free(): invalid pointer

Thread 1 "rocksndiamonds" received signal SIGABRT, Aborted.
__GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
50	../sysdeps/unix/sysv/linux/raise.c: No such file or directory.
(gdb) bt
#0  __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:50
#1  0x00007ffff78a1535 in __GI_abort () at abort.c:79
#2  0x00007ffff78f8508 in __libc_message (action=action@entry=do_abort, fmt=fmt@entry=0x7ffff7a0328d "%s\n") at ../sysdeps/posix/libc_fatal.c:181
#3  0x00007ffff78fec1a in malloc_printerr (str=str@entry=0x7ffff7a0143b "free(): invalid pointer") at malloc.c:5341
#4  0x00007ffff790042c in _int_free (av=<optimized out>, p=<optimized out>, have_lock=<optimized out>) at malloc.c:4165
#5  0x0000555555713b28 in checked_free (ptr=0x55555b155960) at misc.c:1275
#6  0x0000555555712b25 in setString (old_value=0x55555860c330 <tape+16>, new_value=0x55555c778b40 "rnd_krystian_abramowicz") at misc.c:844
#7  0x00005555556eca43 in TapeErase () at tape.c:530
#8  0x000055555568771f in GameEnd () at game.c:4775
#9  0x000055555568761d in GameWon () at game.c:4722
#10 0x00005555556a7dbd in GameActionsExt () at game.c:11371
#11 0x00005555556a8485 in GameActions () at game.c:11625
#12 0x000055555567c8b9 in HandleGameActions () at screens.c:8369
#13 0x0000555555646d83 in EventLoop () at events.c:359
#14 0x000055555563a1ca in main (argc=1, argv=0x7fffffffdb18) at main.c:7762
(gdb) # pressed enter at finished level prompt to override old save

Keyboard feels very hot
Fans aren't on
A little after above, CPU monitor said CPU is around 75C
