Index: lib/Sema/SemaChecking.cpp
===================================================================
--- lib/Sema/SemaChecking.cpp
+++ lib/Sema/SemaChecking.cpp
@@ -6023,7 +6023,7 @@
   return IntRange(MaxWidth, Ty->isUnsignedIntegerOrEnumerationType());
 }
 
-static QualType GetExprType(Expr *E) {
+static QualType GetExprType(const Expr *E) {
   QualType Ty = E->getType();
   if (const AtomicType *AtomicRHS = Ty->getAs<AtomicType>())
     Ty = AtomicRHS->getValueType();
@@ -6034,7 +6034,7 @@
 /// range of values it might take.
 ///
 /// \param MaxWidth - the width to which the value will be truncated
-static IntRange GetExprRange(ASTContext &C, Expr *E, unsigned MaxWidth) {
+static IntRange GetExprRange(ASTContext &C, const Expr *E, unsigned MaxWidth) {
   E = E->IgnoreParens();
 
   // Try a full evaluation first.
@@ -6045,7 +6045,7 @@
   // I think we only want to look through implicit casts here; if the
   // user has an explicit widening cast, we should treat the value as
   // being of the new, wider type.
-  if (ImplicitCastExpr *CE = dyn_cast<ImplicitCastExpr>(E)) {
+  if (const ImplicitCastExpr *CE = dyn_cast<ImplicitCastExpr>(E)) {
     if (CE->getCastKind() == CK_NoOp || CE->getCastKind() == CK_LValueToRValue)
       return GetExprRange(C, CE->getSubExpr(), MaxWidth);
 
@@ -6071,7 +6071,7 @@
                     SubRange.NonNegative || OutputTypeRange.NonNegative);
   }
 
-  if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
+  if (const ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
     // If we can fold the condition, just take that operand.
     bool CondResult;
     if (CO->getCond()->EvaluateAsBooleanCondition(CondResult, C))
@@ -6085,7 +6085,7 @@
     return IntRange::join(L, R);
   }
 
-  if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
+  if (const BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
     switch (BO->getOpcode()) {
 
     // Boolean-valued operations are single-bit and positive.
@@ -6225,7 +6225,7 @@
     return IntRange::join(L, R);
   }
 
-  if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
+  if (const UnaryOperator *UO = dyn_cast<UnaryOperator>(E)) {
     switch (UO->getOpcode()) {
     // Boolean-valued operations are white-listed.
     case UO_LNot:
@@ -6241,17 +6241,17 @@
     }
   }
 
-  if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E))
+  if (const OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E))
     return GetExprRange(C, OVE->getSourceExpr(), MaxWidth);
 
-  if (FieldDecl *BitField = E->getSourceBitField())
+  if (const FieldDecl *BitField = E->getSourceBitField())
     return IntRange(BitField->getBitWidthValue(C),
                     BitField->getType()->isUnsignedIntegerOrEnumerationType());
 
   return IntRange::forValueOfType(C, GetExprType(E));
 }
 
-static IntRange GetExprRange(ASTContext &C, Expr *E) {
+static IntRange GetExprRange(ASTContext &C, const Expr *E) {
   return GetExprRange(C, E, C.getIntWidth(GetExprType(E)));
 }