diff --git a/dmd/expression.c b/dmd/expression.c
index 4914515c..6569de4c 100644
--- a/dmd/expression.c
+++ b/dmd/expression.c
@@ -7532,8 +7532,8 @@ Expression *SliceExp::semantic(Scope *sc)
 
     if (t->ty == Ttuple)
     {
-        lwr = lwr->optimize(WANTvalue);
-        upr = upr->optimize(WANTvalue);
+        lwr = lwr->optimize(WANTvalue | WANTinterpret);
+        upr = upr->optimize(WANTvalue | WANTinterpret);
         uinteger_t i1 = lwr->toUInteger();
         uinteger_t i2 = upr->toUInteger();
 
diff --git a/dmd/mtype.c b/dmd/mtype.c
index 40f04a71..ca10d19e 100644
--- a/dmd/mtype.c
+++ b/dmd/mtype.c
@@ -5492,11 +5492,11 @@ Type *TypeSlice::semantic(Loc loc, Scope *sc)
     TypeTuple *tt = (TypeTuple *)tbn;
 
     lwr = semanticLength(sc, tbn, lwr);
-    lwr = lwr->optimize(WANTvalue);
+    lwr = lwr->optimize(WANTvalue | WANTinterpret);
     uinteger_t i1 = lwr->toUInteger();
 
     upr = semanticLength(sc, tbn, upr);
-    upr = upr->optimize(WANTvalue);
+    upr = upr->optimize(WANTvalue | WANTinterpret);
     uinteger_t i2 = upr->toUInteger();
 
     if (!(i1 <= i2 && i2 <= tt->arguments->dim))
@@ -5536,11 +5536,11 @@ void TypeSlice::resolve(Loc loc, Scope *sc, Expression **pe, Type **pt, Dsymbol
             sc = sc->push(sym);
 
             lwr = lwr->semantic(sc);
-            lwr = lwr->optimize(WANTvalue);
+            lwr = lwr->optimize(WANTvalue | WANTinterpret);
             uinteger_t i1 = lwr->toUInteger();
 
             upr = upr->semantic(sc);
-            upr = upr->optimize(WANTvalue);
+            upr = upr->optimize(WANTvalue | WANTinterpret);
             uinteger_t i2 = upr->toUInteger();
 
             sc = sc->pop();