Reapply r151638 and r151641.

The bug that was caught by Apple's internal buildbots was valid and also showed another bug in my implementation.

These are now fixed, with regression tests added to catch them both (not Darwin-specific).

Original log:
====================

Revert r151638 because it causes assertion hit on PCH creation for Cocoa.h

Original log:
---------------------
Correctly track tags and enum members defined in the prototype of a function, and ensure they are properly scoped.

This fixes code such as:

enum e {x, y};
int f(enum {y, x} n) {
 return 0;
}

This finally fixes PR5464 and PR5477.
---------------------

I also reverted r151641 which was enhancement on top of r151638.

====================




git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@151712 91177308-0d34-0410-b5e6-96231b3b80d8

5 files changed, 33 insertions, 1 deletions

diff --git a/include/clang/AST/Decl.h b/include/clang/AST/Decl.h
index c99ad115cf..1338657ff4 100644
--- a/include/clang/AST/Decl.h
+++ b/include/clang/AST/Decl.h
@@ -1431,6 +1431,11 @@ private:
   /// no formals.
   ParmVarDecl **ParamInfo;
 
+  /// DeclsInPrototypeScope - Array of pointers to NamedDecls for
+  /// decls defined in the function prototype that are not parameters. E.g.
+  /// 'enum Y' in 'void f(enum Y {AA} x) {}'.
+  llvm::ArrayRef<NamedDecl*> DeclsInPrototypeScope;
+
   LazyDeclStmtPtr Body;
 
   // FIXME: This can be packed into the bitfields in Decl.
@@ -1796,6 +1801,11 @@ public:
     setParams(getASTContext(), NewParamInfo);
   }
 
+  const llvm::ArrayRef<NamedDecl*> &getDeclsInPrototypeScope() const {
+    return DeclsInPrototypeScope;
+  }
+  void setDeclsInPrototypeScope(llvm::ArrayRef<NamedDecl *> NewDecls);
+
   /// getMinRequiredArguments - Returns the minimum number of arguments
   /// needed to call this function. This may be fewer than the number of
   /// function parameters, if some of the parameters have default
diff --git a/include/clang/Basic/DiagnosticGroups.td b/include/clang/Basic/DiagnosticGroups.td
index 7b45a9a71c..f175b39d70 100644
--- a/include/clang/Basic/DiagnosticGroups.td
+++ b/include/clang/Basic/DiagnosticGroups.td
@@ -244,6 +244,7 @@ def VectorConversions : DiagGroup<"vector-conversions">;      // clang specific
 def VexingParse : DiagGroup<"vexing-parse">;
 def VLA : DiagGroup<"vla">;
 def VolatileRegisterVar : DiagGroup<"volatile-register-var">;
+def Visibility : DiagGroup<"visibility">;
 
 // GCC calls -Wdeprecated-writable-strings -Wwrite-strings.
 def GCCWriteStrings : DiagGroup<"write-strings" , [DeprecatedWritableStr]>;
diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index c347c2e002..78d1d8d3d4 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -132,7 +132,11 @@ def warn_unused_variable : Warning<"unused variable %0">,
 def warn_unused_exception_param : Warning<"unused exception parameter %0">,
   InGroup<UnusedExceptionParameter>, DefaultIgnore;
 def warn_decl_in_param_list : Warning<
-  "declaration of %0 will not be visible outside of this function">;
+  "declaration of %0 will not be visible outside of this function">,
+  InGroup<Visibility>;
+def warn_redefinition_in_param_list : Warning<
+  "redefinition of %0 will not be visible outside of this function">,
+  InGroup<Visibility>;
 def warn_empty_parens_are_function_decl : Warning<
   "empty parentheses interpreted as a function declaration">,
   InGroup<VexingParse>;
diff --git a/include/clang/Sema/Scope.h b/include/clang/Sema/Scope.h
index 9b3dd9299d..e9aa173cb9 100644
--- a/include/clang/Sema/Scope.h
+++ b/include/clang/Sema/Scope.h
@@ -297,6 +297,10 @@ public:
   /// \brief Determine whether this scope is a C++ 'try' block.
   bool isTryScope() const { return getFlags() & Scope::TryScope; }
 
+  /// containedInPrototypeScope - Return true if this or a parent scope
+  /// is a FunctionPrototypeScope.
+  bool containedInPrototypeScope() const;
+
   typedef UsingDirectivesTy::iterator udir_iterator;
   typedef UsingDirectivesTy::const_iterator const_udir_iterator;
 
diff --git a/include/clang/Sema/Sema.h b/include/clang/Sema/Sema.h
index 499ee31d4a..d7ff5491f8 100644
--- a/include/clang/Sema/Sema.h
+++ b/include/clang/Sema/Sema.h
@@ -902,6 +902,17 @@ public:
   // Symbol table / Decl tracking callbacks: SemaDecl.cpp.
   //
 
+  /// List of decls defined in a function prototype. This contains EnumConstants
+  /// that incorrectly end up in translation unit scope because there is no
+  /// function to pin them on. ActOnFunctionDeclarator reads this list and patches
+  /// them into the FunctionDecl.
+  std::vector<NamedDecl*> DeclsInPrototypeScope;
+  /// Nonzero if we are currently parsing a function declarator. This is a counter
+  /// as opposed to a boolean so we can deal with nested function declarators
+  /// such as:
+  ///     void f(void (*g)(), ...)
+  unsigned InFunctionDeclarator;
+
   DeclGroupPtrTy ConvertDeclToDeclGroup(Decl *Ptr, Decl *OwnedType = 0);
 
   void DiagnoseUseOfUnimplementedSelectors();
@@ -1048,6 +1059,8 @@ public:
   // Returns true if the variable declaration is a redeclaration
   bool CheckVariableDeclaration(VarDecl *NewVD, LookupResult &Previous);
   void CheckCompleteVariableDeclaration(VarDecl *var);
+  void ActOnStartFunctionDeclarator();
+  void ActOnEndFunctionDeclarator();
   NamedDecl* ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC,
                                      TypeSourceInfo *TInfo,
                                      LookupResult &Previous,