Description of problem:

$ guestfish --ro -a /tmp/f18x64.vhdx -i

Segfaults with the following stack trace:

libguestfs: error: internal_parse_mountable: internal_parse_mountable_stub: /dev/fedora/root: No such file or directory

Program received signal SIGSEGV, Segmentation fault.
guestfs___check_for_filesystem_on (g=g@entry=0x55555584c620, 
    mountable=0x555555862bb0 "/dev/fedora/root") at inspect-fs.c:122
122	  if (m->im_type == MOUNTABLE_DEVICE) {
Missing separate debuginfos, use: debuginfo-install cyrus-sasl-lib-2.1.25-2.fc18.x86_64 gnome-keyring-3.6.3-1.fc18.x86_64 libconfig-1.4.8-3.fc18.x86_64 libselinux-2.1.12-7.3.fc18.x86_64
(gdb) bt
#0  guestfs___check_for_filesystem_on (g=g@entry=0x55555584c620, 
    mountable=0x555555862bb0 "/dev/fedora/root") at inspect-fs.c:122
#1  0x00007ffff72e3a20 in guestfs__inspect_os (g=g@entry=0x55555584c620)
    at inspect.c:58
#2  0x00007ffff7268ba5 in guestfs_inspect_os (g=0x55555584c620)
    at actions-0.c:499
#3  0x00005555555abebb in inspect_mount () at inspect.c:66
#4  0x000055555557b3ae in main (argc=<optimized out>, argv=0x7fffffffde88)
    at fish.c:471
(gdb) frame 0
#0  guestfs___check_for_filesystem_on (g=g@entry=0x55555584c620, 
    mountable=0x555555862bb0 "/dev/fedora/root") at inspect-fs.c:122
122	  if (m->im_type == MOUNTABLE_DEVICE) {
(gdb) print m
$1 = (struct guestfs_internal_mountable *) 0x0


Version-Release number of selected component (if applicable):

guestfish 1.21.37fedora=20,release=1.fc20,libvirt

How reproducible:

100%

Steps to Reproduce:
1. See above.