diff --git a/lib/pure/strutils.nim b/lib/pure/strutils.nim
index 9c205a54f2..9c9da92c61 100644
--- a/lib/pure/strutils.nim
+++ b/lib/pure/strutils.nim
@@ -898,7 +898,7 @@ proc toHex*(x: BiggestInt, len: Positive): string {.noSideEffect,
 
 proc toHex*[T](x: T): string =
   ## Shortcut for ``toHex(x, T.sizeOf * 2)``
-  toHex(x, T.sizeOf * 2)
+  toHex(BiggestInt(x), T.sizeOf * 2)
 
 proc intToStr*(x: int, minchars: Positive = 1): string {.noSideEffect,
   rtl, extern: "nsuIntToStr".} =