sb = &tc->sack_sb;
/* Check if snd_una is a lost retransmit */
- if (seq_gt (sb->high_sacked, tc->snd_congestion)
+ if (pool_elts (sb->holes)
+ && seq_gt (sb->high_sacked, tc->snd_congestion)
&& tc->rxt_head != tc->snd_una
&& tcp_retransmit_should_retry_head (tc, sb))
{