DASH is a POSIX-compliant implementation of /bin/sh that aims to be as small as possible. It does this without sacrificing speed where possible. In fact, it is significantly faster than bash (the GNU Bourne-Again SHell) for most tasks. This version of dash has been modified to support $LINENO, so it should suffice to run most configure scripts. More importantly, unlike msys-bash, msys-dash has no dependencies other than the MSYS runtime itself. Therefore, dash can be used (it is, in fact, required) to run the rebaseall tool from the msys-rebase package.