Freeing unallocated pointer when "dd" command is pressed twice on the same line

```
 1 viw(67069,0x7fff9cdb93c0) malloc: *** error for object 0x7fc9bb4075c0: pointer being freed was not allocated
~                              *** set a breakpoint in malloc_error_break to debug
~ [1]    67069 abort      ./viw s
```