Shotwell crashes on save of _modified file by GIMP

[Monster Danau]

1) Choose: Edit in external editor (append _modified)
2) Edit with GIMP
3) Save (overwrite file_modified.JPG)
4) Shotwell crashes:

L 8995 2014-04-07 11:05:19 [CRT] Photo.vala:1285: Photo update: [259] /path/to/2356.JPG (/path/to/2356_modified.JPG) no longer a recognized image
Segmentation fault (core dumped)

Ubuntu: 12.04 x86_64
Processor: AMD C-60 APU with Radeon(tm) HD Graphics × 2
Ram: 4GB

Shotwell: 0.14.1 (and previous)
GIMP: 2.8.10 (and previous)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Chad Miller (cmiller)]

Program received signal SIGSEGV, Segmentation fault.
0x00000000005e4d2d in photo_update_editable (self=self@entry=0x6cc9f00,
    only_attributes=only_attributes@entry=0, new_reader=new_reader@entry=0x0,
    error=error@entry=0x7fffb76913a8) at src/Photo.c:18238

(gdb) bt 4 full

#0 0x00000000005e4d2d in photo_update_editable (self=self@entry=0x6cc9f00, only_attributes=only_attributes@entry=0, new_reader=new_reader@entry=0x0, error=error@entry=0x7fffb76913a8) at src/Photo.c:18238
        _tmp79_ = 0x0
        _tmp80_ = {id = 24}
        _tmp82_ = 0x0
        _tmp81_ = 0x0
        _tmp83_ = 0x0
        _tmp75_ = 1
        _tmp76_ = <optimized out>
        _tmp78_ = 1
        _tmp1_ = <optimized out>
        _tmp2_ = 0
        _tmp4_ = <optimized out>
        old_reader = 0x3fb6e70
        _tmp7_ = 0x3fb6e70
        _tmp8_ = 0x3fb6e70
        _tmp9_ = <optimized out>
        _tmp10_ = <optimized out>
        _tmp11_ = <optimized out>
        reader = 0x3fb6e70
        _tmp14_ = 0x3fb6e70
        _tmp15_ = <optimized out>
        _tmp16_ = 0x3fb6e70
        timestamp_changed = 0
        filesize_changed = 0
        is_new_editable = 0
        editable_id = {id = 24}
        _tmp17_ = {id = 24}
        file = 0x1915fa0
        _tmp18_ = 0x3fb6e70
        _tmp19_ = 0x1915fa0
        detected = <optimized out>
        backing = 0x0
        _tmp20_ = 0x1915fa0
        _tmp21_ = 0x0
        _tmp22_ = 0x0
        _tmp23_ = <optimized out>
        _tmp41_ = 0
        _tmp100_ = 0x0
        _tmp106_ = 0
        _tmp107_ = 0
        _tmp110_ = 0
        alteration_list = 0x0
        _tmp121_ = 0x0
        alteration_list_length1 = 0
        _alteration_list_size_ = 0
        _tmp122_ = 0
        _tmp130_ = 0
        _tmp131_ = 0
        _tmp133_ = 0
        _tmp141_ = 0x0
        _tmp141__length1 = 0
        _inner_error_ = 0x0
        __FUNCTION__ = "photo_update_editable"
#1 0x00000000005e7fb1 in photo_reimport_editable (self=self@entry=0x6cc9f00, error=error@entry=0x7fffb76913e8) at src/Photo.c:17805
        _inner_error_ = 0x0
        __FUNCTION__ = "photo_reimport_editable"
#2 0x00000000005e808b in photo_on_reimport_editable (self=0x6cc9f00) at src/Photo.c:18903
        _tmp1_ = 0x0
        _inner_error_ = 0x0
        _tmp0_ = 0x12e99dc0 "Hx9\020\356\177"
#3 _photo_on_reimport_editable_one_shot_callback (self=0x6cc9f00) at src/Photo.c:18758
No locals.

(gdb) f

#0 0x00000000005e4d2d in photo_update_editable (self=self@entry=0x6cc9f00, only_attributes=only_attributes@entry=0, new_reader=new_reader@entry=0x0, error=error@entry=0x7fffb76913a8) at src/Photo.c:18238
18238 in src/Photo.c

(gdb) ptype new_reader
type = struct _PhotoFileReader {
    PhotoFileAdapter parent_instance;
    PhotoFileReaderPrivate *priv;
} *

(gdb) p *new_reader

Cannot access memory at address 0x0

(gdb) ptype error

type = struct _GError {
    GQuark domain;
    gint code;
    gchar *message;
} **

(gdb) p *error

$1 = (GError *) 0x0
(gdb) p *self
$2 = {parent_instance = {parent_instance = {parent_instance = {parent_instance = {parent_instance = {parent_instance = {g_type_instance = {g_class = 0x1c66ea0}, ref_count = 26, qdata = 0x113fa200}, priv = 0x6cc9ee0}, priv = 0x6...