Index: lib/AST/ExprConstant.cpp
===================================================================
--- lib/AST/ExprConstant.cpp
+++ lib/AST/ExprConstant.cpp
@@ -433,7 +433,7 @@
   /// rules.  For example, the RHS of (0 && foo()) is not evaluated.  We can
   /// evaluate the expression regardless of what the RHS is, but C only allows
   /// certain things in certain situations.
-  struct LLVM_ALIGNAS(/*alignof(uint64_t)*/ 8) EvalInfo {
+  struct EvalInfo {
     ASTContext &Ctx;
 
     /// EvalStatus - Contains information about the evaluation.
@@ -471,7 +471,7 @@
 
     /// The current array initialization index, if we're performing array
     /// initialization.
-    uint64_t ArrayInitIndex = -1;
+    uint32_t ArrayInitIndex = -1;
 
     /// HasActiveDiagnostic - Was the previous diagnostic stored? If so, further
     /// notes attached to it will also be stored, otherwise they will not be.
@@ -810,7 +810,7 @@
 
     class ArrayInitLoopIndex {
       EvalInfo &Info;
-      uint64_t OuterIndex;
+      uint32_t OuterIndex;
 
     public:
       ArrayInitLoopIndex(EvalInfo &Info)
@@ -819,7 +819,7 @@
       }
       ~ArrayInitLoopIndex() { Info.ArrayInitIndex = OuterIndex; }
 
-      operator uint64_t&() { return Info.ArrayInitIndex; }
+      operator uint32_t&() { return Info.ArrayInitIndex; }
     };
   };
 
@@ -6299,7 +6299,7 @@
 
   auto *CAT = cast<ConstantArrayType>(E->getType()->castAsArrayTypeUnsafe());
 
-  uint64_t Elements = CAT->getSize().getZExtValue();
+  uint32_t Elements = CAT->getSize().getZExtValue();
   Result = APValue(APValue::UninitArray(), Elements, Elements);
 
   LValue Subobject = This;
@@ -6477,7 +6477,7 @@
   }
 
   bool VisitArrayInitIndexExpr(const ArrayInitIndexExpr *E) {
-    if (Info.ArrayInitIndex == uint64_t(-1)) {
+    if (Info.ArrayInitIndex == uint32_t(-1)) {
       // We were asked to evaluate this subexpression independent of the
       // enclosing ArrayInitLoopExpr. We can't do that.
       Info.FFDiag(E);