missing free

Author: petrelharp

c/tskit/trees.c

@@ -3697,6 +3697,9 @@ tsk_treeseq_branch_allele_frequency_spectrum(const tsk_treeseq_t *self,
     if (branch_length != NULL) {
         free(branch_length);
     }
+    if (coordinate != NULL) {
+        free(coordinate);
+    }
     return ret;
 }