And the correct version (with the correct cast) ...

This commit was SVN r11330.

opal/event/buffer.c

@@ -62,7 +62,7 @@ evbuffer_new(void)
 {
 	struct evbuffer *buffer;
 	
-	buffer = (evbuffer*)calloc(1, sizeof(struct evbuffer));
+	buffer = (struct evbuffer*)calloc(1, sizeof(struct evbuffer));
 
 	return (buffer);
 }

opal/event/event-internal.h

@@ -31,7 +31,7 @@
 extern "C" {
 #endif
 
-RB_HEAD(opal_event_tree, opal_event);
+typedef RB_HEAD(opal_event_tree, opal_event) opal_event_tree;
 
 struct event_base {
 	const struct opal_eventop *evsel;

opal/event/event.c

@@ -416,7 +416,7 @@ opal_event_base_priority_init(struct event_base *base, int npriorities)
 		event_err(1, "%s: calloc", __func__);
 
 	for (i = 0; i < base->nactivequeues; ++i) {
-		base->activequeues[i] = (opal_event_list*)malloc(sizeof(struct opal_event_list));
+		base->activequeues[i] = (struct opal_event_list*)malloc(sizeof(struct opal_event_list));
 		if (base->activequeues[i] == NULL)
 			event_err(1, "%s: malloc", __func__);
 		TAILQ_INIT(base->activequeues[i]);