Re: [PATCH 1/4] fs/ext3/balloc.c: delete useless initialization

[Eric Sandeen <sandeen@redhat.com>]

On 8/4/11 5:40 AM, Jan Kara wrote:
> On Thu 04-08-11 12:29:31, Julia Lawall wrote:
>> From: Julia Lawall <julia@diku.dk>
>>
>> Delete nontrivial initialization that is immediately overwritten by the
>> result of an allocation function.
>   Thanks. Merged.

Just FWIW, I was curious how this ended up here.

It looks like this has been there since 2005, and both
lines went in in the same commit (i.e. it didn't creep in over time).

http://git.kernel.org/?p=linux/kernel/git/torvalds/old-2.6-bkcvs.git;a=commitdiff;h=a66d457d8878fe8d09bc81f0d5e6ac40caec6eb7

-Eric

> 								Honza
> 
>>
>> The semantic match that makes this change is as follows:
>> (http://coccinelle.lip6.fr/)
>>
>> // <smpl>
>> @@
>> type T;
>> identifier i;
>> expression e;
>> @@
>>
>> (
>> T i = \(0\|NULL\|ERR_PTR(...)\);
>> |
>> -T i = e;
>> +T i;
>> )
>> ... when != i
>> i = \(kzalloc\|kcalloc\|kmalloc\)(...);
>>
>> // </smpl>
>>
>> Signed-off-by: Julia Lawall <julia@diku.dk>
>>
>> ---
>>  fs/ext3/balloc.c |    2 +-
>>  1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff -u -p a/fs/ext3/balloc.c b/fs/ext3/balloc.c
>> --- a/fs/ext3/balloc.c
>> +++ b/fs/ext3/balloc.c
>> @@ -427,7 +427,7 @@ static inline int rsv_is_empty(struct ex
>>  void ext3_init_block_alloc_info(struct inode *inode)
>>  {
>>  	struct ext3_inode_info *ei = EXT3_I(inode);
>> -	struct ext3_block_alloc_info *block_i = ei->i_block_alloc_info;
>> +	struct ext3_block_alloc_info *block_i;
>>  	struct super_block *sb = inode->i_sb;
>>  
>>  	block_i = kmalloc(sizeof(*block_i), GFP_NOFS);
>>