Segfault when refreshing image browser

[Beep6581]

Originally reported on Google Code with ID 2668

Steps to reproduce (but unfortunatly doesn't happen always :( ):

Open raw therapee, go to a directory (e.g. /tmp) with no images. Of course no image
will be shown.

Copy via a file manager/shell some images (even one) to that directory ( /tmp/ ). Even
jpg.

Switch to raw therapee, and click again on /tmp/ . Thumbs will be shown.

Sometimes trying to open an image rawtherapee will crash with the following output
in the shell:

(rawtherapee:2244): glibmm-ERROR **: 
unhandled exception (type std::exception) in signal handler:
what: std::bad_alloc

Rilevato trace/breakpoint (core dump creato)

I haven't found the core dump.

This is the apport log:

ERROR: apport (pid 2335) Sat Feb 14 11:18:19 2015: called for pid 2244, signal 5, core
limit 0
ERROR: apport (pid 2335) Sat Feb 14 11:18:19 2015: executable: /home/foto/rt_default_release/rawtherapee
(command line "./rawtherapee")
ERROR: apport (pid 2335) Sat Feb 14 11:18:19 2015: executable does not belong to a
package, ignoring

Dmesg:
kernel: [ 3247.949797] traps: pool[2332] trap int3 ip:7f11781b0c13 sp:7f1133ffe9e0
error:0

Branch: default
Version: 4.2.89
Changeset: c911a987a49c
Compiler: cc 4.8.2
Processor: undefined
System: Linux
Bit depth: 64 bits
Gtkmm: V2.24.4
Build type: release
Build flags:  -Wno-unused-result -Wno-aggressive-loop-optimizations -march=native -fopenmp
-Werror=unknown-pragmas -O3 -DNDEBUG
Link flags:   -march=native
OpenMP support: ON
MMAP support: ON

Reported by fotogiuliopv on 2015-02-14 10:31:00

[Beep6581]

I get similar segfaults in similar situations, and try as I did I never managed to reproduce
them in debug/gdb! Often this involves the "y2 < y1" message in the console, or something
to that effect.

Reported by entertheyoni on 2015-02-14 10:43:40