Re: LinuxAsmTools Announcement

["pei lin" <telent998@xxxxxxxxx>]

OH~~~ great,thx for u help,that really a tip.

2008/12/19 Brian Raiter <breadbox@xxxxxxxxxxxxxx>:
>> when i disassemble *.o object file on x86 machine and find
>> instruction "call 0xFCFFFFFF",because not link,but why this address
>> 0xFCFFFFFF not 0xFFFFFFFF or others?
>
> First of all, the value is not 0xFCFFFFFF, it's 0xFFFFFFFC
> (little-endian), which is the 32-bit equivalent of -4.
>
> And the reason for the -4 is that it's an offset. When the linker
> fills in the real address, it will subtract the subroutine's absolute
> address from the address of the -4 value to get a relative address,
> which it will then add to the existing -4 to get the correct relative
> address for the call instruction. And, the reason that 4 needs to be
> subtracted is that when the call is executed, it will actually jump
> from the end of the call instruction, which is 4 bytes ahead of where
> the relative address is stored.
>
> b
>
>
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