Re: [PATCH] checkout-index.c: Unconditionally free memory

From: Jeff King <peff@peff.net>
Date: May 1, 2015, 19:50 UTC
Message-ID: <20150501195017.GA3493@peff.net>
In-Reply-To: <1430508507-14016-1-git-send-email-sbeller@google.com>

On Fri, May 01, 2015 at 12:28:27PM -0700, Stefan Beller wrote:

Show 10 quoted lines

> It's safe to free the char pointer `p` unconditionally.
> 
> The pointer is assigned just 2 lines earlier as a return from
> prefix_path, which allocates new memory for its return value.
> 
> Then it is used in checkout_file, which passes the pointer on to
> cache_name_pos and write_tempfile_record, both of which do not store
> the pointer in any permanent record.
> 
> So the condition on when to free the pointer is just "always".

That of course makes me wonder why somebody would write this in the first place. :)

It looks like it comes from be65e7d (Fix users of prefix_path() to free() only when necessary, 2006-05-07), which claims that prefix_path sometimes does not allocate. When did that change? Looks like maybe d089eba (setup: sanitize absolute and funny paths in get_pathspec(), 2008-01-28), but it certainly is the case now.

Probably all of the other sites touched by be65e7d could use the same treatment.

-Peff