simplify parsing by limiting to TypeAttr

Changing the attr base class from DeclOrTypeAttr to TypeAttr allows us
to better isolate the attribute handling logic just in SemaType.cpp in
the handleWrapsAttr() method. Furthermore, check for language
compatibility at this step as well.

Rely on `COnly` to provide the warnings to the user, then silently
discard the attribute.

|	let LangOpts = [COnly];

Signed-off-by: Justin Stitt <[email protected]>

Author: JustinStitt

clang/include/clang/Basic/Attr.td

@@ -4856,14 +4856,14 @@ def ClspvLibclcBuiltin: InheritableAttr {
   let SimpleHandler = 1;
 }
 
-def Wraps : DeclOrTypeAttr {
+def Wraps : TypeAttr {
   let Spellings = [Clang<"wraps">];
   let Subjects = SubjectList<[Var, TypedefName, Field]>;
   let Documentation = [WrapsDocs];
   let LangOpts = [COnly];
 }
 
-def NoWraps : DeclOrTypeAttr {
+def NoWraps : TypeAttr {
   let Spellings = [Clang<"no_wraps">];
   let Subjects = SubjectList<[Var, TypedefName, Field]>;
   let Documentation = [NoWrapsDocs];

clang/lib/Sema/SemaDeclAttr.cpp

@@ -4009,14 +4009,6 @@ void Sema::AddAlignValueAttr(Decl *D, const AttributeCommonInfo &CI, Expr *E) {
   D->addAttr(::new (Context) AlignValueAttr(Context, CI, E));
 }
 
-static void handleWrapsAttr(Sema &S, Decl *D, const ParsedAttr &AL,
-                            bool NoWraps = false) {
-  if (NoWraps)
-    D->addAttr(::new (S.Context) NoWrapsAttr(S.Context, AL));
-  else
-    D->addAttr(::new (S.Context) WrapsAttr(S.Context, AL));
-}
-
 static void handleAlignedAttr(Sema &S, Decl *D, const ParsedAttr &AL) {
   if (AL.hasParsedType()) {
     const ParsedType &TypeArg = AL.getTypeArg();
@@ -6970,12 +6962,6 @@ ProcessDeclAttribute(Sema &S, Scope *scope, Decl *D, const ParsedAttr &AL,
   case ParsedAttr::AT_SizedByOrNull:
     handleCountedByAttrField(S, D, AL);
     break;
-  case ParsedAttr::AT_Wraps:
-    handleWrapsAttr(S, D, AL);
-    break;
-  case ParsedAttr::AT_NoWraps:
-    handleWrapsAttr(S, D, AL, true);
-    break;
 
   // Microsoft attributes:
   case ParsedAttr::AT_LayoutVersion:

clang/lib/Sema/SemaType.cpp

@@ -6541,6 +6541,11 @@ static void handleWrapsAttr(QualType &Type, const ParsedAttr &Attr,
   Sema &S = State.getSema();
   ASTContext &Ctx = S.Context;
 
+  // wraps and no_wraps are most useful and consistent when used with C. Other
+  // languages have better alternatives within their type systems.
+  if (S.LangOpts.CPlusPlus || S.LangOpts.ObjC)
+    return;
+
   if (!Type->isIntegerType()) {
     S.Diag(Attr.getLoc(), diag::warn_wraps_attr_var_decl_type_not_integer)
         << (int)NoWraps << Type.getAsString();