diff --git a/c10/util/typeid.h b/c10/util/typeid.h
index 5bdbdc4271d..635e9aa5fc3 100644
--- a/c10/util/typeid.h
+++ b/c10/util/typeid.h
@@ -309,7 +309,7 @@ class _Uninitialized final {};
 //
 
 // item sizes for TypeMeta::itemsize() fast path
-static constexpr size_t scalarTypeItemSizes[NumScalarTypes] = {
+static constexpr uint8_t scalarTypeItemSizes[NumScalarTypes] = {
 #define SCALAR_TYPE_SIZE(T, name) sizeof(T),
   AT_FORALL_SCALAR_TYPES_WITH_COMPLEX_AND_QINTS(SCALAR_TYPE_SIZE)
 #undef SCALAR_TYPE_SIZE