is_erased can take the value 0 (no), 1 (yes), or -1 (unknown). Checks like (!is_erased) don't do the right thing if it's -1. Change-Id: I10ba32c99494ca803e0a7a1ba56fdd78184b96bb Signed-off-by: Jim Paris <jim@jtan.com> Reviewed-on: http://openocd.zylin.com/2366 Tested-by: jenkins Reviewed-by: Spencer Oliver <spen@spen-soft.co.uk>