From: Junio C Hamano <gitster@pobox.com>
Date: Wed, 28 Oct 2009 07:48:08 GMT
Subject: Re: [PATCH] imap-send.c: fix pointer to be const
Message-ID: <7v8wewq7rb.fsf@alter.siamese.dyndns.org>
In-Reply-To: <7vljiwq8tc.fsf@alter.siamese.dyndns.org>

Junio C Hamano <gitster@pobox.com> writes:

> Vietor Liu <vietor@vxwo.org> writes:
>
>> Fixes some compiler warnings:
>> imap-send.c: In function ‘ssl_socket_connect’:
>> warning: assignment discards qualifiers from pointer target type
>>
>> ====================================================
>> OpenSSL Changes between 0.9.8k and 1.0:
>>
>> *) Let the TLSv1_method() etc. functions return a 'const' SSL_METHOD
>>      pointer and make the SSL_METHOD parameter in SSL_CTX_new,
>>      SSL_CTX_set_ssl_version and SSL_set_ssl_method 'const'.
>>
>> Signed-off-by: Vietor Liu <vietor@vxwo.org>
>
> This is much easier to understand.

This indeed _is_ easier to understand, but what this means is that making
"meth" const will break the compilation for people with 0.9.8k.

Their SSL_CTX_new() does not promise the callers that it won't modify the
object its parameter points at, so SSL_CTX_new(meth) will now see exactly
the same issue.  You will be discarding "const" qualifier by passing it.