1 files changed, 126 insertions, 37 deletions

diff --git a/include/clang/AST/DeclBase.h b/include/clang/AST/DeclBase.h
index 754facf..26eea64 100644
--- a/include/clang/AST/DeclBase.h
+++ b/include/clang/AST/DeclBase.h
@@ -16,6 +16,7 @@
 
 #include "clang/AST/AttrIterator.h"
 #include "clang/AST/DeclarationName.h"
+#include "clang/Basic/Linkage.h"
 #include "clang/Basic/Specifiers.h"
 #include "llvm/ADT/PointerUnion.h"
 #include "llvm/Support/Compiler.h"
@@ -31,6 +32,7 @@ class DeclarationName;
 class DependentDiagnostic;
 class EnumDecl;
 class FunctionDecl;
+class LinkageComputer;
 class LinkageSpecDecl;
 class Module;
 class NamedDecl;
@@ -157,7 +159,12 @@ public:
     /// This declaration is a C++ operator declared in a non-class
     /// context.  All such operators are also in IDNS_Ordinary.
     /// C++ lexical operator lookup looks for these.
-    IDNS_NonMemberOperator   = 0x0400
+    IDNS_NonMemberOperator   = 0x0400,
+
+    /// This declaration is a function-local extern declaration of a
+    /// variable or function. This may also be IDNS_Ordinary if it
+    /// has been declared outside any function.
+    IDNS_LocalExtern         = 0x0800
   };
 
   /// ObjCDeclQualifier - 'Qualifiers' written next to the return and
@@ -284,19 +291,16 @@ protected:
   /// IdentifierNamespace - This specifies what IDNS_* namespace this lives in.
   unsigned IdentifierNamespace : 12;
 
-  /// \brief Whether the \c CachedLinkage field is active.
-  ///
-  /// This field is only valid for NamedDecls subclasses.
-  mutable unsigned HasCachedLinkage : 1;
-
-  /// \brief If \c HasCachedLinkage, the linkage of this declaration.
-  ///
-  /// This field is only valid for NamedDecls subclasses.
-  mutable unsigned CachedLinkage : 2;
+  /// \brief If 0, we have not computed the linkage of this declaration.
+  /// Otherwise, it is the linkage + 1.
+  mutable unsigned CacheValidAndLinkage : 3;
 
   friend class ASTDeclWriter;
   friend class ASTDeclReader;
   friend class ASTReader;
+  friend class LinkageComputer;
+
+  template<typename decl_type> friend class Redeclarable;
 
 private:
   void CheckAccessDeclContext() const;
@@ -309,7 +313,7 @@ protected:
       HasAttrs(false), Implicit(false), Used(false), Referenced(false),
       Access(AS_none), FromASTFile(0), Hidden(0),
       IdentifierNamespace(getIdentifierNamespaceForKind(DK)),
-      HasCachedLinkage(0)
+      CacheValidAndLinkage(0)
   {
     if (StatisticsEnabled) add(DK);
   }
@@ -319,7 +323,7 @@ protected:
       HasAttrs(false), Implicit(false), Used(false), Referenced(false),
       Access(AS_none), FromASTFile(0), Hidden(0),
       IdentifierNamespace(getIdentifierNamespaceForKind(DK)),
-      HasCachedLinkage(0)
+      CacheValidAndLinkage(0)
   {
     if (StatisticsEnabled) add(DK);
   }
@@ -341,6 +345,18 @@ protected:
   /// \brief Update a potentially out-of-date declaration.
   void updateOutOfDate(IdentifierInfo &II) const;
 
+  Linkage getCachedLinkage() const {
+    return Linkage(CacheValidAndLinkage - 1);
+  }
+
+  void setCachedLinkage(Linkage L) const {
+    CacheValidAndLinkage = L + 1;
+  }
+
+  bool hasCachedLinkage() const {
+    return CacheValidAndLinkage;
+  }
+
 public:
 
   /// \brief Source range that this declaration covers.
@@ -419,7 +435,6 @@ public:
     return const_cast<AttrVec&>(const_cast<const Decl*>(this)->getAttrs());
   }
   const AttrVec &getAttrs() const;
-  void swapAttrs(Decl *D);
   void dropAttrs();
 
   void addAttr(Attr *A) {
@@ -490,7 +505,16 @@ public:
   /// whether the function is used.
   bool isUsed(bool CheckUsedAttr = true) const;
 
-  void setUsed(bool U = true) { Used = U; }
+  /// \brief Set whether the declaration is used, in the sense of odr-use.
+  ///
+  /// This should only be used immediately after creating a declaration.
+  void setIsUsed() { Used = true; }
+
+  /// \brief Mark the declaration used, in the sense of odr-use.
+  ///
+  /// This notifies any mutation listeners in addition to setting a bit
+  /// indicating the declaration is used.
+  void markUsed(ASTContext &C);
 
   /// \brief Whether this declaration was referenced.
   bool isReferenced() const;
@@ -513,13 +537,13 @@ public:
     NextInContextAndBits.setInt(Bits);
   }
 
-protected:
   /// \brief Whether this declaration was marked as being private to the
   /// module in which it was defined.
-  bool isModulePrivate() const { 
+  bool isModulePrivate() const {
     return NextInContextAndBits.getInt() & ModulePrivateFlag;
   }
-  
+
+protected:
   /// \brief Specify whether this declaration was marked as being private
   /// to the module in which it was defined.
   void setModulePrivate(bool MP = true) {
@@ -761,7 +785,12 @@ public:
   const Decl *getPreviousDecl() const { 
     return const_cast<Decl *>(this)->getPreviousDeclImpl();
   }
-  
+
+  /// \brief True if this is the first declaration in its redeclaration chain.
+  bool isFirstDecl() const {
+    return getPreviousDecl() == 0;
+  }
+
   /// \brief Retrieve the most recent declaration that declares the same entity
   /// as this declaration (which may be this declaration).
   Decl *getMostRecentDecl() { return getMostRecentDeclImpl(); }
@@ -777,8 +806,10 @@ public:
   ///  top-level Stmt* of that body.  Otherwise this method returns null.
   virtual Stmt* getBody() const { return 0; }
 
-  /// \brief Returns true if this Decl represents a declaration for a body of
+  /// \brief Returns true if this \c Decl represents a declaration for a body of
   /// code, such as a function or method definition.
+  /// Note that \c hasBody can also return true if any redeclaration of this
+  /// \c Decl represents a declaration for a body of code.
   virtual bool hasBody() const { return getBody() != 0; }
 
   /// getBodyRBrace - Gets the right brace of the body, if a body exists.
@@ -808,37 +839,71 @@ public:
   bool isFunctionOrFunctionTemplate() const;
 
   /// \brief Changes the namespace of this declaration to reflect that it's
+  /// a function-local extern declaration.
+  ///
+  /// These declarations appear in the lexical context of the extern
+  /// declaration, but in the semantic context of the enclosing namespace
+  /// scope.
+  void setLocalExternDecl() {
+    assert((IdentifierNamespace == IDNS_Ordinary ||
+            IdentifierNamespace == IDNS_OrdinaryFriend) &&
+           "namespace is not ordinary");
+
+    Decl *Prev = getPreviousDecl();
+    IdentifierNamespace &= ~IDNS_Ordinary;
+
+    IdentifierNamespace |= IDNS_LocalExtern;
+    if (Prev && Prev->getIdentifierNamespace() & IDNS_Ordinary)
+      IdentifierNamespace |= IDNS_Ordinary;
+  }
+
+  /// \brief Determine whether this is a block-scope declaration with linkage.
+  /// This will either be a local variable declaration declared 'extern', or a
+  /// local function declaration.
+  bool isLocalExternDecl() {
+    return IdentifierNamespace & IDNS_LocalExtern;
+  }
+
+  /// \brief Changes the namespace of this declaration to reflect that it's
   /// the object of a friend declaration.
   ///
   /// These declarations appear in the lexical context of the friending
   /// class, but in the semantic context of the actual entity.  This property
   /// applies only to a specific decl object;  other redeclarations of the
   /// same entity may not (and probably don't) share this property.
-  void setObjectOfFriendDecl(bool PreviouslyDeclared) {
+  void setObjectOfFriendDecl(bool PerformFriendInjection = false) {
     unsigned OldNS = IdentifierNamespace;
     assert((OldNS & (IDNS_Tag | IDNS_Ordinary |
-                     IDNS_TagFriend | IDNS_OrdinaryFriend)) &&
+                     IDNS_TagFriend | IDNS_OrdinaryFriend |
+                     IDNS_LocalExtern)) &&
            "namespace includes neither ordinary nor tag");
     assert(!(OldNS & ~(IDNS_Tag | IDNS_Ordinary | IDNS_Type |
-                       IDNS_TagFriend | IDNS_OrdinaryFriend)) &&
+                       IDNS_TagFriend | IDNS_OrdinaryFriend |
+                       IDNS_LocalExtern)) &&
            "namespace includes other than ordinary or tag");
 
-    IdentifierNamespace = 0;
+    Decl *Prev = getPreviousDecl();
+    IdentifierNamespace &= ~(IDNS_Ordinary | IDNS_Tag | IDNS_Type);
+
     if (OldNS & (IDNS_Tag | IDNS_TagFriend)) {
       IdentifierNamespace |= IDNS_TagFriend;
-      if (PreviouslyDeclared) IdentifierNamespace |= IDNS_Tag | IDNS_Type;
+      if (PerformFriendInjection ||
+          (Prev && Prev->getIdentifierNamespace() & IDNS_Tag))
+        IdentifierNamespace |= IDNS_Tag | IDNS_Type;
     }
 
-    if (OldNS & (IDNS_Ordinary | IDNS_OrdinaryFriend)) {
+    if (OldNS & (IDNS_Ordinary | IDNS_OrdinaryFriend | IDNS_LocalExtern)) {
       IdentifierNamespace |= IDNS_OrdinaryFriend;
-      if (PreviouslyDeclared) IdentifierNamespace |= IDNS_Ordinary;
+      if (PerformFriendInjection ||
+          (Prev && Prev->getIdentifierNamespace() & IDNS_Ordinary))
+        IdentifierNamespace |= IDNS_Ordinary;
     }
   }
 
   enum FriendObjectKind {
-    FOK_None, // not a friend object
-    FOK_Declared, // a friend of a previously-declared entity
-    FOK_Undeclared // a friend of a previously-undeclared entity
+    FOK_None,      ///< Not a friend object.
+    FOK_Declared,  ///< A friend of a previously-declared entity.
+    FOK_Undeclared ///< A friend of a previously-undeclared entity.
   };
 
   /// \brief Determines whether this declaration is the object of a
@@ -846,11 +911,11 @@ public:
   ///
   /// There is currently no direct way to find the associated FriendDecl.
   FriendObjectKind getFriendObjectKind() const {
-    unsigned mask
-      = (IdentifierNamespace & (IDNS_TagFriend | IDNS_OrdinaryFriend));
+    unsigned mask =
+        (IdentifierNamespace & (IDNS_TagFriend | IDNS_OrdinaryFriend));
     if (!mask) return FOK_None;
-    return (IdentifierNamespace & (IDNS_Tag | IDNS_Ordinary) ?
-              FOK_Declared : FOK_Undeclared);
+    return (IdentifierNamespace & (IDNS_Tag | IDNS_Ordinary) ? FOK_Declared
+                                                             : FOK_Undeclared);
   }
 
   /// Specifies that this declaration is a C++ overloaded non-member.
@@ -877,9 +942,6 @@ public:
   // Same as dump(), but forces color printing.
   LLVM_ATTRIBUTE_USED void dumpColor() const;
   void dump(raw_ostream &Out) const;
-  // Debuggers don't usually respect default arguments.
-  LLVM_ATTRIBUTE_USED void dumpXML() const;
-  void dumpXML(raw_ostream &OS) const;
 
 private:
   void setAttrsImpl(const AttrVec& Attrs, ASTContext &Ctx);
@@ -974,6 +1036,7 @@ protected:
   mutable Decl *LastDecl;
 
   friend class ExternalASTSource;
+  friend class ASTDeclReader;
   friend class ASTWriter;
 
   /// \brief Build up a chain of declarations.
@@ -1096,6 +1159,14 @@ public:
   /// C++0x scoped enums), and C++ linkage specifications.
   bool isTransparentContext() const;
 
+  /// \brief Determines whether this context or some of its ancestors is a
+  /// linkage specification context that specifies C linkage.
+  bool isExternCContext() const;
+
+  /// \brief Determines whether this context or some of its ancestors is a
+  /// linkage specification context that specifies C++ linkage.
+  bool isExternCXXContext() const;
+
   /// \brief Determine whether this declaration context is equivalent
   /// to the declaration context DC.
   bool Equals(const DeclContext *DC) const {
@@ -1429,12 +1500,20 @@ public:
     return const_cast<DeclContext*>(this)->lookup(Name);
   }
 
+  /// \brief Find the declarations with the given name that are visible
+  /// within this context; don't attempt to retrieve anything from an
+  /// external source.
+  lookup_result noload_lookup(DeclarationName Name);
+
   /// \brief A simplistic name lookup mechanism that performs name lookup
   /// into this declaration context without consulting the external source.
   ///
   /// This function should almost never be used, because it subverts the
   /// usual relationship between a DeclContext and the external source.
   /// See the ASTImporter for the (few, but important) use cases.
+  ///
+  /// FIXME: This is very inefficient; replace uses of it with uses of
+  /// noload_lookup.
   void localUncachedLookup(DeclarationName Name,
                            SmallVectorImpl<NamedDecl *> &Results);
 
@@ -1458,10 +1537,16 @@ public:
   /// of looking up every possible name.
   class all_lookups_iterator;
 
+  /// \brief Iterators over all possible lookups within this context.
   all_lookups_iterator lookups_begin() const;
-
   all_lookups_iterator lookups_end() const;
 
+  /// \brief Iterators over all possible lookups within this context that are
+  /// currently loaded; don't attempt to retrieve anything from an external
+  /// source.
+  all_lookups_iterator noload_lookups_begin() const;
+  all_lookups_iterator noload_lookups_end() const;
+
   /// udir_iterator - Iterates through the using-directives stored
   /// within this context.
   typedef UsingDirectiveDecl * const * udir_iterator;
@@ -1532,6 +1617,8 @@ public:
   static bool classof(const DeclContext *D) { return true; }
 
   LLVM_ATTRIBUTE_USED void dumpDeclContext() const;
+  LLVM_ATTRIBUTE_USED void dumpLookups() const;
+  LLVM_ATTRIBUTE_USED void dumpLookups(llvm::raw_ostream &OS) const;
 
 private:
   void reconcileExternalVisibleStorage();
@@ -1548,6 +1635,8 @@ private:
   friend class DependentDiagnostic;
   StoredDeclsMap *CreateStoredDeclsMap(ASTContext &C) const;
 
+  template<decl_iterator (DeclContext::*Begin)() const,
+           decl_iterator (DeclContext::*End)() const>
   void buildLookupImpl(DeclContext *DCtx);
   void makeDeclVisibleInContextWithFlags(NamedDecl *D, bool Internal,
                                          bool Rediscoverable);