From: Junio C Hamano <gitster@pobox.com>
Date: Wed, 31 Aug 2011 17:03:36 GMT
Subject: Re: [PATCH] xdiff/xprepare: initialise xdlclassifier_t cf in xdl_prepare_env()
Message-ID: <7vaaapzf6f.fsf@alter.siamese.dyndns.org>
In-Reply-To: <7vei01zf89.fsf@alter.siamese.dyndns.org>

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

> Tay Ray Chuan <rctay89@gmail.com> writes:
>
>> Ensure that the xdl_free_classifier() call on xdlclassifier_t cf is safe
>> even if xdl_init_classifier() isn't called. This may occur in the case
>> where diff is run with --histogram and a call to, say, xdl_prepare_ctx()
>> fails.
>>
>> Signed-off-by: Tay Ray Chuan <rctay89@gmail.com>
>
> Thanks. Did you find this by code inspection?
>
>>  xdiff/xprepare.c |    3 +++
>>  1 files changed, 3 insertions(+), 0 deletions(-)
>>
>> diff --git a/xdiff/xprepare.c b/xdiff/xprepare.c
>> index 620fc9a..4323596 100644
>> --- a/xdiff/xprepare.c
>> +++ b/xdiff/xprepare.c
>> @@ -239,6 +239,9 @@ int xdl_prepare_env(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp,
>>  	long enl1, enl2, sample;
>>  	xdlclassifier_t cf;
>>  
>> +	cf.rchash = NULL;
>> +	cf.ncha.head = NULL;
>
> Would it be more appropriate to use memcpy(&cf, 0, sizeof(cf)) instead, so

Oops, I meant memset(), obviously.

> that we wouldn't have to worry about a similar breakage when a new field
> is added to "struct xdlclassifier" later?