From: Peter Collingbourne <peter@pcc.me.uk>
Date: Sat, 22 Feb 2014 03:05:49 +0000 (+0000)
Subject: Do not add enums to prototype scope in C++ modes.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=3d8ada65463bb8f60bfa08964050e40eab1caa36;p=clang

Do not add enums to prototype scope in C++ modes.

The language forbids defining enums in prototypes, so this check is normally
redundant, but if an enum is defined during template instantiation it should
not be added to the prototype scope.

While at it, clean up the code that deals with tag definitions in prototype
scope and expand the visibility warning to cover the case where an anonymous
enum is defined.

Differential Revision: http://llvm-reviews.chandlerc.com/D2742

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@201927 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Sema/Sema.h b/include/clang/Sema/Sema.h
index 14eb7ad560..7c920581db 100644
--- a/include/clang/Sema/Sema.h
+++ b/include/clang/Sema/Sema.h
@@ -1512,8 +1512,6 @@ public:
   void CheckVariableDeclarationType(VarDecl *NewVD);
   void CheckCompleteVariableDeclaration(VarDecl *var);
   void MaybeSuggestAddingStaticToDecl(const FunctionDecl *D);
-  void ActOnStartFunctionDeclarator();
-  void ActOnEndFunctionDeclarator();
 
   NamedDecl* ActOnFunctionDeclarator(Scope* S, Declarator& D, DeclContext* DC,
                                      TypeSourceInfo *TInfo,
diff --git a/lib/Parse/ParseDecl.cpp b/lib/Parse/ParseDecl.cpp
index 20ac4df544..8efbc3db39 100644
--- a/lib/Parse/ParseDecl.cpp
+++ b/lib/Parse/ParseDecl.cpp
@@ -5069,7 +5069,6 @@ void Parser::ParseFunctionDeclarator(Declarator &D,
   ParsedAttributes FnAttrs(AttrFactory);
   TypeResult TrailingReturnType;
 
-  Actions.ActOnStartFunctionDeclarator();
   /* LocalEndLoc is the end location for the local FunctionTypeLoc.
      EndLoc is the end location for the function declarator.
      They differ for trailing return types. */
@@ -5198,8 +5197,6 @@ void Parser::ParseFunctionDeclarator(Declarator &D,
                                              StartLoc, LocalEndLoc, D,
                                              TrailingReturnType),
                 FnAttrs, EndLoc);
-
-  Actions.ActOnEndFunctionDeclarator();
 }
 
 /// isFunctionDeclaratorIdentifierList - This parameter list may have an
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index 06d4500f77..8e1871037c 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -1399,15 +1399,6 @@ void Sema::ActOnPopScope(SourceLocation Loc, Scope *S) {
   }
 }
 
-void Sema::ActOnStartFunctionDeclarator() {
-  ++InFunctionDeclarator;
-}
-
-void Sema::ActOnEndFunctionDeclarator() {
-  assert(InFunctionDeclarator);
-  --InFunctionDeclarator;
-}
-
 /// \brief Look for an Objective-C class in the translation unit.
 ///
 /// \param Id The name of the Objective-C class we're looking for. If
@@ -11071,10 +11062,14 @@ CreateNewDecl:
   if (Attr)
     ProcessDeclAttributeList(S, New, Attr);
 
-  // If we're declaring or defining a tag in function prototype scope
-  // in C, note that this type can only be used within the function.
-  if (Name && S->isFunctionPrototypeScope() && !getLangOpts().CPlusPlus)
+  // If we're declaring or defining a tag in function prototype scope in C,
+  // note that this type can only be used within the function and add it to
+  // the list of decls to inject into the function definition scope.
+  if (!getLangOpts().CPlusPlus && (Name || Kind == TTK_Enum) &&
+      getNonFieldDeclScope(S)->isFunctionPrototypeScope()) {
     Diag(Loc, diag::warn_decl_in_param_list) << Context.getTagDeclType(New);
+    DeclsInPrototypeScope.push_back(New);
+  }
 
   // Set the lexical context. If the tag has a C++ scope specifier, the
   // lexical context will be different from the semantic context.
@@ -11124,12 +11119,6 @@ CreateNewDecl:
         II->isStr("FILE"))
       Context.setFILEDecl(New);
 
-  // If we were in function prototype scope (and not in C++ mode), add this
-  // tag to the list of decls to inject into the function definition scope.
-  if (S->isFunctionPrototypeScope() && !getLangOpts().CPlusPlus &&
-      InFunctionDeclarator && Name)
-    DeclsInPrototypeScope.push_back(New);
-
   if (PrevDecl)
     mergeDeclAttributes(New, PrevDecl);
 
@@ -12952,11 +12941,6 @@ void Sema::ActOnEnumBody(SourceLocation EnumLoc, SourceLocation LBraceLoc,
   Enum->completeDefinition(BestType, BestPromotionType,
                            NumPositiveBits, NumNegativeBits);
 
-  // If we're declaring a function, ensure this decl isn't forgotten about -
-  // it needs to go into the function scope.
-  if (InFunctionDeclarator)
-    DeclsInPrototypeScope.push_back(Enum);
-
   CheckForDuplicateEnumValues(*this, Elements, Enum, EnumType);
 
   // Now that the enum type is defined, ensure it's not been underaligned.
diff --git a/test/Sema/decl-in-prototype.c b/test/Sema/decl-in-prototype.c
index 877f887392..9cb7fabab3 100644
--- a/test/Sema/decl-in-prototype.c
+++ b/test/Sema/decl-in-prototype.c
@@ -2,11 +2,11 @@
 
 const int AA = 5;
 
-int f1(enum {AA,BB} E) {
+int f1(enum {AA,BB} E) { // expected-warning {{will not be visible outside of this function}}
     return BB;
 }
 
-int f2(enum {AA=7,BB} E) {
+int f2(enum {AA=7,BB} E) { // expected-warning {{will not be visible outside of this function}}
     return AA;
 }
 
diff --git a/test/SemaTemplate/instantiate-enum.cpp b/test/SemaTemplate/instantiate-enum.cpp
index 5353a92a90..3da8eb4a6c 100644
--- a/test/SemaTemplate/instantiate-enum.cpp
+++ b/test/SemaTemplate/instantiate-enum.cpp
@@ -25,3 +25,18 @@ namespace PR6375 {
 
   template void f<int>();
 }
+
+namespace EnumScoping {
+
+template <typename T>
+class C {
+  enum {
+    value = 42
+  };
+};
+
+void f(int i, C<int>::C c) {
+  int value;
+}
+
+}