Description of problem:
Bug reported on libvirt list, latent until 1.1.2 release turned it into an abort():
https://www.redhat.com/archives/libvir-list/2013-September/msg01143.html

Already patched on master and v1.1.2-maint:
commit fe64499dd14315b2d9d62cdf421bd3c97a46b7ac
Author: Simone Gotti <simone.gotti>
Date:   Thu Sep 19 15:08:29 2013 +0200

    virsh: add missing "async" option in opts_block_commit
    
    After commit 8aecd351266a66efa59b7f7be77bf66693d99ce0 it'll detect
    that a required option is not defined and it will assert and exit with:
    
    virsh.c:1364: vshCommandOpt: Assertion `valid->name' failed.
    
    Problem has been latent since commit ed23b106.
    
    Signed-off-by: Eric Blake <eblake>

Version-Release number of selected component:
libvirt-client-1.1.2-1.fc19

Additional info:
reporter:       libreport-2.1.7
backtrace_rating: 4
cmdline:        virsh -c test:///default blockcommit test a --wait
crash_function: __assert_fail_base
executable:     /usr/bin/virsh
kernel:         3.10.7-200.fc19.x86_64
runlevel:       N 5
type:           CCpp
uid:            14986
var_log_messages: Sep 19 13:53:48 red abrt[4807]: Saved core dump of pid 4804 (/usr/bin/virsh) to /var/tmp/abrt/ccpp-2013-09-19-13:53:47-4804 (11567104 bytes)

Truncated backtrace:
Thread no. 1 (6 frames)
 #2 __assert_fail_base at assert.c:92
 #3 __assert_fail at assert.c:101
 #4 vshCommandOpt at virsh.c:1365
 #5 vshCommandOptBool at virsh.c:1633
 #6 cmdBlockCommit at virsh-domain.c:1583
 #7 vshCommandRun at virsh.c:1722