little bug after called func free

[EugeneBogush]

eee@uuu:/opt/ss7/libtcap/tests$ ./encode
ret: 30
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*** Error in `./encode': free(): invalid pointer: 0x00007ffeb548f5a0 ***

gdb:
#0 0x00007fc233800428 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54
#1 0x00007fc23380202a in __GI_abort () at abort.c:89
#2 0x00007fc2338427ea in __libc_message (do_abort=do_abort@entry=2, fmt=fmt@entry=0x7fc23395be98 "*** Error in `%s': %s: 0x%s ***\n")
at ../sysdeps/posix/libc_fatal.c:175
#3 0x00007fc23384b37a in malloc_printerr (ar_ptr=, ptr=, str=0x7fc233958c6f "free(): invalid pointer",
action=3) at malloc.c:5006
#4 _int_free (av=, p=, have_lock=0) at malloc.c:3867
#5 0x00007fc23384f53c in __GI___libc_free (mem=) at malloc.c:2968
#6 0x0000000000400c48 in main () at encode.c:58
(gdb) Quit