Re: [PATCH] Fixed crash in fetching remote tags when there is not tags.

> Still, I'd suggest move the test into the caller, firstly because it
> is the only place that special. Also, I can't think of a proper reason
> to add a NULL ref to a reflist, and so the crashing tail_link_ref will
> help us find the callers which use tail_link_ref incorrectly
> (illogically too).
> 
> As the result of patter expansion can be NULL (empty pattern, as it
> seems), lets just check for it. I parked the patch below locally.
> 
> diff --git a/remote.c b/remote.c
> index 5e92378..58d63ed 100644
> --- a/remote.c
> +++ b/remote.c
> @@ -884,7 +884,8 @@ int get_fetch_map(struct ref *remote_refs,
>  			    rm->peer_ref->name);
>  	}
>  
> -	tail_link_ref(ref_map, tail);
> +	if (ref_map)
> +		tail_link_ref(ref_map, tail);
>  
>  	return 0;
>  }