When we parse a tag specifier, keep track of whether that tag

specifier resulted in the creation of a new TagDecl node, which
happens either when the tag specifier was a definition or when the tag
specifier was the first declaration of that tag type. This information
has several uses, the first of which is implemented in this commit:

  1) In C++, one is not allowed to define tag types within a type
  specifier (e.g., static_cast<struct S { int x; } *>(0) is
  ill-formed) or within the result or parameter types of a
  function. We now diagnose this.

  2) We can extend DeclGroups to contain information about any tags
  that are declared/defined within the declaration specifiers of a
  variable, e.g.,

    struct Point { int x, y, z; } p;

  This will help improve AST printing and template instantiation,
  among other things.

  3) For C99, we can keep track of whether a tag type is defined
  within the type of a parameter, to properly cope with cases like,
  e.g.,

    int bar(struct T2 { int x; } y) {
      struct T2 z;
    }

  We can also do similar things wherever there is a type specifier,
  e.g., to keep track of where the definition of S occurs in this
  legal C99 code:

    (struct S { int x, y; } *)0

  



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@72555 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 10 insertions, 5 deletions

diff --git a/lib/Parse/DeclSpec.cpp b/lib/Parse/DeclSpec.cpp
index e592deecd0..2a765d2124 100644
--- a/lib/Parse/DeclSpec.cpp
+++ b/lib/Parse/DeclSpec.cpp
@@ -241,12 +241,14 @@ bool DeclSpec::SetTypeSpecSign(TSS S, SourceLocation Loc,
 }
 
 bool DeclSpec::SetTypeSpecType(TST T, SourceLocation Loc,
-                               const char *&PrevSpec, void *Rep) {
+                               const char *&PrevSpec, void *Rep,
+                               bool Owned) {
   if (TypeSpecType != TST_unspecified)
     return BadSpecifier((TST)TypeSpecType, PrevSpec);
   TypeSpecType = T;
   TypeRep = Rep;
   TSTLoc = Loc;
+  TypeSpecOwned = Owned;
   return false;
 }
 
diff --git a/lib/Parse/ParseDecl.cpp b/lib/Parse/ParseDecl.cpp
index 59e9555a88..54e70be16e 100644
--- a/lib/Parse/ParseDecl.cpp
+++ b/lib/Parse/ParseDecl.cpp
@@ -1460,8 +1460,10 @@ void Parser::ParseEnumSpecifier(SourceLocation StartLoc, DeclSpec &DS,
     TK = Action::TK_Declaration;
   else
     TK = Action::TK_Reference;
+  bool Owned = false;
   DeclPtrTy TagDecl = Actions.ActOnTag(CurScope, DeclSpec::TST_enum, TK,
-                                       StartLoc, SS, Name, NameLoc, Attr, AS);
+                                       StartLoc, SS, Name, NameLoc, Attr, AS,
+                                       Owned);
   
   if (Tok.is(tok::l_brace))
     ParseEnumBody(StartLoc, TagDecl);
@@ -1469,7 +1471,7 @@ void Parser::ParseEnumSpecifier(SourceLocation StartLoc, DeclSpec &DS,
   // TODO: semantic analysis on the declspec for enums.
   const char *PrevSpec = 0;
   if (DS.SetTypeSpecType(DeclSpec::TST_enum, StartLoc, PrevSpec,
-                         TagDecl.getAs<void>()))
+                         TagDecl.getAs<void>(), Owned))
     Diag(StartLoc, diag::err_invalid_decl_spec_combination) << PrevSpec;
 }
 
diff --git a/lib/Parse/ParseDeclCXX.cpp b/lib/Parse/ParseDeclCXX.cpp
index a7d3b52bd2..cfbd9097f7 100644
--- a/lib/Parse/ParseDeclCXX.cpp
+++ b/lib/Parse/ParseDeclCXX.cpp
@@ -479,6 +479,7 @@ void Parser::ParseClassSpecifier(tok::TokenKind TagTokKind,
   // FIXME: When TK == TK_Reference and we have a template-id, we need
   // to turn that template-id into a type.
 
+  bool Owned = false;
   if (TemplateId && TK != Action::TK_Reference) {
     // Explicit specialization, class template partial specialization,
     // or explicit instantiation.
@@ -582,7 +583,7 @@ void Parser::ParseClassSpecifier(tok::TokenKind TagTokKind,
 
     // Declaration or definition of a class type
     TagOrTempResult = Actions.ActOnTag(CurScope, TagType, TK, StartLoc, SS, 
-                                       Name, NameLoc, Attr, AS);
+                                       Name, NameLoc, Attr, AS, Owned);
   }
 
   // Parse the optional base clause (C++ only).
@@ -608,7 +609,7 @@ void Parser::ParseClassSpecifier(tok::TokenKind TagTokKind,
   }
   
   if (DS.SetTypeSpecType(TagType, StartLoc, PrevSpec, 
-                         TagOrTempResult.get().getAs<void>()))
+                         TagOrTempResult.get().getAs<void>(), Owned))
     Diag(StartLoc, diag::err_invalid_decl_spec_combination) << PrevSpec;
   
   if (DS.isFriendSpecified())