Jeff King <p...@peff.net> writes:

> I happened to notice today that this topic needs a minor tweak:
>
> -- >8 --
> Subject: [PATCH] add_delta_base_cache: use list_for_each_safe
>
> We may remove elements from the list while we are iterating,
> which requires using a second temporary pointer. Otherwise
> stepping to the next element of the list might involve
> looking at freed memory (which generally works in practice,
> as we _just_ freed it, but of course is wrong to rely on;
> valgrind notices it).

I failed to notice it, too.  Thanks.

> Signed-off-by: Jeff King <p...@peff.net>
> ---
>  sha1_file.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/sha1_file.c b/sha1_file.c
> index a57b71d..132c861 100644
> --- a/sha1_file.c
> +++ b/sha1_file.c
> @@ -2187,11 +2187,11 @@ static void add_delta_base_cache(struct packed_git 
> *p, off_t base_offset,
>       void *base, unsigned long base_size, enum object_type type)
>  {
>       struct delta_base_cache_entry *ent = xmalloc(sizeof(*ent));
> -     struct list_head *lru;
> +     struct list_head *lru, *tmp;
>  
>       delta_base_cached += base_size;
>  
> -     list_for_each(lru, &delta_base_cache_lru) {
> +     list_for_each_safe(lru, tmp, &delta_base_cache_lru) {
>               struct delta_base_cache_entry *f =
>                       list_entry(lru, struct delta_base_cache_entry, lru);
>               if (delta_base_cached <= delta_base_cache_limit)

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