Segmentation fault - mrb_gc_mark

How it was found

# gdb /root/mruby-engine/ext/mruby_engine/mruby/bin/mirb
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Reading symbols from /root/mruby-engine/ext/mruby_engine/mruby/bin/mirb...done.
(gdb) run 3.rb
Starting program: /root/mruby-engine/ext/mruby_engine/mruby/bin/mirb 3.rb
mirb - Embeddable Interactive Ruby Shell

 => [300000, 8]
line 2: syntax error, unexpected tIDENTIFIER, expecting keyword_do or '{' or '('
line 3: syntax error, unexpected tAMPER

Program received signal SIGSEGV, Segmentation fault.
mrb_gc_mark (mrb=0x6cf010, obj=0x305c3030325c3737) at /root/mruby-engine/ext/mruby_engine/mruby/src/gc.c:696
696       if (!is_white(obj)) return;
(gdb) x/1i $rip
=> 0x410f75 <mrb_gc_mark+5>:    movzbl 0x1(%rsi),%eax
(gdb) list *$rip
0x410f75 is in mrb_gc_mark (/root/mruby-engine/ext/mruby_engine/mruby/src/gc.c:696).
691
692     MRB_API void
693     mrb_gc_mark(mrb_state *mrb, struct RBasic *obj)
694     {
695       if (obj == 0) return;
696       if (!is_white(obj)) return;
697       mrb_assert((obj)->tt != MRB_TT_FREE);
698       add_gray_list(mrb, &mrb->gc, obj);
699     }
700
(gdb) bt