Index: src/test_hexio.c
==================================================================
--- src/test_hexio.c
+++ src/test_hexio.c
@@ -350,11 +350,11 @@
     Tcl_WrongNumArgs(interp, 1, objv, "BLOB VARNAME");
     return TCL_ERROR;
   }
   zBlob = Tcl_GetByteArrayFromObj(objv[1], &nBlob);
 
-  nVal = getFts3Varint(zBlob, (sqlite3_uint64 *)(&iVal));
+  nVal = getFts3Varint((char*)zBlob, (sqlite3_int64 *)(&iVal));
   Tcl_ObjSetVar2(interp, objv[2], 0, Tcl_NewWideIntObj(iVal), 0);
   Tcl_SetObjResult(interp, Tcl_NewIntObj(nVal));
   return TCL_OK;
 }