diff --git a/tshark.c b/tshark.c

index 00c28db781..e02b61b663 100644

--- a/tshark.c

+++ b/tshark.c

@@ -1977,10 +1977,10 @@ real_main(int argc, char *argv[])

       /* Activate the export PDU tap */

       comment = g_strdup_printf("Dump of PDUs from %s", cf_name);

       err = exp_pdu_open(&exp_pdu_tap_data, exp_fd, comment);

+      g_free(comment);

       if (err != 0) {

           cfile_dump_open_failure_message("TShark", exp_pdu_filename, err,

                                           WTAP_FILE_TYPE_SUBTYPE_PCAPNG);

-          g_free(comment);

           exit_status = INVALID_EXPORT;

           goto clean_exit;

       }

diff --git a/ui/export_pdu_ui_utils.c b/ui/export_pdu_ui_utils.c

index a567a61991..c9e40b7a24 100644

--- a/ui/export_pdu_ui_utils.c

+++ b/ui/export_pdu_ui_utils.c

@@ -43,8 +43,8 @@ exp_pdu_file_open(exp_pdu_t *exp_pdu_tap_data)

     comment = g_strdup_printf("Dump of PDUs from %s", cfile.filename);

     err = exp_pdu_open(exp_pdu_tap_data, import_file_fd, comment);

+    g_free(comment);

     if (err != 0) {

-        g_free(comment);

         cfile_dump_open_failure_alert_box(capfile_name ? capfile_name : "temporary file",

                                           err, WTAP_FILE_TYPE_SUBTYPE_PCAPNG);

         goto end;

diff --git a/ui/tap_export_pdu.c b/ui/tap_export_pdu.c

index 25232f0452..d3302a5aca 100644

--- a/ui/tap_export_pdu.c

+++ b/ui/tap_export_pdu.c

@@ -82,7 +82,7 @@ export_pdu_packet(void *tapdata, packet_info *pinfo, epan_dissect_t *edt, const

 }

 int

-exp_pdu_open(exp_pdu_t *exp_pdu_tap_data, int fd, char *comment)

+exp_pdu_open(exp_pdu_t *exp_pdu_tap_data, int fd, const char *comment)

 {

     int   err;

@@ -103,7 +103,6 @@ exp_pdu_open(exp_pdu_t *exp_pdu_tap_data, int fd, char *comment)

     /* options */

     wtap_block_add_string_option(shb_hdr, OPT_COMMENT, comment, strlen(comment));

-    g_free(comment);

     /*

      * UTF-8 string containing the name of the operating system used to create

diff --git a/ui/tap_export_pdu.h b/ui/tap_export_pdu.h

index ea5c4077e1..9ae2dea65f 100644

--- a/ui/tap_export_pdu.h

+++ b/ui/tap_export_pdu.h

@@ -41,7 +41,7 @@ char *exp_pdu_pre_open(const char *tap_name, const char *filter,

 *

 * @return 0 on success or a wtap error code.

 */

-int exp_pdu_open(exp_pdu_t *data, int fd, char *comment);

+int exp_pdu_open(exp_pdu_t *data, int fd, const char *comment);

 /* Stops the PDUs export. */

 int exp_pdu_close(exp_pdu_t *exp_pdu_tap_data);

diff --git a/ui/cli/tap-wspstat.c b/ui/cli/tap-wspstat.c

index 22862cdaf8..fd6f3ad427 100644

--- a/ui/cli/tap-wspstat.c

+++ b/ui/cli/tap-wspstat.c

@@ -252,9 +252,9 @@ wspstat_init(const char *opt_arg, void *userdata _U_)

 		/* error, we failed to attach to the tap. clean up */

 		g_free(sp->pdu_stats);

 		g_free(sp->filter);

-		g_free(sp);

 		g_hash_table_foreach( sp->hash, (GHFunc) wsp_free_hash_table, NULL ) ;

 		g_hash_table_destroy( sp->hash );

+		g_free(sp);

 		fprintf(stderr, "tshark: Couldn't register wsp,stat tap: %s\n",

 				error_string->str);

 		g_string_free(error_string, TRUE);

diff --git a/epan/dissectors/packet-isobus-vt.c b/epan/dissectors/packet-isobus-vt.c

index 1f9fa98..79f1c1f 100644

--- a/epan/dissectors/packet-isobus-vt.c

+++ b/epan/dissectors/packet-isobus-vt.c

@@ -1546,16 +1546,8 @@ dissect_vt(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree, enum vt_directio

             }

             else

             {

-                if(status == 0)

-                {

-                    col_append_fstr(pinfo->cinfo, COL_INFO, "Status of Auxiliary Input %s was successfully changed to enabled",

-                        get_object_id_string(auxiliary_input_object_id));

-                }

-                else

-                {

-                    col_append_fstr(pinfo->cinfo, COL_INFO, "Status of Auxiliary Input %s was successfully changed to enabled",

-                        get_object_id_string(auxiliary_input_object_id));

-                }

+                col_append_fstr(pinfo->cinfo, COL_INFO, "Status of Auxiliary Input %s was successfully changed to enabled",

+                    get_object_id_string(auxiliary_input_object_id));

             }

         }

     }

diff --git a/epan/dfilter/dfilter.c b/epan/dfilter/dfilter.c

index a975f84..3e440b3 100644

--- a/epan/dfilter/dfilter.c

+++ b/epan/dfilter/dfilter.c

@@ -221,6 +221,7 @@ dfilter_compile(const gchar *text, dfilter_t **dfp, gchar **err_msg)

 	}

 	if ( !( expanded_text = dfilter_macro_apply(text, err_msg) ) ) {

+		*dfp = NULL;

 		return FALSE;

 	}