this is the output of `-Wl,--print-memory-usage`:
```
Memory region         Used Size  Region Size  %age Used
             rom:      130012 B       128 KB     99.19%
             ram:        3596 B        20 KB     17.56%
```
and this is size:
```
  text	   data	    bss	    dec	    hex	filename
 121416	    404	   3188	 125008	  1e850	src/blackmagic.elf
```
quite a significant difference if I want to know how much space I have left