(base) [boyi@boyi amgame]$ make

Building amgame-image [x86_64-qemu]

Building am-archive [x86_64-qemu]

• CC src/x86/qemu/ioe.c
  /home/boyi/Code/Systerm/os-workbench-2022/abstract-machine/am/src/x86/qemu/ioe.c: 在函数‘__am_lapic_bootap’中:
  /home/boyi/Code/Systerm/os-workbench-2022/abstract-machine/am/src/x86/qemu/ioe.c:433:6: 错误：array subscript 0 is outside array bounds of ‘uint16_t[0]’ {或称 ‘short unsigned int[]’} [-Werror=array-bounds=]
  433 | wrv[0] = 0;
  | ~~~^~~
  cc1: 附注：source object is likely at address zero
  /home/boyi/Code/Systerm/os-workbench-2022/abstract-machine/am/src/x86/qemu/ioe.c:434:6: 错误：array subscript 0 is outside array bounds of ‘uint16_t[0]’ {或称 ‘short unsigned int[]’} [-Werror=array-bounds=]
  434 | wrv[1] = (uintptr_t)addr >> 4;

Without -fno-strict-aliasing, GCC 12.1.0 generates code to load elf32->e_machine before copy_from_disk(elf32, 4096, 0), causing an x86_64 ELF header to be parsed with load_elf32():

    7d13:	b9 00 fc ff ff       	mov    $0xfffffc00,%ecx
    7d18:	ba 00 04 00 00       	mov    $0x400,%edx
    7d1d:	b8 00 00 01 00       	mov    $0x10000,%eax
[*] 7d22:	66 8b 1d 12 80 00 00 	mov    0x8012,%bx
    7d29:	e8 34 ff ff ff       	call   7c62 <copy_from_disk>
    7d2e:	31 c9                	xor    %ecx,%ecx
    7d30:	ba 00 10 00 00       	mov    $0x1000,%edx
    7d35:	b8 00 80 00 00       	mov    $0x8000,%eax
    7d3a:	e8 23 ff ff ff       	call   7c62 <copy_from_disk>
[*] 7d3f:	66 83 fb 3e          	cmp    $0x3e,%bx

With -fno-strict-aliasing, the compiler gives the following code, and the system correctly boots.

    7d13:	b9 00 fc ff ff       	mov    $0xfffffc00,%ecx
    7d18:	ba 00 04 00 00       	mov    $0x400,%edx
    7d1d:	b8 00 00 01 00       	mov    $0x10000,%eax
    7d22:	e8 3b ff ff ff       	call   7c62 <copy_from_disk>
    7d27:	31 c9                	xor    %ecx,%ecx
    7d29:	ba 00 10 00 00       	mov    $0x1000,%edx
    7d2e:	b8 00 80 00 00       	mov    $0x8000,%eax
    7d33:	e8 2a ff ff ff       	call   7c62 <copy_from_disk>
[*] 7d38:	66 83 3d 12 80 00 00 	cmpw   $0x3e,0x8012

It seems the miscompilation is caused by read_disk's treating its buffer as uint32_t *, and changing that to uint8_t * also solves the problem.

There's a mistake--it should be 7 for ╚ (200).