Re: [PATCH] Fix cygwin build error with i386-linux-tdep.c

Hui Zhu
2009-08-30T14:37:32Z

On Sun, Aug 30, 2009 at 22:09, Hui Zhu<teawater@gmail.com> wrote:
> On Sun, Aug 30, 2009 at 21:56, Mark Kettenis<mark.kettenis@xs4all.nl> wrote:
>>> From: Hui Zhu <teawater@gmail.com>
>>> Date: Sun, 30 Aug 2009 21:15:22 +0800
>>>
>>> 2009-08-29  Hui Zhu  <teawater@gmail.com>
>>>
>>>       * i386-linux-tdep.c (i386_linux_intx80_sysenter_record): Add
>>>       (unsigned) before tmpu32.
>>
>> Ugh!  Casts like that are ugly.
>>
>> This made me look at the code again and realize that what you're doing
>> in that function is wrong.  You should be using
>> regcache_{raw|cooked}_read_unsigned() instead of regcache_raw_read().
>> Then the whole issue of printing an uint32_t goes away.  When you do
>> change the code like that please use a more meaningful variable name
>> instead of 'tmpu32'.  My suggestion would be 'syscall'.
>
> For the regcache_raw_read_unsigned, I am not agres with it.
>
> void
> regcache_raw_read_unsigned (struct regcache *regcache, int regnum,
>                            ULONGEST *val)
> {
>  gdb_byte *buf;
>  gdb_assert (regcache != NULL);
>  gdb_assert (regnum >= 0 && regnum < regcache->descr->nr_raw_registers);
>  buf = alloca (regcache->descr->sizeof_register[regnum]);
>  regcache_raw_read (regcache, regnum, buf);
>  (*val) = extract_unsigned_integer
>             (buf, regcache->descr->sizeof_register[regnum],
>              gdbarch_byte_order (regcache->descr->gdbarch));
> }
>
> It just add a "extract_unsigned_integer".  For this code, it in
> i386-linux-tdep.c.  We know that I386_EAX_REGNUM is 32 bits.  So we
> don't need extract_unsigned_integer to set anything.
>
> Thanks,
> Hui

Oops, I forget that we have the byte order trouble. Thanks for remind
me. I will fix it.

Thanks,
Hui

>
>>
>> Cheers,
>>
>> Mark
>>
>>> Index: gdb/i386-linux-tdep.c
>>> ===================================================================
>>> --- gdb.orig/i386-linux-tdep.c        2009-08-23 21:17:37.000000000 +0800
>>> +++ gdb/i386-linux-tdep.c     2009-08-30 20:19:53.828125000 +0800
>>> @@ -374,7 +374,7 @@
>>>    if (tmpu32 > 499)
>>>      {
>>>        printf_unfiltered (_("Process record and replay target doesn't "
>>> -                           "support syscall number %u\n"), tmpu32);
>>> +                           "support syscall number %u\n"), (unsigned) tmpu32);
>>>        return -1;
>>>      }
>>>
>>
>