diff --git a/CMakeLists.txt b/CMakeLists.txt
index d8501f1..7ad3e17 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -6,6 +6,7 @@ project(sngrep
 set(PROJECT_NAME sngrep)
 set(CMAKE_C_STANDARD 99)
 add_compile_options(-Werror)
+#add_compile_options(-Werror -Wall -pedantic -Wextra)
 
 configure_file(
     ${PROJECT_SOURCE_DIR}/src/config.h.cmake.in
diff --git a/src/capture/capture.c b/src/capture/capture.c
index 82345f0..d508866 100644
--- a/src/capture/capture.c
+++ b/src/capture/capture.c
@@ -81,7 +81,7 @@ capture_manager_start(CaptureManager *manager)
     for (GSList *le = manager->inputs; le != NULL; le = le->next) {
         CaptureInput *input = le->data;
         input->running = TRUE;
-        input->thread = g_thread_new(NULL, (void *) input->start, input);
+        input->thread = g_thread_new(NULL, (GThreadFunc) input->start, input);
     }
 }
 
@@ -132,7 +132,7 @@ capture_manager_filter(CaptureManager *manager)
 }
 
 void
-capture_manager_set_keyfile(CaptureManager *manager, gchar *keyfile, GError **error)
+capture_manager_set_keyfile(CaptureManager *manager, gchar *keyfile, G_GNUC_UNUSED GError **error)
 {
     manager->keyfile = keyfile;
 }
diff --git a/src/capture/capture_pcap.c b/src/capture/capture_pcap.c
index ead5eef..dc81d86 100644
--- a/src/capture/capture_pcap.c
+++ b/src/capture/capture_pcap.c
@@ -85,7 +85,7 @@ capture_input_pcap_online(const gchar *dev, GError **error)
     pcap->link = pcap_datalink(pcap->handle);
 
     // Check linktypes sngrep knowns before start parsing packets
-    if (proto_link_size(pcap->link) == -1) {
+    if (proto_link_size(pcap->link) == 0) {
         g_set_error (error,
                      CAPTURE_PCAP_ERROR,
                      CAPTURE_PCAP_ERROR_UNKNOWN_LINK,
@@ -142,7 +142,7 @@ capture_input_pcap_offline(const gchar *infile, GError **error)
     pcap->link = pcap_datalink(pcap->handle);
 
     // Check linktypes sngrep knowns before start parsing packets
-    if (proto_link_size(pcap->link) == -1) {
+    if (proto_link_size(pcap->link) == 0) {
         g_set_error (error,
                      CAPTURE_PCAP_ERROR,
                      CAPTURE_PCAP_ERROR_UNKNOWN_LINK,
@@ -307,11 +307,9 @@ capture_pcap_parse_packet(u_char *info, const struct pcap_pkthdr *header, const
 
     // Capture Input info
     CaptureInput *input = (CaptureInput *) info;
-    // Capture pcap info
-    CapturePcap *pcap = input->priv;
     // Capture manager
     CaptureManager *manager = input->manager;
-    //
+    // Packet dissectors parser
     PacketParser *parser = input->parser;
 
     // Ignore packets while capture is paused
diff --git a/src/curses/ui_call_flow.c b/src/curses/ui_call_flow.c
index 9759183..b9212cb 100644
--- a/src/curses/ui_call_flow.c
+++ b/src/curses/ui_call_flow.c
@@ -430,7 +430,7 @@ call_flow_draw_message(ui_t *ui, call_flow_arrow_t *arrow, int cline)
     Address src;
     Address dst;
     char method[80];
-    char delta[15] = { };
+    char delta[15] = { 0 };
     int flowh;
     char mediastr[40];
     SipMsg *msg = arrow->item;
diff --git a/src/curses/ui_call_list.c b/src/curses/ui_call_list.c
index 5cbf554..3983eb7 100644
--- a/src/curses/ui_call_list.c
+++ b/src/curses/ui_call_list.c
@@ -160,7 +160,7 @@ call_list_info(ui_t *ui)
 }
 
 bool
-call_list_redraw(ui_t *ui)
+call_list_redraw(G_GNUC_UNUSED ui_t *ui)
 {
     return storage_calls_changed();
 }
diff --git a/src/packet/address.c b/src/packet/address.c
index 8c3a583..0aba9c5 100644
--- a/src/packet/address.c
+++ b/src/packet/address.c
@@ -105,7 +105,7 @@ address_is_local(Address addr)
 Address
 address_from_str(const char *ipport)
 {
-    Address ret = {};
+    Address ret = { 0 };
     gchar scanipport[256];
     gchar address[256];
     guint16 port;
@@ -115,7 +115,7 @@ address_from_str(const char *ipport)
 
     strncpy(scanipport, ipport, strlen(ipport));
 
-    if (sscanf(scanipport, "%[^:]:%hd", address, &port) == 2) {
+    if (sscanf(scanipport, "%[^:]:%hu", address, &port) == 2) {
         strncpy(ret.ip, address, strlen(address));
         ret.port = port;
     }
diff --git a/src/packet/dissectors/packet_ip.c b/src/packet/dissectors/packet_ip.c
index 2064873..3e3d8df 100644
--- a/src/packet/dissectors/packet_ip.c
+++ b/src/packet/dissectors/packet_ip.c
@@ -195,6 +195,8 @@ packet_ip_parse(PacketParser *parser, Packet *packet, GByteArray *data)
         // Call next dissector
         return packet_parser_next_dissector(parser, packet, data);
     }
+
+    return data;
 }
 
 static void
diff --git a/src/packet/dissectors/packet_link.c b/src/packet/dissectors/packet_link.c
index d35a594..d8654b1 100644
--- a/src/packet/dissectors/packet_link.c
+++ b/src/packet/dissectors/packet_link.c
@@ -45,7 +45,7 @@ packet_link_parse(PacketParser *parser, Packet *packet, GByteArray *data)
     g_return_val_if_fail(priv, NULL);
 
     // Get Layer header size from link type
-    gint offset = priv->link_size;
+    guint offset = (guint) priv->link_size;
 
     // For ethernet, skip VLAN header if present
     if (priv->link_type == DLT_EN10MB) {
@@ -162,7 +162,7 @@ packet_link_init(PacketParser *parser)
 }
 
 static void
-packet_link_deinit(PacketParser *parser)
+packet_link_deinit(G_GNUC_UNUSED PacketParser *parser)
 {
 //    g_free(proto->priv);
 //    g_free(proto);
diff --git a/src/packet/dissectors/packet_rtcp.c b/src/packet/dissectors/packet_rtcp.c
index 561d946..fae5f02 100644
--- a/src/packet/dissectors/packet_rtcp.c
+++ b/src/packet/dissectors/packet_rtcp.c
@@ -91,7 +91,7 @@ packet_rtcp_parse(G_GNUC_UNUSED PacketParser *parser, Packet *packet, GByteArray
             break;
 
         // Header length
-        gint hlen = g_ntohs(hdr.len) * 4 + 4;
+        guint hlen = (guint) g_ntohs(hdr.len) * 4 + 4;
 
         // No enough data for this RTCP header
         if (hlen > data->len)
@@ -117,7 +117,7 @@ packet_rtcp_parse(G_GNUC_UNUSED PacketParser *parser, Packet *packet, GByteArray
                 size_t bsize = sizeof(hdr_xr);
 
                 // Read all report blocks
-                while (bsize < ntohs(hdr_xr.len) * 4 + 4) {
+                while (bsize < (guint) ntohs(hdr_xr.len) * 4 + 4) {
                     // Read block header
                     memcpy(&blk_xr, data->data + bsize, sizeof(blk_xr));
                     // Check block type
diff --git a/src/packet/dissectors/packet_sdp.c b/src/packet/dissectors/packet_sdp.c
index 2fb6e27..9c72350 100644
--- a/src/packet/dissectors/packet_sdp.c
+++ b/src/packet/dissectors/packet_sdp.c
@@ -227,6 +227,8 @@ packet_sdp_dissect(G_GNUC_UNUSED PacketParser *parser, Packet *packet, GByteArra
 
     // Set packet SDP data
     g_ptr_array_insert(packet->proto, PACKET_SDP, sdp);
+
+    return data;
 }
 
 PacketDissector *
diff --git a/src/packet/dissectors/packet_sip.c b/src/packet/dissectors/packet_sip.c
index 30dd5e4..6443458 100644
--- a/src/packet/dissectors/packet_sip.c
+++ b/src/packet/dissectors/packet_sip.c
@@ -172,14 +172,14 @@ packet_sip_parse(PacketParser *parser, Packet *packet, GByteArray *data)
     gint start, end;
 
     // Only handle UTF-8 SIP payloads
-    if (!g_utf8_validate(data->data, data->len, NULL)) {
+    if (!g_utf8_validate((gchar *) data->data, data->len, NULL)) {
         return data;
     }
 
     DissectorSipData *sip = g_ptr_array_index(parser->dissectors, PACKET_SIP);
 
     // Convert payload to something we can parse with regular expressions
-    GString *payload = g_string_new_len(data->data, data->len);
+    GString *payload = g_string_new_len((const gchar *) data->data, data->len);
 
     // If this comes from a TCP stream, check we have a whole packet
     if (packet_has_type(packet, PACKET_TCP)) {
@@ -204,14 +204,14 @@ packet_sip_parse(PacketParser *parser, Packet *packet, GByteArray *data)
         g_match_info_fetch_pos(pmatch, 1, &start, &end);
 
         // The SDP body of the SIP message ends in another packet
-        if (start + content_len > data->len) {
+        if ((guint) (start + content_len) > data->len) {
             g_match_info_free(pmatch);
             // Not a SIP message or not complete
             return data;
         }
 
         // We got more than one SIP message in the same packet
-        if (start + content_len < data->len) {
+        if ((guint) (start + content_len) < data->len) {
             // Limit the size of the string to the end of the body
             g_string_set_size(payload, start + content_len);
         }
diff --git a/src/packet/dissectors/packet_tcp.c b/src/packet/dissectors/packet_tcp.c
index 9758428..f22ac9e 100644
--- a/src/packet/dissectors/packet_tcp.c
+++ b/src/packet/dissectors/packet_tcp.c
@@ -248,6 +248,8 @@ packet_tcp_parse(PacketParser *parser, Packet *packet, GByteArray *data)
     } else if (pending->len < data->len) {
         // Partially parsed
     }
+
+    return pending;
 }
 
 static void
diff --git a/src/packet/old_packet.h b/src/packet/old_packet.h
index 3492ca3..de4ef9c 100644
--- a/src/packet/old_packet.h
+++ b/src/packet/old_packet.h
@@ -33,8 +33,8 @@
  *
  */
 
-#ifndef __SNGREP_CAPTURE_PACKET_H
-#define __SNGREP_CAPTURE_PACKET_H
+#ifndef __SNGREP_CAPTURE_OLD_PACKET_H
+#define __SNGREP_CAPTURE_OLD_PACKET_H
 
 #include <time.h>
 #include <sys/types.h>
@@ -173,4 +173,4 @@ packet_payload(packet_t *packet);
 struct timeval
 packet_time(const packet_t *packet);
 
-#endif /* __SNGREP_CAPTURE_PACKET_H */
+#endif /* __SNGREP_CAPTURE_OLD_PACKET_H */
diff --git a/src/packet/packet.c b/src/packet/packet.c
index 8a33dd4..9340397 100644
--- a/src/packet/packet.c
+++ b/src/packet/packet.c
@@ -144,7 +144,7 @@ packet_to_oldpkt(Packet *packet)
 
     PacketSipData *sipdata = g_ptr_array_index(packet->proto, PACKET_SIP);
     if (sipdata) {
-        packet_set_payload(oldpkt, sipdata->payload, strlen(sipdata->payload));
+        packet_set_payload(oldpkt, (guchar *) sipdata->payload, strlen(sipdata->payload));
     }
 
     oldpkt->frames = g_sequence_new(NULL);
diff --git a/src/packet/parser.c b/src/packet/parser.c
index 1757119..780ded4 100644
--- a/src/packet/parser.c
+++ b/src/packet/parser.c
@@ -113,6 +113,8 @@ packet_parser_add_proto(PacketParser *parser, GNode *parent, enum packet_proto i
     for (GSList *l = dissector->subdissectors; l != NULL; l = l->next) {
         packet_parser_add_proto(parser, node, GPOINTER_TO_UINT(l->data));
     }
+
+    return dissector;
 }