diff --git a/clang/include/clang/Basic/Attr.td b/clang/include/clang/Basic/Attr.td
--- a/clang/include/clang/Basic/Attr.td
+++ b/clang/include/clang/Basic/Attr.td
@@ -2255,6 +2255,13 @@
   let Documentation = [OptnoneDocs];
 }
 
+def NeverOptimizeNone : InheritableAttr {
+  // This attribute has no spellings as it is only ever created implicitly.
+  let Spellings = [];
+  let Subjects = SubjectList<[Function]>;
+  let Documentation = [Undocumented];
+}
+
 def Overloadable : Attr {
   let Spellings = [Clang<"overloadable">];
   let Subjects = SubjectList<[Function], ErrorDiag>;
diff --git a/clang/lib/CodeGen/CodeGenModule.cpp b/clang/lib/CodeGen/CodeGenModule.cpp
--- a/clang/lib/CodeGen/CodeGenModule.cpp
+++ b/clang/lib/CodeGen/CodeGenModule.cpp
@@ -1928,7 +1928,8 @@
   ShouldAddOptNone &= !D->hasAttr<AlwaysInlineAttr>();
 
   // Add optnone, but do so only if the function isn't always_inline.
-  if ((ShouldAddOptNone || D->hasAttr<OptimizeNoneAttr>()) &&
+  if (!D->hasAttr<NeverOptimizeNoneAttr>() &&
+      (ShouldAddOptNone || D->hasAttr<OptimizeNoneAttr>()) &&
       !F->hasFnAttribute(llvm::Attribute::AlwaysInline)) {
     B.addAttribute(llvm::Attribute::OptimizeNone);
 
diff --git a/clang/lib/Sema/SemaDeclAttr.cpp b/clang/lib/Sema/SemaDeclAttr.cpp
--- a/clang/lib/Sema/SemaDeclAttr.cpp
+++ b/clang/lib/Sema/SemaDeclAttr.cpp
@@ -8519,6 +8519,9 @@
   case ParsedAttr::AT_OptimizeNone:
     handleOptimizeNoneAttr(S, D, AL);
     break;
+  case ParsedAttr::AT_NeverOptimizeNone:
+    handleSimpleAttribute<NeverOptimizeNoneAttr>(S, D, AL);
+    break;
   case ParsedAttr::AT_EnumExtensibility:
     handleEnumExtensibilityAttr(S, D, AL);
     break;