perl stack trace from gdb (also from coredump)

gistfile1.txt

define perl_stack
    set $end=my_perl->Icurstackinfo->si_cxix
    set $i=0
    while ($i<$end)
        printf "%d:%s\n", my_perl->Icurstackinfo->si_cxstack[$i].cx_u.cx_blk.blku_oldcop->cop_line, my_perl->Icurstackinfo->si_cxstack[$i].cx_u.cx_blk.blku_oldcop->cop_file
        set $i=$i+1
    end
    printf "%d:%s\n",my_perl->Icurcop->cop_line, my_perl->Icurcop->cop_file
end

# inspired by https://github.com/ahiguti/gdbperl/blob/master/gdbperl.pl
# https://www.slideshare.net/hirose31/inspect-runningperl
# http://perl.apache.org/docs/2.0/devel/debug/c.html#Analyzing_the_core_File
# https://stackoverflow.com/a/11375936/1555175