[PATCH COMMITTED] nss_dns: Remove dead PTR IPv4-to-IPv6 mapping code

[Andreas Schwab]

On Sep 06 2017, Florian Weimer <fweimer@redhat.com> wrote:

> On 09/06/2017 03:32 PM, Andreas Schwab wrote:
>> On Sep 06 2017, fweimer@redhat.com (Florian Weimer) wrote:
>> 
>>> 	Remove dead PTR IPv4-to-IPv6 mapping code from nss_dns.
>>> 	* resolv/nss_dns/dns-host.c (getanswer_r): Remove dead code.
>> 
>> In which way is that dead?
>
>       if (type == T_A && qtype == T_AAAA && map)
> 	have_to_map = 1;
>       else if (__glibc_unlikely (type != qtype))
> 	{
> 	  cp += n;
> 	  continue;			/* XXX - had_error++ ? */
> 	}
>
> So have_to_map being true implies that qtype == T_AAAA.  But this means
> that after the if statement, type == T_A || type == T_AAAA.  In
> particular, type != T_PTR, which is why the have_to_map check is
> superfluous.

But it's inside a loop, and have_to_map is not reset.

Andreas.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
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