Change how we suppress access control in explicit instantiations

so that we actually accumulate all the delayed diagnostics.  Do
this so that we can restore those diagnostics to good standing
if it turns out that we were wrong to suppress, e.g. if the
tag specifier is actually an elaborated type specifier and not
a declaration.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@156291 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 36 insertions, 24 deletions

diff --git a/lib/Parse/ParseDecl.cpp b/lib/Parse/ParseDecl.cpp
index dbf35b14cf..7cb6474678 100644
--- a/lib/Parse/ParseDecl.cpp
+++ b/lib/Parse/ParseDecl.cpp
@@ -2773,12 +2773,16 @@ void Parser::ParseEnumSpecifier(SourceLocation StartLoc, DeclSpec &DS,
     ScopedEnumKWLoc = ConsumeToken();
   }
 
-  // C++11 [temp.explicit]p12: The usual access controls do not apply to names
-  // used to specify explicit instantiations. We extend this to also cover
-  // explicit specializations.
-  Sema::SuppressAccessChecksRAII SuppressAccess(Actions,
-    TemplateInfo.Kind == ParsedTemplateInfo::ExplicitInstantiation ||
-    TemplateInfo.Kind == ParsedTemplateInfo::ExplicitSpecialization);
+  // C++11 [temp.explicit]p12:
+  //   The usual access controls do not apply to names used to specify
+  //   explicit instantiations.
+  // We extend this to also cover explicit specializations.  Note that
+  // we don't suppress if this turns out to be an elaborated type
+  // specifier.
+  bool shouldDelayDiagsInTag =
+    (TemplateInfo.Kind == ParsedTemplateInfo::ExplicitInstantiation ||
+     TemplateInfo.Kind == ParsedTemplateInfo::ExplicitSpecialization);
+  SuppressAccessChecks diagsFromTag(*this, shouldDelayDiagsInTag);
 
   // If attributes exist after tag, parse them.
   ParsedAttributes attrs(AttrFactory);
@@ -2842,8 +2846,10 @@ void Parser::ParseEnumSpecifier(SourceLocation StartLoc, DeclSpec &DS,
     IsScopedUsingClassTag = false;
   }
 
-  // Stop suppressing access control now we've parsed the enum name.
-  SuppressAccess.done();
+  // Okay, end the suppression area.  We'll decide whether to emit the
+  // diagnostics in a second.
+  if (shouldDelayDiagsInTag)
+    diagsFromTag.done();
 
   TypeResult BaseType;
 
@@ -2925,16 +2931,29 @@ void Parser::ParseEnumSpecifier(SourceLocation StartLoc, DeclSpec &DS,
   // enum foo {..};  void bar() { enum foo x; }  <- use of old foo.
   //
   Sema::TagUseKind TUK;
-  if (DS.isFriendSpecified())
-    TUK = Sema::TUK_Friend;
-  else if (!AllowDeclaration)
+  if (!AllowDeclaration) {
     TUK = Sema::TUK_Reference;
-  else if (Tok.is(tok::l_brace))
-    TUK = Sema::TUK_Definition;
-  else if (Tok.is(tok::semi) && DSC != DSC_type_specifier)
-    TUK = Sema::TUK_Declaration;
-  else
+  } else if (Tok.is(tok::l_brace)) {
+    if (DS.isFriendSpecified()) {
+      Diag(Tok.getLocation(), diag::err_friend_decl_defines_type)
+        << SourceRange(DS.getFriendSpecLoc());
+      ConsumeBrace();
+      SkipUntil(tok::r_brace);
+      TUK = Sema::TUK_Friend;
+    } else {
+      TUK = Sema::TUK_Definition;
+    }
+  } else if (Tok.is(tok::semi) && DSC != DSC_type_specifier) {
+    TUK = (DS.isFriendSpecified() ? Sema::TUK_Friend : Sema::TUK_Declaration);
+  } else {
     TUK = Sema::TUK_Reference;
+  }
+
+  // If this is an elaborated type specifier, and we delayed
+  // diagnostics before, just merge them into the current pool.
+  if (TUK == Sema::TUK_Reference && shouldDelayDiagsInTag) {
+    diagsFromTag.redelay();
+  }
 
   MultiTemplateParamsArg TParams;
   if (TemplateInfo.Kind != ParsedTemplateInfo::NonTemplate &&
@@ -3014,14 +3033,7 @@ void Parser::ParseEnumSpecifier(SourceLocation StartLoc, DeclSpec &DS,
   }
 
   if (Tok.is(tok::l_brace) && TUK != Sema::TUK_Reference) {
-    if (TUK == Sema::TUK_Friend) {
-      Diag(Tok, diag::err_friend_decl_defines_type)
-        << SourceRange(DS.getFriendSpecLoc());
-      ConsumeBrace();
-      SkipUntil(tok::r_brace);
-    } else {
-      ParseEnumBody(StartLoc, TagDecl);
-    }
+    ParseEnumBody(StartLoc, TagDecl);
   }
 
   if (DS.SetTypeSpecType(DeclSpec::TST_enum, StartLoc,