diff --git a/tools/perf/builtin-report.c b/tools/perf/builtin-report.c
index 381918515a5c..1fb13e5fd1f9 100644
--- a/tools/perf/builtin-report.c
+++ b/tools/perf/builtin-report.c
@@ -110,8 +110,8 @@ static int perf_session__add_hist_entry(struct perf_session *self,
 
 	if (symbol_conf.use_callchain) {
 		if (!hit)
-			callchain_init(&he->callchain);
-		err = append_chain(&he->callchain, data->callchain, syms);
+			callchain_init(he->callchain);
+		err = append_chain(he->callchain, data->callchain, syms);
 		free(syms);
 
 		if (err)
diff --git a/tools/perf/util/hist.c b/tools/perf/util/hist.c
index f0794913d575..18cf8b321608 100644
--- a/tools/perf/util/hist.c
+++ b/tools/perf/util/hist.c
@@ -50,7 +50,8 @@ struct hist_entry *__perf_session__add_hist_entry(struct rb_root *hists,
 			p = &(*p)->rb_right;
 	}
 
-	he = malloc(sizeof(*he));
+	he = malloc(sizeof(*he) + (symbol_conf.use_callchain ?
+				    sizeof(struct callchain_node) : 0));
 	if (!he)
 		return NULL;
 	*he = entry;
@@ -168,7 +169,7 @@ static void perf_session__insert_output_hist_entry(struct rb_root *root,
 	struct hist_entry *iter;
 
 	if (symbol_conf.use_callchain)
-		callchain_param.sort(&he->sorted_chain, &he->callchain,
+		callchain_param.sort(&he->sorted_chain, he->callchain,
 				      min_callchain_hits, &callchain_param);
 
 	while (*p != NULL) {
diff --git a/tools/perf/util/sort.h b/tools/perf/util/sort.h
index 439ec5fa0f5f..5bf2b744e7b2 100644
--- a/tools/perf/util/sort.h
+++ b/tools/perf/util/sort.h
@@ -49,12 +49,12 @@ struct hist_entry {
 	u64			ip;
 	char			level;
 	struct symbol	  *parent;
-	struct callchain_node	callchain;
 	union {
 		unsigned long	  position;
 		struct hist_entry *pair;
 		struct rb_root	  sorted_chain;
 	};
+	struct callchain_node	callchain[0];
 };
 
 enum sort_type {