diff --git a/vpi/libvpi.c b/vpi/libvpi.c
index 100d6f084..cf4c2ee72 100644
--- a/vpi/libvpi.c
+++ b/vpi/libvpi.c
@@ -218,6 +218,11 @@ PLI_INT32 vpi_free_object(vpiHandle ref)
       assert(vpip_routines);
       return vpip_routines->free_object(ref);
 }
+PLI_INT32 vpi_release_handle(vpiHandle ref)
+{
+      assert(vpip_routines);
+      return vpip_routines->release_handle(ref);
+}
 PLI_INT32 vpi_get_vlog_info(p_vpi_vlog_info info)
 {
       assert(vpip_routines);
diff --git a/vpi/sys_sdf.c b/vpi/sys_sdf.c
index 1f2658b45..830837a48 100644
--- a/vpi/sys_sdf.c
+++ b/vpi/sys_sdf.c
@@ -207,6 +207,7 @@ void sdf_interconnect_delays(struct interconnect_port_s port1, struct interconne
 
 	    if (!iter) {
 		  vpi_printf("SDF ERROR: %s:%d: Could not find vpiBit iterator for port1!\n", sdf_fname, sdf_lineno);
+		  return;
 	    }
 
 	    while ((vpi_port_bit = vpi_scan(iter))) {
@@ -216,6 +217,7 @@ void sdf_interconnect_delays(struct interconnect_port_s port1, struct interconne
 		  if (port1.index == bit) {
 			if (sdf_flag_inform) vpi_printf("SDF INFO: %s:%d: Substituting vpiPort with vpiPortBit for port1\n", sdf_fname, sdf_lineno);
 			port1_handle = vpi_port_bit;
+			vpi_release_handle(iter); // Free the iterator
 			break;
 		  }
 	    }
@@ -228,6 +230,7 @@ void sdf_interconnect_delays(struct interconnect_port_s port1, struct interconne
 
 	    if (!iter) {
 		  vpi_printf("SDF ERROR: %s:%d: Could not find vpiBit iterator for port2!\n", sdf_fname, sdf_lineno);
+		  return;
 	    }
 
 	    while ((vpi_port_bit = vpi_scan(iter))) {
@@ -237,6 +240,7 @@ void sdf_interconnect_delays(struct interconnect_port_s port1, struct interconne
 		  if (port2.index == bit) {
 			if (sdf_flag_inform) vpi_printf("SDF INFO: %s:%d: Substituting vpiPort with vpiPortBit for port2\n", sdf_fname, sdf_lineno);
 			port2_handle = vpi_port_bit;
+			vpi_release_handle(iter); // Free the iterator
 			break;
 		  }
 	    }
diff --git a/vpi_modules.cc b/vpi_modules.cc
index ab8f86f7c..26ccd395f 100644
--- a/vpi_modules.cc
+++ b/vpi_modules.cc
@@ -96,6 +96,7 @@ PLI_INT32   vpi_vprintf(const char*, va_list) { return 0; }
 PLI_INT32   vpi_chk_error(p_vpi_error_info) { return 0; }
 PLI_INT32   vpi_compare_objects(vpiHandle, vpiHandle) { return 0; }
 PLI_INT32   vpi_free_object(vpiHandle) { return 0; }
+PLI_INT32   vpi_release_handle(vpiHandle) { return 0; }
 PLI_INT32   vpi_get_vlog_info(p_vpi_vlog_info info)
 {
     info->argc = 0;
diff --git a/vpi_user.h b/vpi_user.h
index a35ce5d15..40bf4879d 100644
--- a/vpi_user.h
+++ b/vpi_user.h
@@ -567,6 +567,7 @@ extern vpiHandle vpi_put_value(vpiHandle obj, p_vpi_value value,
 			       p_vpi_time when, PLI_INT32 flags);
 
 extern PLI_INT32 vpi_free_object(vpiHandle ref);
+extern PLI_INT32 vpi_release_handle(vpiHandle ref);
 extern PLI_INT32 vpi_get_vlog_info(p_vpi_vlog_info vlog_info_p);
 
 /*
@@ -724,6 +725,7 @@ typedef struct {
     PLI_INT32   (*chk_error)(p_vpi_error_info);
     PLI_INT32   (*compare_objects)(vpiHandle, vpiHandle);
     PLI_INT32   (*free_object)(vpiHandle);
+    PLI_INT32   (*release_handle)(vpiHandle);
     PLI_INT32   (*get_vlog_info)(p_vpi_vlog_info info) ;
     void        (*vcontrol)(PLI_INT32, va_list);
     PLI_INT32   (*fopen)(const char*, const char*);
diff --git a/vvp/vpi_priv.cc b/vvp/vpi_priv.cc
index f92fdeea1..6d6422d56 100644
--- a/vvp/vpi_priv.cc
+++ b/vvp/vpi_priv.cc
@@ -291,6 +291,14 @@ PLI_INT32 vpi_free_object(vpiHandle ref)
       return rtn;
 }
 
+PLI_INT32 vpi_release_handle(vpiHandle ref)
+{
+	// Since SystemVerilog vpi_free_object() has been
+	// renamed vpi_release_handle(), and thus
+	// vpi_free_object() has been deprecated.
+      return vpi_free_object(ref);
+}
+
 static int vpip_get_global(int property)
 {
       switch (property) {
@@ -1575,7 +1583,7 @@ bool check_connected_to_concat8(vvp_net_t* current_net, vvp_net_t* net2)
 
 	      // net2 is connected
 	    if (cur.ptr() == net2) {
-		    return true;
+		  return true;
 	    }
 
 	      // Next net in linked list
@@ -2002,6 +2010,7 @@ vpip_routines_s vpi_routines = {
     .chk_error                  = vpi_chk_error,
     .compare_objects            = vpi_compare_objects,
     .free_object                = vpi_free_object,
+    .release_handle             = vpi_release_handle,
     .get_vlog_info              = vpi_get_vlog_info,
     .vcontrol                   = vpi_sim_vcontrol,
     .fopen                      = vpi_fopen,
diff --git a/vvp/vvp.def b/vvp/vvp.def
index 7e7da212c..cbc478bbb 100644
--- a/vvp/vvp.def
+++ b/vvp/vvp.def
@@ -32,6 +32,7 @@ vpi_put_userdata
 vpi_put_value
 vpi_register_cb
 vpi_register_systf
+vpi_release_handle
 vpi_remove_cb
 vpi_scan
 vpi_sim_control