get_error_lines:
        mov     eax,[ebx]
   cmp     byte [eax],0
        je      get_next_error_line
 test    byte [ebx+7],80h   ;<===
 jz      error_lines_ok
      inc     ecx
 mov     edx,ebx
      find_definition_origin:
        mov     edx,[edx+12]
        test    byte [edx+7],80h   ;<===
 jnz     find_definition_origin
      mov     eax,[edx+4]
 and     eax,7FFFFFFFh   ;<--- A) useless
     push    eax
 mov     edx,[edx]
   push    edx
      get_next_error_line:
       mov     ebx,[ebx+8]
 jmp     get_error_lines
      error_lines_ok:
        inc     ecx
 mov     eax,[ebx+4]
 and     eax,7FFFFFFFh   ;<--- B) useless
     push    eax
 mov     edx,[ebx]
   push    edx
 mov     ebx,ecx
     inc     ecx
 shl     ecx,3

    

I think more important would be to give names to all the magic constants.

Or even more: add some comments revealing what register holds what