[Bug 19859] New: cygwin's rsync -aq --delete-before crashes; breaks cygwin bash build

http://bugs.winehq.org/show_bug.cgi?id=19859

Summary: cygwin's rsync -aq --delete-before crashes; breaks
                    cygwin bash build
           Product: Wine
           Version: 1.1.23
          Platform: PC
               URL: http://cygwin.com
        OS/Version: Linux
            Status: NEW
          Keywords: download, source
          Severity: normal
          Priority: P2
         Component: -unknown
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]

[This is the next problem after bug 19858.)
To debug bug 19856, I decided to try to build cygwin's bash
from source so I could see why it refuses to run some commands.
Hilarity ensued.

To repeat:
1) run 
$ winetricks cygwin
and select gcc, automake, patch, and cygport

2) start a cygwin shell
$ cd ~/.wine/drive_c/cygwin
$ wine wineconsole cmd /c cygwin.bat
then use that for all further commands

3) read 'man cygport'

4) download the bash source package from your favorite cygwin mirror, e.g.
$ wget http://cygwin.osuosl.org/release/bash/bash-3.2.49-22-src.tar.bz2

To work around bug 19858, edit cygwin's /bin/cygport and change the two lines
 warn "${unpack_cmd} ${unpack_file_name} failed"
to say
 echo "${unpack_cmd} ${unpack_file_name} failed"

5) unpack the source tarball and use cygport to prepare and build it
$ mkdir temp
$ cd temp
$ tar -xjvf ../bash-3.2.49-22-src.tar.bz2
$ cygport prep bash*cygport

This takes a couple minutes, and fails at the very end with
> > > Preparing working source directory

+ rsync -aq --delete-before /cygdrive/c/bb/bash-3.2.49-22/origsrc/
/cygdrive/c/bb/bash-3.2.49-22/src/
/usr/bin/cygport: line 779:    67 Segmentation fault      (core dumped) rsync
-aq --delete-before ${origsrcdir}/ ${srcdir}/

You can reproduce this almost on its own by running that rsync
inside wineconsole yourself.  (Doing it noninteractively
doesn't seem to crash :-( )
Leaving off the --delete-before avoids the crash.

Workaround: edit cygwin's /bin/cygport to use cp -a instead of rsync, e.g.
change
        rsync -aq --delete-before ${origsrcdir}/ ${srcdir}/;
to
        rm -rf ${srcdir}/
        cp -a ${origsrcdir}/ ${srcdir}/;