diff --git a/src/internal.h b/src/internal.h
index c054e3ce96..3bab6b4bfe 100644
--- a/src/internal.h
+++ b/src/internal.h
@@ -174,6 +174,10 @@
     _Pragma ("GCC diagnostic push")
 #endif
 
+#define VIR_WARNINGS_NO_UNUSED_FUNCTION \
+    _Pragma ("GCC diagnostic push") \
+    _Pragma ("GCC diagnostic ignored \"-Wunused-function\"")
+
 /* Workaround bogus GCC 6.0 for logical 'or' equal expression warnings.
  * (GCC bz 69602) */
 #if BROKEN_GCC_WLOGICALOP_EQUAL_EXPR
diff --git a/tools/Makefile.am b/tools/Makefile.am
index 53df930e0a..eb8f269b48 100644
--- a/tools/Makefile.am
+++ b/tools/Makefile.am
@@ -378,7 +378,7 @@ if WITH_WIRESHARK_DISSECTOR
 
 ws_plugin_LTLIBRARIES = wireshark/src/libvirt.la
 wireshark_src_libvirt_la_CFLAGS = \
-	-I wireshark/src $(WIRESHARK_DISSECTOR_CFLAGS) $(XDR_CFLAGS)
+	-I wireshark/src $(WIRESHARK_DISSECTOR_CFLAGS) $(XDR_CFLAGS) $(AM_CFLAGS)
 wireshark_src_libvirt_la_LDFLAGS = -avoid-version -module
 wireshark_src_libvirt_la_SOURCES = \
 	wireshark/src/packet-libvirt.h \
diff --git a/tools/wireshark/src/packet-libvirt.c b/tools/wireshark/src/packet-libvirt.c
index 20b7a3ec81..2b499d2cf2 100644
--- a/tools/wireshark/src/packet-libvirt.c
+++ b/tools/wireshark/src/packet-libvirt.c
@@ -75,6 +75,8 @@ static gint ett_libvirt_stream_hole = -1;
         } \
     }
 
+VIR_WARNINGS_NO_UNUSED_FUNCTION
+
 XDR_PRIMITIVE_DISSECTOR(int,     gint32,  int)
 XDR_PRIMITIVE_DISSECTOR(u_int,   guint32, uint)
 XDR_PRIMITIVE_DISSECTOR(short,   gint16,  int)
@@ -87,6 +89,8 @@ XDR_PRIMITIVE_DISSECTOR(float,   gfloat,  float)
 XDR_PRIMITIVE_DISSECTOR(double,  gdouble, double)
 XDR_PRIMITIVE_DISSECTOR(bool,    bool_t,  boolean)
 
+VIR_WARNINGS_RESET
+
 typedef gboolean (*vir_xdr_dissector_t)(tvbuff_t *tvb, proto_tree *tree, XDR *xdrs, int hf);
 
 typedef struct vir_dissector_index vir_dissector_index_t;
@@ -345,7 +349,9 @@ dissect_libvirt_num_of_fds(tvbuff_t *tvb, proto_tree *tree)
 }
 
 static void
-dissect_libvirt_fds(tvbuff_t *tvb, gint start, gint32 nfds)
+dissect_libvirt_fds(tvbuff_t *tvb G_GNUC_UNUSED,
+                    gint start G_GNUC_UNUSED,
+                    gint32 nfds G_GNUC_UNUSED)
 {
     /* TODO: NOP for now */
 }
@@ -420,8 +426,13 @@ dissect_libvirt_payload(tvbuff_t *tvb, proto_tree *tree,
         return; /* No payload */
 
     if (status == VIR_NET_OK) {
-        vir_xdr_dissector_t xd = find_payload_dissector(proc, type, get_program_data(prog, VIR_PROGRAM_DISSECTORS),
-                                                        *(gsize *)get_program_data(prog, VIR_PROGRAM_DISSECTORS_LEN));
+        const vir_dissector_index_t *pds = get_program_data(prog, VIR_PROGRAM_DISSECTORS);
+        const gsize *len = get_program_data(prog, VIR_PROGRAM_DISSECTORS_LEN);
+
+        if (!len)
+            goto unknown;
+
+        vir_xdr_dissector_t xd = find_payload_dissector(proc, type, pds, *len);
         if (xd == NULL)
             goto unknown;
         dissect_libvirt_payload_xdr_data(tvb, tree, payload_length, status, xd);