diff --git a/clang/include/clang/Basic/LangOptions.def b/clang/include/clang/Basic/LangOptions.def
--- a/clang/include/clang/Basic/LangOptions.def
+++ b/clang/include/clang/Basic/LangOptions.def
@@ -121,7 +121,7 @@
 LANGOPT(WritableStrings   , 1, 0, "writable string support")
 LANGOPT(ConstStrings      , 1, 0, "const-qualified string support")
 ENUM_LANGOPT(LaxVectorConversions, LaxVectorConversionKind, 2,
-             LaxVectorConversionKind::All, "lax vector conversions")
+             All, "lax vector conversions")
 LANGOPT(ConvergentFunctions, 1, 1, "Assume convergent functions")
 LANGOPT(AltiVec           , 1, 0, "AltiVec-style vector initializers")
 LANGOPT(ZVector           , 1, 0, "System z vector extensions")
@@ -293,7 +293,7 @@
 BENIGN_LANGOPT(SemanticInterposition        , 1, 0, "semantic interposition")
 ENUM_LANGOPT(StackProtector, StackProtectorMode, 2, SSPOff,
              "stack protector mode")
-ENUM_LANGOPT(TrivialAutoVarInit, TrivialAutoVarInitKind, 2, TrivialAutoVarInitKind::Uninitialized,
+ENUM_LANGOPT(TrivialAutoVarInit, TrivialAutoVarInitKind, 2, Uninitialized,
              "trivial automatic variable initialization")
 ENUM_LANGOPT(SignedOverflowBehavior, SignedOverflowBehaviorTy, 2, SOB_Undefined,
              "signed integer overflow handling")
@@ -313,7 +313,7 @@
 BENIGN_LANGOPT(NumLargeByValueCopy, 32, 0,
         "if non-zero, warn about parameter or return Warn if parameter/return value is larger in bytes than this setting. 0 is no check.")
 VALUE_LANGOPT(MSCompatibilityVersion, 32, 0, "Microsoft Visual C/C++ Version")
-ENUM_LANGOPT(VtorDispMode, MSVtorDispMode, 2, MSVtorDispMode::ForVBaseOverride,
+ENUM_LANGOPT(VtorDispMode, MSVtorDispMode, 2, ForVBaseOverride,
              "How many vtordisps to insert")
 
 LANGOPT(ApplePragmaPack, 1, 0, "Apple gcc-compatible #pragma pack handling")
@@ -339,7 +339,7 @@
 BENIGN_LANGOPT(AllowEditorPlaceholders, 1, 0,
                "allow editor placeholders in source")
 
-ENUM_LANGOPT(ClangABICompat, ClangABI, 4, ClangABI::Latest,
+ENUM_LANGOPT(ClangABICompat, ClangABI, 4, Latest,
              "version of Clang that we should attempt to be ABI-compatible "
              "with")
 
@@ -353,9 +353,9 @@
 
 COMPATIBLE_VALUE_LANGOPT(MaxTokens, 32, 0, "Max number of tokens per TU or 0")
 
-ENUM_LANGOPT(SignReturnAddressScope, SignReturnAddressScopeKind, 2, SignReturnAddressScopeKind::None,
+ENUM_LANGOPT(SignReturnAddressScope, SignReturnAddressScopeKind, 2, None,
              "Scope of return address signing")
-ENUM_LANGOPT(SignReturnAddressKey, SignReturnAddressKeyKind, 1, SignReturnAddressKeyKind::AKey,
+ENUM_LANGOPT(SignReturnAddressKey, SignReturnAddressKeyKind, 1, AKey,
              "Key used for return address signing")
 LANGOPT(BranchTargetEnforcement, 1, 0, "Branch-target enforcement enabled")
 
diff --git a/clang/lib/Basic/LangOptions.cpp b/clang/lib/Basic/LangOptions.cpp
--- a/clang/lib/Basic/LangOptions.cpp
+++ b/clang/lib/Basic/LangOptions.cpp
@@ -16,7 +16,8 @@
 
 LangOptions::LangOptions() {
 #define LANGOPT(Name, Bits, Default, Description) Name = Default;
-#define ENUM_LANGOPT(Name, Type, Bits, Default, Description) set##Name(Default);
+#define ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
+  set##Name(Type::Default);
 #include "clang/Basic/LangOptions.def"
 }
 
@@ -24,7 +25,7 @@
 #define LANGOPT(Name, Bits, Default, Description)
 #define BENIGN_LANGOPT(Name, Bits, Default, Description) Name = Default;
 #define BENIGN_ENUM_LANGOPT(Name, Type, Bits, Default, Description) \
-  Name = Default;
+  Name = static_cast<unsigned>(Type::Default);
 #include "clang/Basic/LangOptions.def"
 
   // These options do not affect AST generation.