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

[Hui Zhu <teawater@gmail.com>]

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

>
> 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;
>>      }
>>
>