Null pointer dereference in array_copy

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The following input demonstrates a crash:

Range = Struct
Array(0..0)

ASAN report:

==73305==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000000 (pc 0x7fffbbdccf3d bp 0x7fff57b61490 sp 0x7fff57b61490 T0)
==73305==The signal is caused by a READ memory access.
==73305==Hint: address points to the zero page.
    #0 0x7fffbbdccf3c in _platform_memmove$VARIANT$Haswell (libsystem_platform.dylib:x86_64+0x5f3c)
    #1 0x10849b504 in __asan_memcpy (libclang_rt.asan_osx_dynamic.dylib:x86_64h+0x4d504)
    #2 0x10809767c in array_copy array.c:71
    #3 0x10809745f in mrb_ary_new_from_values array.c:80
    #4 0x10825eac5 in mrb_struct_to_a struct.c:624
    #5 0x1081ee145 in mrb_funcall_with_block vm.c:444
    #6 0x1081eaf17 in mrb_funcall_argv vm.c:461
    #7 0x10817024e in convert_type object.c:320
    #8 0x10817136a in mrb_check_convert_type object.c:356
    #9 0x1082a2aa3 in mrb_f_array (mruby:x86_64+0x10020faa3)
    #10 0x108202d88 in mrb_vm_exec vm.c:1268
    #11 0x1081f7f39 in mrb_vm_run vm.c:824
    #12 0x10822a849 in mrb_top_run vm.c:2630
    #13 0x1082fb845 in mrb_load_exec parse.y:5762
    #14 0x1082fc655 in mrb_load_file_cxt parse.y:5771
    #15 0x108094e66 in main mruby.c:227
    #16 0x7fffbbbba234 in start (libdyld.dylib:x86_64+0x5234)

==73305==Register values:
rax = 0x000000010ba21800  rbx = 0x00000001092154c0  rcx = 0x0000000000000000  rdx = 0x0000000000000008
rdi = 0x000000010ba21800  rsi = 0x0000000000000000  rbp = 0x00007fff57b61490  rsp = 0x00007fff57b61490
 r8 = 0x0000100000000000   r9 = 0x0000000000000000  r10 = 0x0000000000001052  r11 = 0x000000010ba21800
r12 = 0x00001fffeaf6c528  r13 = 0x0000000000000000  r14 = 0x0000000000000010  r15 = 0x000000010ba21800
AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV (libsystem_platform.dylib:x86_64+0x5f3c) in _platform_memmove$VARIANT$Haswell
==73305==ABORTING
Abort trap: 6

This issue was reported by https://hackerone.com/ilsani