ -214,7 +214,63 @@ private:
   };
 };
 
+/// DelayedDiagnosticPool - A collection of diagnostics which were
+/// delayed.
+class DelayedDiagnosticPool {
+  const DelayedDiagnosticPool *Parent;
+  llvm::SmallVector<DelayedDiagnostic, 4> Diagnostics;
+
+  // Do not implement.
+  DelayedDiagnosticPool(const DelayedDiagnosticPool &other);
+  DelayedDiagnosticPool &operator=(const DelayedDiagnosticPool &other);
+public:
+  DelayedDiagnosticPool(const DelayedDiagnosticPool *parent) : Parent(parent) {}
+  ~DelayedDiagnosticPool() {
+    for (llvm::SmallVectorImpl<DelayedDiagnostic>::iterator
+           i = Diagnostics.begin(), e = Diagnostics.end(); i != e; ++i)
+      i->Destroy();
+  }
+
+  const DelayedDiagnosticPool *getParent() const { return Parent; }
+
+  /// Does this pool, or any of its ancestors, contain any diagnostics?
+  bool empty() const {
+    return (Diagnostics.empty() && (Parent == NULL || Parent->empty()));
+  }
+
+  /// Add a diagnostic to this pool.
+  void add(const DelayedDiagnostic &diag) {
+    Diagnostics.push_back(diag);
+  }
+
+  /// Steal the diagnostics from the given pool.
+  void steal(DelayedDiagnosticPool &pool) {
+    if (pool.Diagnostics.empty()) return;
+
+    if (Diagnostics.empty()) {
+      Diagnostics = llvm_move(pool.Diagnostics);
+    } else {
+      Diagnostics.append(pool.pool_begin(), pool.pool_end());
+    }
+    pool.Diagnostics.clear();
+  }
+
+  typedef llvm::SmallVectorImpl<DelayedDiagnostic>::const_iterator
+    pool_iterator;
+  pool_iterator pool_begin() const { return Diagnostics.begin(); }
+  pool_iterator pool_end() const { return Diagnostics.end(); }
+  bool pool_empty() const { return Diagnostics.empty(); }
+};
+
 }
+
+/// Add a diagnostic to the current delay pool.
+inline void Sema::DelayedDiagnostics::add(const sema::DelayedDiagnostic &diag) {
+  assert(shouldDelayDiagnostics() && "trying to delay without pool");
+  CurPool->add(diag);
+}
+
+
 }
 
 #endif

clang/include/clang/Sema/Sema.h

@@ -169,6 +169,7 @@ namespace sema {
   class BlockScopeInfo;
   class CompoundScopeInfo;
   class DelayedDiagnostic;
+  class DelayedDiagnosticPool;
   class FunctionScopeInfo;
   class LambdaScopeInfo;
   class PossiblyUnreachableDiag;
@@ -355,93 +356,63 @@ public:
 
   class DelayedDiagnostics;
 
-  class ParsingDeclState {
+  class DelayedDiagnosticsState {
-    unsigned SavedStackSize;
+    sema::DelayedDiagnosticPool *SavedPool;
-    friend class Sema::DelayedDiagnostics;
-  };
-
-  class ProcessingContextState {
-    unsigned SavedParsingDepth;
-    unsigned SavedActiveStackBase;
     friend class Sema::DelayedDiagnostics;
   };
+  typedef DelayedDiagnosticsState ParsingDeclState;
+  typedef DelayedDiagnosticsState ProcessingContextState;
 
   /// A class which encapsulates the logic for delaying diagnostics
   /// during parsing and other processing.
   class DelayedDiagnostics {
-    /// \brief The stack of diagnostics that were delayed due to being
+    /// \brief The current pool of diagnostics into which delayed
-    /// produced during the parsing of a declaration.
+    /// diagnostics should go.
-    sema::DelayedDiagnostic *Stack;
+    sema::DelayedDiagnosticPool *CurPool;
-
-    /// \brief The number of objects on the delayed-diagnostics stack.
-    unsigned StackSize;
-
-    /// \brief The current capacity of the delayed-diagnostics stack.
-    unsigned StackCapacity;
-
-    /// \brief The index of the first "active" delayed diagnostic in
-    /// the stack.  When parsing class definitions, we ignore active
-    /// delayed diagnostics from the surrounding context.
-    unsigned ActiveStackBase;
-
-    /// \brief The depth of the declarations we're currently parsing.
-    /// This gets saved and reset whenever we enter a class definition.
-    unsigned ParsingDepth;
 
   public:
-    DelayedDiagnostics() : Stack(0), StackSize(0), StackCapacity(0),
+    DelayedDiagnostics() : CurPool(0) {}
-      ActiveStackBase(0), ParsingDepth(0) {}
 
-    ~DelayedDiagnostics() {
+    /// Adds a delayed diagnostic.    
-      delete[] reinterpret_cast<char*>(Stack);
+    void add(const sema::DelayedDiagnostic &diag); // in DelayedDiagnostic.h
-    }
-
-    /// Adds a delayed diagnostic.
-    void add(const sema::DelayedDiagnostic &diag);
 
     /// Determines whether diagnostics should be delayed.
-    bool shouldDelayDiagnostics() { return ParsingDepth > 0; }
+    bool shouldDelayDiagnostics() { return CurPool != 0; }
 
-    /// Observe that we've started parsing a declaration.  Access and
+    /// Returns the current delayed-diagnostics pool.
-    /// deprecation diagnostics will be delayed; when the declaration
+    sema::DelayedDiagnosticPool *getCurrentPool() const {
-    /// is completed, all active delayed diagnostics will be evaluated
+      return CurPool;
-    /// in its context, and then active diagnostics stack will be
+    }
-    /// popped down to the saved depth.
-    ParsingDeclState pushParsingDecl() {
-      ParsingDepth++;
 
-      ParsingDeclState state;
+    /// Enter a new scope.  Access and deprecation diagnostics will be
-      state.SavedStackSize = StackSize;
+    /// collected in this pool.
+    DelayedDiagnosticsState push(sema::DelayedDiagnosticPool &pool) {
+      DelayedDiagnosticsState state;
+      state.SavedPool = CurPool;
+      CurPool = &pool;
       return state;
     }
 
-    /// Observe that we're completed parsing a declaration.
+    /// Leave a delayed-diagnostic state that was previously pushed.
-    static void popParsingDecl(Sema &S, ParsingDeclState state, Decl *decl);
+    /// Do not emit any of the diagnostics.  This is performed as part
-
+    /// of the bookkeeping of popping a pool "properly".
-    /// Observe that we've started processing a different context, the
+    void popWithoutEmitting(DelayedDiagnosticsState state) {
-    /// contents of which are semantically separate from the
+      CurPool = state.SavedPool;
-    /// declarations it may lexically appear in.  This sets aside the
+    }
-    /// current stack of active diagnostics and starts afresh.
-    ProcessingContextState pushContext() {
-      assert(StackSize >= ActiveStackBase);
-
-      ProcessingContextState state;
-      state.SavedParsingDepth = ParsingDepth;
-      state.SavedActiveStackBase = ActiveStackBase;
-
-      ActiveStackBase = StackSize;
-      ParsingDepth = 0;
 
+    /// Enter a new scope where access and deprecation diagnostics are
+    /// not delayed.
+    DelayedDiagnosticsState pushUndelayed() {
+      DelayedDiagnosticsState state;
+      state.SavedPool = CurPool;
+      CurPool = 0;
       return state;
     }
 
-    /// Observe that we've stopped processing a context.  This
+    /// Undo a previous pushUndelayed().
-    /// restores the previous stack of active diagnostics.
+    void popUndelayed(DelayedDiagnosticsState state) {
-    void popContext(ProcessingContextState state) {
+      assert(CurPool == NULL);
-      assert(ActiveStackBase == StackSize);
+      CurPool = state.SavedPool;
-      assert(ParsingDepth == 0);
-      ActiveStackBase = state.SavedActiveStackBase;
-      ParsingDepth = state.SavedParsingDepth;
     }
   } DelayedDiagnostics;
 
@@ -456,7 +427,7 @@ public:
   public:
     ContextRAII(Sema &S, DeclContext *ContextToPush)
       : S(S), SavedContext(S.CurContext),
-        SavedContextState(S.DelayedDiagnostics.pushContext()),
+        SavedContextState(S.DelayedDiagnostics.pushUndelayed()),
         SavedCXXThisTypeOverride(S.CXXThisTypeOverride)
     {
       assert(ContextToPush && "pushing null context");
@@ -466,7 +437,7 @@ public:
     void pop() {
       if (!SavedContext) return;
       S.CurContext = SavedContext;
-      S.DelayedDiagnostics.popContext(SavedContextState);
+      S.DelayedDiagnostics.popUndelayed(SavedContextState);
       S.CXXThisTypeOverride = SavedCXXThisTypeOverride;
       SavedContext = 0;
     }
@@ -2608,19 +2579,17 @@ public:
   void DiagnoseEmptyLoopBody(const Stmt *S,
                              const Stmt *PossibleBody);
 
-  ParsingDeclState PushParsingDeclaration() {
+  ParsingDeclState PushParsingDeclaration(sema::DelayedDiagnosticPool &pool) {
-    return DelayedDiagnostics.pushParsingDecl();
+    return DelayedDiagnostics.push(pool);
-  }
-  void PopParsingDeclaration(ParsingDeclState state, Decl *decl) {
-    DelayedDiagnostics::popParsingDecl(*this, state, decl);
   }
+  void PopParsingDeclaration(ParsingDeclState state, Decl *decl);
 
   typedef ProcessingContextState ParsingClassState;
   ParsingClassState PushParsingClass() {
-    return DelayedDiagnostics.pushContext();
+    return DelayedDiagnostics.pushUndelayed();
   }
   void PopParsingClass(ParsingClassState state) {
-    DelayedDiagnostics.popContext(state);
+    DelayedDiagnostics.popUndelayed(state);
   }
 
   void EmitDeprecationWarning(NamedDecl *D, StringRef Message,

clang/lib/Parse/ParseCXXInlineMethods.cpp

@@ -16,6 +16,7 @@
 #include "clang/Sema/DeclSpec.h"
 #include "clang/Sema/Scope.h"
 #include "clang/AST/DeclTemplate.h"
+#include "RAIIObjectsForParser.h"
 using namespace clang;
 
 /// ParseCXXInlineMethodDef - We parsed and verified that the specified

clang/lib/Parse/ParseDecl.cpp

@@ -2560,7 +2560,7 @@ ParseStructDeclaration(DeclSpec &DS, FieldCallback &Fields) {
   bool FirstDeclarator = true;
   SourceLocation CommaLoc;
   while (1) {
-    ParsingDeclRAIIObject PD(*this);
+    ParsingDeclRAIIObject PD(*this, ParsingDeclRAIIObject::NoParent);
     FieldDeclarator DeclaratorInfo(DS);
     DeclaratorInfo.D.setCommaLoc(CommaLoc);
 
@@ -3067,7 +3067,7 @@ void Parser::ParseEnumBody(SourceLocation StartLoc, Decl *EnumDecl) {
 
     SourceLocation EqualLoc;
     ExprResult AssignedVal;
-    ParsingDeclRAIIObject PD(*this);
+    ParsingDeclRAIIObject PD(*this, ParsingDeclRAIIObject::NoParent);
     
     if (Tok.is(tok::equal)) {
       EqualLoc = ConsumeToken();

clang/lib/Parse/ParseObjc.cpp

@@ -965,7 +965,7 @@ Decl *Parser::ParseObjCMethodDecl(SourceLocation mLoc,
                                   tok::TokenKind mType,
                                   tok::ObjCKeywordKind MethodImplKind,
                                   bool MethodDefinition) {
-  ParsingDeclRAIIObject PD(*this);
+  ParsingDeclRAIIObject PD(*this, ParsingDeclRAIIObject::NoParent);
 
   if (Tok.is(tok::code_completion)) {
     Actions.CodeCompleteObjCMethodDecl(getCurScope(), mType == tok::minus, 

clang/lib/Parse/ParseTemplate.cpp

@@ -90,7 +90,8 @@ Parser::ParseTemplateDeclarationOrSpecialization(unsigned Context,
 
   // Tell the action that names should be checked in the context of
   // the declaration to come.
-  ParsingDeclRAIIObject ParsingTemplateParams(*this);
+  ParsingDeclRAIIObject
+    ParsingTemplateParams(*this, ParsingDeclRAIIObject::NoParent);
 
   // Parse multiple levels of template headers within this template
   // parameter scope, e.g.,
@@ -213,10 +214,11 @@ Parser::ParseSingleDeclarationAfterTemplate(
     return ParseUsingDirectiveOrDeclaration(Context, TemplateInfo, DeclEnd,
                                             prefixAttrs);
 
-  // Parse the declaration specifiers, stealing the accumulated
+  // Parse the declaration specifiers, stealing any diagnostics from
-  // diagnostics from the template parameters.
+  // the template parameters.
   ParsingDeclSpec DS(*this, &DiagsFromTParams);
 
+  // Move the attributes from the prefix into the DS.
   DS.takeAttributesFrom(prefixAttrs);
 
   ParseDeclarationSpecifiers(DS, TemplateInfo, AS,
@@ -1132,7 +1134,8 @@ Decl *Parser::ParseExplicitInstantiation(unsigned Context,
                                          SourceLocation &DeclEnd,
                                          AccessSpecifier AS) {
   // This isn't really required here.
-  ParsingDeclRAIIObject ParsingTemplateParams(*this);
+  ParsingDeclRAIIObject
+    ParsingTemplateParams(*this, ParsingDeclRAIIObject::NoParent);
 
   return ParseSingleDeclarationAfterTemplate(Context,
                                              ParsedTemplateInfo(ExternLoc,

clang/lib/Parse/RAIIObjectsForParser.h

@@ -16,13 +16,156 @@
 #define LLVM_CLANG_PARSE_RAII_OBJECTS_FOR_PARSER_H
 
 #include "clang/Parse/ParseDiagnostic.h"
+#include "clang/Parse/Parser.h"
+#include "clang/Sema/DelayedDiagnostic.h"
+#include "clang/Sema/Sema.h"
 
 namespace clang {
-  // TODO: move ParsingDeclRAIIObject here.
   // TODO: move ParsingClassDefinition here.
   // TODO: move TentativeParsingAction here.
-  
+
-  
+  /// \brief RAII object used to inform the actions that we're
+  /// currently parsing a declaration.  This is active when parsing a
+  /// variable's initializer, but not when parsing the body of a
+  /// class or function definition.
+  class ParsingDeclRAIIObject {
+    Sema &Actions;
+    sema::DelayedDiagnosticPool DiagnosticPool;
+    Sema::ParsingDeclState State;
+    bool Popped;
+
+    // Do not implement.
+    ParsingDeclRAIIObject(const ParsingDeclRAIIObject &other);
+    ParsingDeclRAIIObject &operator=(const ParsingDeclRAIIObject &other);
+
+  public:
+    enum NoParent_t { NoParent };
+    ParsingDeclRAIIObject(Parser &P, NoParent_t _)
+        : Actions(P.getActions()), DiagnosticPool(NULL) {
+      push();
+    }
+
+    /// Creates a RAII object whose pool is optionally parented by another.
+    ParsingDeclRAIIObject(Parser &P,
+                          const sema::DelayedDiagnosticPool *parentPool)
+        : Actions(P.getActions()), DiagnosticPool(parentPool) {
+      push();
+    }
+
+    /// Creates a RAII object and, optionally, initialize its
+    /// diagnostics pool by stealing the diagnostics from another
+    /// RAII object (which is assumed to be the current top pool).
+    ParsingDeclRAIIObject(Parser &P, ParsingDeclRAIIObject *other)
+        : Actions(P.getActions()),
+          DiagnosticPool(other ? other->DiagnosticPool.getParent() : NULL) {
+      if (other) {
+        DiagnosticPool.steal(other->DiagnosticPool);
+        other->abort();
+      }
+      push();
+    }
+
+    ~ParsingDeclRAIIObject() {
+      abort();
+    }
+
+    sema::DelayedDiagnosticPool &getDelayedDiagnosticPool() {
+      return DiagnosticPool;
+    }
+    const sema::DelayedDiagnosticPool &getDelayedDiagnosticPool() const {
+      return DiagnosticPool;
+    }
+
+    /// Resets the RAII object for a new declaration.
+    void reset() {
+      abort();
+      push();
+    }
+
+    /// Signals that the context was completed without an appropriate
+    /// declaration being parsed.
+    void abort() {
+      pop(0);
+    }
+
+    void complete(Decl *D) {
+      assert(!Popped && "ParsingDeclaration has already been popped!");
+      pop(D);
+    }
+
+  private:
+    void steal(ParsingDeclRAIIObject &Other) {
+      DiagnosticPool.steal(Other.DiagnosticPool);
+      State = Other.State;
+      Popped = Other.Popped;
+      Other.Popped = true;
+    }
+
+    void push() {
+      State = Actions.PushParsingDeclaration(DiagnosticPool);
+      Popped = false;
+    }
+
+    void pop(Decl *D) {
+      if (!Popped) {
+        Actions.PopParsingDeclaration(State, D);
+        Popped = true;
+      }
+    }
+  };
+
+  /// A class for parsing a DeclSpec.
+  class ParsingDeclSpec : public DeclSpec {
+    ParsingDeclRAIIObject ParsingRAII;
+
+  public:
+    ParsingDeclSpec(Parser &P)
+      : DeclSpec(P.getAttrFactory()),
+        ParsingRAII(P, ParsingDeclRAIIObject::NoParent) {}
+    ParsingDeclSpec(Parser &P, ParsingDeclRAIIObject *RAII)
+      : DeclSpec(P.getAttrFactory()),
+        ParsingRAII(P, RAII) {}
+
+    const sema::DelayedDiagnosticPool &getDelayedDiagnosticPool() const {
+      return ParsingRAII.getDelayedDiagnosticPool();
+    }
+
+    void complete(Decl *D) {
+      ParsingRAII.complete(D);
+    }
+
+    void abort() {
+      ParsingRAII.abort();
+    }
+  };
+
+  /// A class for parsing a declarator.
+  class ParsingDeclarator : public Declarator {
+    ParsingDeclRAIIObject ParsingRAII;
+
+  public:
+    ParsingDeclarator(Parser &P, const ParsingDeclSpec &DS, TheContext C)
+      : Declarator(DS, C), ParsingRAII(P, &DS.getDelayedDiagnosticPool()) {
+    }
+
+    const ParsingDeclSpec &getDeclSpec() const {
+      return static_cast<const ParsingDeclSpec&>(Declarator::getDeclSpec());
+    }
+
+    ParsingDeclSpec &getMutableDeclSpec() const {
+      return const_cast<ParsingDeclSpec&>(getDeclSpec());
+    }
+
+    void clear() {
+      Declarator::clear();
+      ParsingRAII.reset();
+    }
+
+    void complete(Decl *D) {
+      ParsingRAII.complete(D);
+    }
+  };
+
   /// ExtensionRAIIObject - This saves the state of extension warnings when
   /// constructed and disables them.  When destructed, it restores them back to
   /// the way they used to be.  This is used to handle __extension__ in the

clang/lib/Sema/Sema.cpp

@@ -18,6 +18,7 @@
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/SmallSet.h"
 #include "llvm/ADT/APFloat.h"
+#include "llvm/Support/CrashRecoveryContext.h"
 #include "clang/Sema/CXXFieldCollector.h"
 #include "clang/Sema/TemplateDeduction.h"
 #include "clang/Sema/ExternalSemaSource.h"
@@ -201,7 +202,6 @@ Sema::~Sema() {
     ExternalSema->ForgetSema();
 }
 
-
 /// makeUnavailableInSystemHeader - There is an error in the current
 /// context.  If we're still in a system header, and we can plausibly
 /// make the relevant declaration unavailable instead of erroring, do
@@ -426,6 +426,9 @@ void Sema::LoadExternalWeakUndeclaredIdentifiers() {
 /// translation unit when EOF is reached and all but the top-level scope is
 /// popped.
 void Sema::ActOnEndOfTranslationUnit() {
+  assert(DelayedDiagnostics.getCurrentPool() == NULL
+         && "reached end of translation unit with a pool attached?");
+
   // Only complete translation units define vtables and perform implicit
   // instantiations.
   if (TUKind == TU_Complete) {

clang/lib/Sema/SemaDeclAttr.cpp

@@ -4198,57 +4198,30 @@ static void handleDelayedForbiddenType(Sema &S, DelayedDiagnostic &diag,
   diag.Triggered = true;
 }
 
-// This duplicates a vector push_back but hides the need to know the
+void Sema::PopParsingDeclaration(ParsingDeclState state, Decl *decl) {
-// size of the type.
+  assert(DelayedDiagnostics.getCurrentPool());
-void Sema::DelayedDiagnostics::add(const DelayedDiagnostic &diag) {
+  sema::DelayedDiagnosticPool &poppedPool =
-  assert(StackSize <= StackCapacity);
+    *DelayedDiagnostics.getCurrentPool();
+  DelayedDiagnostics.popWithoutEmitting(state);
 
-  // Grow the stack if necessary.
+  // When delaying diagnostics to run in the context of a parsed
-  if (StackSize == StackCapacity) {
+  // declaration, we only want to actually emit anything if parsing
-    unsigned newCapacity = 2 * StackCapacity + 2;
+  // succeeds.
-    char *newBuffer = new char[newCapacity * sizeof(DelayedDiagnostic)];
+  if (!decl) return;
-    const char *oldBuffer = (const char*) Stack;
 
-    if (StackCapacity)
+  // We emit all the active diagnostics in this pool or any of its
-      memcpy(newBuffer, oldBuffer, StackCapacity * sizeof(DelayedDiagnostic));
+  // parents.  In general, we'll get one pool for the decl spec
-    
+  // and a child pool for each declarator; in a decl group like:
-    delete[] oldBuffer;
+  //   deprecated_typedef foo, *bar, baz();
-    Stack = reinterpret_cast<sema::DelayedDiagnostic*>(newBuffer);
+  // only the declarator pops will be passed decls.  This is correct;
-    StackCapacity = newCapacity;
+  // we really do need to consider delayed diagnostics from the decl spec
-  }
+  // for each of the different declarations.
-
+  const sema::DelayedDiagnosticPool *pool = &poppedPool;
-  assert(StackSize < StackCapacity);
+  do {
-  new (&Stack[StackSize++]) DelayedDiagnostic(diag);
+    for (sema::DelayedDiagnosticPool::pool_iterator
-}
+           i = pool->pool_begin(), e = pool->pool_end(); i != e; ++i) {
-
+      // This const_cast is a bit lame.  Really, Triggered should be mutable.
-void Sema::DelayedDiagnostics::popParsingDecl(Sema &S, ParsingDeclState state,
+      DelayedDiagnostic &diag = const_cast<DelayedDiagnostic&>(*i);
-                                              Decl *decl) {
-  DelayedDiagnostics &DD = S.DelayedDiagnostics;
-
-  // Check the invariants.
-  assert(DD.StackSize >= state.SavedStackSize);
-  assert(state.SavedStackSize >= DD.ActiveStackBase);
-  assert(DD.ParsingDepth > 0);
-
-  // Drop the parsing depth.
-  DD.ParsingDepth--;
-
-  // If there are no active diagnostics, we're done.
-  if (DD.StackSize == DD.ActiveStackBase)
-    return;
-
-  // We only want to actually emit delayed diagnostics when we
-  // successfully parsed a decl.
-  if (decl) {
-    // We emit all the active diagnostics, not just those starting
-    // from the saved state.  The idea is this:  we get one push for a
-    // decl spec and another for each declarator;  in a decl group like:
-    //   deprecated_typedef foo, *bar, baz();
-    // only the declarator pops will be passed decls.  This is correct;
-    // we really do need to consider delayed diagnostics from the decl spec
-    // for each of the different declarations.
-    for (unsigned i = DD.ActiveStackBase, e = DD.StackSize; i != e; ++i) {
-      DelayedDiagnostic &diag = DD.Stack[i];
       if (diag.Triggered)
         continue;
 
@@ -4256,25 +4229,19 @@ void Sema::DelayedDiagnostics::popParsingDecl(Sema &S, ParsingDeclState state,
       case DelayedDiagnostic::Deprecation:
         // Don't bother giving deprecation diagnostics if the decl is invalid.
         if (!decl->isInvalidDecl())
-          S.HandleDelayedDeprecationCheck(diag, decl);
+          HandleDelayedDeprecationCheck(diag, decl);
         break;
 
       case DelayedDiagnostic::Access:
-        S.HandleDelayedAccessCheck(diag, decl);
+        HandleDelayedAccessCheck(diag, decl);
         break;
 
       case DelayedDiagnostic::ForbiddenType:
-        handleDelayedForbiddenType(S, diag, decl);
+        handleDelayedForbiddenType(*this, diag, decl);
         break;
       }
     }
-  }
+  } while ((pool = pool->getParent()));
-
-  // Destroy all the delayed diagnostics we're about to pop off.
-  for (unsigned i = state.SavedStackSize, e = DD.StackSize; i != e; ++i)
-    DD.Stack[i].Destroy();
-
-  DD.StackSize = state.SavedStackSize;
 }
 
 static bool isDeclDeprecated(Decl *D) {