static void HandleDLLImportAttr(Decl *D, const AttributeList &Attr, Sema &S) {
  // Attribute can be applied only to functions or variables.
  FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
  if (!FD && !isa<VarDecl>(D)) {
    // Apparently Visual C++ thinks it is okay to not emit a warning
    // in this case, so only emit a warning when -fms-extensions is not
    // specified.
    if (!S.getLangOpts().MicrosoftExt)
      S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
        << Attr.getName() << 2 /*variable and function*/;
    return;
  }

  // Currently, the dllimport attribute is ignored for inlined functions.
  // Warning is emitted.
  if (FD && FD->isInlineSpecified()) {
    S.Diag(Attr.getLoc(), diag::warn_attribute_ignored) << Attr.getName();
    return;
  }

  unsigned Index = Attr.getAttributeSpellingListIndex();
  DLLImportAttr *NewAttr = S.mergeDLLImportAttr(D, Attr.getRange(), Index);
  if (NewAttr)
    D->addAttr(NewAttr);
}
static void HandleDLLExportAttr(Decl *D, const AttributeList &Attr, Sema &S) {
  // check the attribute arguments.
  if (Attr.getNumArgs() != 0) {
    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
    return;
  }

  // Attribute can be applied only to functions or variables.
  FunctionDecl *FD = dyn_cast<FunctionDecl>(D);
  if (!FD && !isa<VarDecl>(D)) {
    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
      << Attr.getName() << 2 /*variable and function*/;
    return;
  }

  // Currently, the dllexport attribute is ignored for inlined functions, unless
  // the -fkeep-inline-functions flag has been used. Warning is emitted;
  if (FD && FD->isInlineSpecified()) {
    // FIXME: ... unless the -fkeep-inline-functions flag has been used.
    S.Diag(Attr.getLoc(), diag::warn_attribute_ignored) << "dllexport";
    return;
  }

  unsigned Index = Attr.getAttributeSpellingListIndex();
  DLLExportAttr *NewAttr = S.mergeDLLExportAttr(D, Attr.getRange(), Index);
  if (NewAttr)
    D->addAttr(NewAttr);
}
static void HandleX86ForceAlignArgPointerAttr(Decl *D,
                                              const AttributeList& Attr,
                                              Sema &S) {
  // Check the attribute arguments.
  if (Attr.getNumArgs() != 0) {
    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
    return;
  }

  // If we try to apply it to a function pointer, don't warn, but don't
  // do anything, either. It doesn't matter anyway, because there's nothing
  // special about calling a force_align_arg_pointer function.
  ValueDecl *VD = dyn_cast<ValueDecl>(D);
  if (VD && VD->getType()->isFunctionPointerType())
    return;
  // Also don't warn on function pointer typedefs.
  TypedefNameDecl *TD = dyn_cast<TypedefNameDecl>(D);
  if (TD && (TD->getUnderlyingType()->isFunctionPointerType() ||
             TD->getUnderlyingType()->isFunctionType()))
    return;
  // Attribute can only be applied to function types.
  if (!isa<FunctionDecl>(D)) {
    S.Diag(Attr.getLoc(), diag::warn_attribute_wrong_decl_type)
      << Attr.getName() << /* function */0;
    return;
  }

  D->addAttr(::new (S.Context) X86ForceAlignArgPointerAttr(Attr.getRange(),
                                                           S.Context));
}
static void HandleDLLExportAttr(Decl *D, const AttributeList &Attr, Sema &S) {
  // Currently, the dllexport attribute is ignored for inlined functions, unless
  // the -fkeep-inline-functions flag has been used. Warning is emitted;
  if (isa<FunctionDecl>(D) && cast<FunctionDecl>(D)->isInlineSpecified()) {
    // FIXME: ... unless the -fkeep-inline-functions flag has been used.
    S.Diag(Attr.getLoc(), diag::warn_attribute_ignored) << Attr.getName();
    return;
  }

  unsigned Index = Attr.getAttributeSpellingListIndex();
  DLLExportAttr *NewAttr = S.mergeDLLExportAttr(D, Attr.getRange(), Index);
  if (NewAttr)
    D->addAttr(NewAttr);
}
static void HandleMips16Attr(Decl *D, const AttributeList &Attr, Sema &S) {
  // check the attribute arguments.
  if (Attr.hasParameterOrArguments()) {
    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_number_arguments) << 0;
    return;
  }
  // Attribute can only be applied to function types.
  if (!isa<FunctionDecl>(D)) {
    S.Diag(Attr.getLoc(), diag::err_attribute_wrong_decl_type)
      << Attr.getName() << /* function */0;
    return;
  }
  D->addAttr(::new (S.Context) Mips16Attr(Attr.getRange(), S.Context,
                                          Attr.getAttributeSpellingListIndex()));
}