Segmentation fault when read exceeds reference boundaries

[karel-brinda]

Program received signal SIGSEGV, Segmentation fault.
ococo::caller_t<unsigned short, 3, 4>::run (this=this@entry=0x7fffffffdb00)
    at caller.h:287
287                         stats->seq_stats[seqid][ref_pos] = stats->increment(
(gdb) where
#0  ococo::caller_t<unsigned short, 3, 4>::run (this=this@entry=0x7fffffffdb00)
    at caller.h:287
#1  0x0000000000404112 in main (argc=<optimized out>, argv=<optimized out>)
    at main.cpp:22