diff --git a/src/cryptoconditions/src/json_rpc.c b/src/cryptoconditions/src/json_rpc.c
index 42c13612c..13cffec1d 100644
--- a/src/cryptoconditions/src/json_rpc.c
+++ b/src/cryptoconditions/src/json_rpc.c
@@ -1,8 +1,12 @@
 #include "cryptoconditions.h"
 #include "internal.h"
 #include <cJSON.h>
-#include <malloc.h>
 
+#ifdef __LP64__
+#include <stdlib.h>
+#else
+#include <malloc.h>            // Index into CTransaction.vjoinsplit
+#endif
 
 static cJSON *jsonCondition(CC *cond) {
     cJSON *root = cJSON_CreateObject();