diff --git a/server/modules/filter/CMakeLists.txt b/server/modules/filter/CMakeLists.txt
index 647d117e8..a4bc9048f 100644
--- a/server/modules/filter/CMakeLists.txt
+++ b/server/modules/filter/CMakeLists.txt
@@ -1,18 +1,18 @@
+add_subdirectory(binlogfilter)
 add_subdirectory(cache)
-add_subdirectory(maxrows)
 add_subdirectory(ccrfilter)
 add_subdirectory(dbfwfilter)
 add_subdirectory(hintfilter)
+add_subdirectory(insertstream)
 add_subdirectory(luafilter)
+add_subdirectory(masking)
+add_subdirectory(maxrows)
 add_subdirectory(mqfilter)
 add_subdirectory(namedserverfilter)
 add_subdirectory(nullfilter)
 add_subdirectory(qlafilter)
 add_subdirectory(regexfilter)
 add_subdirectory(tee)
+add_subdirectory(throttlefilter)
 add_subdirectory(topfilter)
 add_subdirectory(tpmfilter)
-add_subdirectory(masking)
-add_subdirectory(insertstream)
-add_subdirectory(binlogfilter)
-add_subdirectory(throttlefilter)
diff --git a/server/modules/filter/ccrfilter/CMakeLists.txt b/server/modules/filter/ccrfilter/CMakeLists.txt
index 672688725..afcc04f8f 100644
--- a/server/modules/filter/ccrfilter/CMakeLists.txt
+++ b/server/modules/filter/ccrfilter/CMakeLists.txt
@@ -1,4 +1,4 @@
-add_library(ccrfilter SHARED ccrfilter.c)
+add_library(ccrfilter SHARED ccrfilter.cc)
 target_link_libraries(ccrfilter maxscale-common)
 set_target_properties(ccrfilter PROPERTIES VERSION "1.0.0")
 install_module(ccrfilter core)
diff --git a/server/modules/filter/ccrfilter/ccrfilter.c b/server/modules/filter/ccrfilter/ccrfilter.cc
similarity index 97%
rename from server/modules/filter/ccrfilter/ccrfilter.c
rename to server/modules/filter/ccrfilter/ccrfilter.cc
index 75437d8f7..86dc97d66 100644
--- a/server/modules/filter/ccrfilter/ccrfilter.c
+++ b/server/modules/filter/ccrfilter/ccrfilter.cc
@@ -119,6 +119,9 @@ typedef enum ccr_hint_value_t
 
 static CCR_HINT_VALUE search_ccr_hint(GWBUF* buffer);
 
+extern "C"
+{
+
 /**
  * The module entry point routine. It is this routine that
  * must populate the structure that is referred to as the
@@ -177,6 +180,8 @@ MXS_MODULE* MXS_CREATE_MODULE()
     return &info;
 }
 
+}
+
 /**
  * Create an instance of the filter for a particular service
  * within MaxScale.
@@ -190,7 +195,7 @@ MXS_MODULE* MXS_CREATE_MODULE()
 static MXS_FILTER *
 createInstance(const char *name, char **options, MXS_CONFIG_PARAMETER *params)
 {
-    CCR_INSTANCE *my_instance = MXS_CALLOC(1, sizeof(CCR_INSTANCE));
+    CCR_INSTANCE *my_instance = static_cast<CCR_INSTANCE*>(MXS_CALLOC(1, sizeof(CCR_INSTANCE)));
 
     if (my_instance)
     {
@@ -237,7 +242,7 @@ static MXS_FILTER_SESSION *
 newSession(MXS_FILTER *instance, MXS_SESSION *session)
 {
     CCR_INSTANCE *my_instance = (CCR_INSTANCE *)instance;
-    CCR_SESSION  *my_session = MXS_MALLOC(sizeof(CCR_SESSION));
+    CCR_SESSION  *my_session = static_cast<CCR_SESSION*>(MXS_MALLOC(sizeof(CCR_SESSION)));
 
     if (my_session)
     {
@@ -490,14 +495,14 @@ static CCR_HINT_VALUE search_ccr_hint(GWBUF* buffer)
 
     while (hint && !found_ccr)
     {
-        if (hint->type == HINT_PARAMETER && strcasecmp(hint->data, CCR) == 0)
+        if (hint->type == HINT_PARAMETER && strcasecmp(static_cast<char*>(hint->data), CCR) == 0)
         {
             found_ccr = true;
-            if (strcasecmp(hint->value, "match") == 0)
+            if (strcasecmp(static_cast<char*>(hint->value), "match") == 0)
             {
                 rval = CCR_HINT_MATCH;
             }
-            else if (strcasecmp(hint->value, "ignore") == 0)
+            else if (strcasecmp(static_cast<char*>(hint->value), "ignore") == 0)
             {
                 rval = CCR_HINT_IGNORE;
             }
diff --git a/server/modules/filter/hintfilter/CMakeLists.txt b/server/modules/filter/hintfilter/CMakeLists.txt
index 7bd06705b..2b01b8826 100644
--- a/server/modules/filter/hintfilter/CMakeLists.txt
+++ b/server/modules/filter/hintfilter/CMakeLists.txt
@@ -1,4 +1,4 @@
-add_library(hintfilter SHARED hintfilter.c hintparser.c)
+add_library(hintfilter SHARED hintfilter.cc hintparser.cc)
 set_target_properties(hintfilter PROPERTIES INSTALL_RPATH ${CMAKE_INSTALL_RPATH}:${MAXSCALE_LIBDIR} VERSION "1.0.0")
 target_link_libraries(hintfilter maxscale-common)
 install_module(hintfilter core)
diff --git a/server/modules/filter/hintfilter/hintfilter.c b/server/modules/filter/hintfilter/hintfilter.cc
similarity index 97%
rename from server/modules/filter/hintfilter/hintfilter.c
rename to server/modules/filter/hintfilter/hintfilter.cc
index 87541e148..ea285cc0c 100644
--- a/server/modules/filter/hintfilter/hintfilter.c
+++ b/server/modules/filter/hintfilter/hintfilter.cc
@@ -36,6 +36,9 @@ static void diagnostic(MXS_FILTER *instance, MXS_FILTER_SESSION *fsession, DCB *
 static json_t* diagnostic_json(const MXS_FILTER *instance, const MXS_FILTER_SESSION *fsession);
 static uint64_t getCapabilities(MXS_FILTER* instance);
 
+extern "C"
+{
+
 /**
  * The module entry point routine. It is this routine that
  * must populate the structure that is referred to as the
@@ -83,6 +86,8 @@ MXS_MODULE* MXS_CREATE_MODULE()
     return &info;
 }
 
+}
+
 /**
  * Create an instance of the filter for a particular service
  * within MaxScale.
@@ -98,7 +103,7 @@ createInstance(const char *name, char **options, MXS_CONFIG_PARAMETER *params)
 {
     HINT_INSTANCE *my_instance;
 
-    if ((my_instance = MXS_CALLOC(1, sizeof(HINT_INSTANCE))) != NULL)
+    if ((my_instance = static_cast<HINT_INSTANCE*>(MXS_CALLOC(1, sizeof(HINT_INSTANCE)))) != NULL)
     {
         my_instance->sessions = 0;
     }
@@ -118,7 +123,7 @@ newSession(MXS_FILTER *instance, MXS_SESSION *session)
     HINT_INSTANCE *my_instance = (HINT_INSTANCE *)instance;
     HINT_SESSION *my_session;
 
-    if ((my_session = MXS_CALLOC(1, sizeof(HINT_SESSION))) != NULL)
+    if ((my_session = static_cast<HINT_SESSION*>(MXS_CALLOC(1, sizeof(HINT_SESSION)))) != NULL)
     {
         my_session->query_len = 0;
         my_session->request = NULL;
diff --git a/server/modules/filter/hintfilter/hintparser.c b/server/modules/filter/hintfilter/hintparser.cc
similarity index 99%
rename from server/modules/filter/hintfilter/hintparser.c
rename to server/modules/filter/hintfilter/hintparser.cc
index f0dd24712..f4936b0a4 100644
--- a/server/modules/filter/hintfilter/hintparser.c
+++ b/server/modules/filter/hintfilter/hintparser.cc
@@ -33,7 +33,7 @@
  */
 struct
 {
-    char *keyword;
+    const char *keyword;
     TOKEN_VALUE token;
 } keywords[] =
 {
@@ -49,7 +49,7 @@ struct
     { "master", TOK_MASTER},
     { "slave", TOK_SLAVE},
     { "server", TOK_SERVER},
-    { NULL, 0}
+    { NULL, static_cast<TOKEN_VALUE>(0)}
 };
 /**
 HINT_TOKEN kwords[] = {
@@ -600,7 +600,7 @@ hint_next_token(GWBUF **buf, char **ptr)
         if (*ptr > (char *)((*buf)->end) && (*buf)->next)
         {
             *buf = (*buf)->next;
-            *ptr = (*buf)->start;
+            *ptr = static_cast<char*>((*buf)->start);
         }
 
         if (dest - word > 98)
diff --git a/server/modules/filter/insertstream/CMakeLists.txt b/server/modules/filter/insertstream/CMakeLists.txt
index 54dd18349..88044a863 100644
--- a/server/modules/filter/insertstream/CMakeLists.txt
+++ b/server/modules/filter/insertstream/CMakeLists.txt
@@ -1,4 +1,4 @@
-add_library(insertstream SHARED insertstream.c)
+add_library(insertstream SHARED insertstream.cc)
 target_link_libraries(insertstream maxscale-common mysqlcommon)
 set_target_properties(insertstream PROPERTIES VERSION "1.0.0")
 install_module(insertstream core)
diff --git a/server/modules/filter/insertstream/insertstream.c b/server/modules/filter/insertstream/insertstream.cc
similarity index 98%
rename from server/modules/filter/insertstream/insertstream.c
rename to server/modules/filter/insertstream/insertstream.cc
index 86b6a35ec..6805842e2 100644
--- a/server/modules/filter/insertstream/insertstream.c
+++ b/server/modules/filter/insertstream/insertstream.cc
@@ -78,6 +78,9 @@ typedef struct
     char target[MYSQL_TABLE_MAXLEN + MYSQL_DATABASE_MAXLEN + 1]; /**< Current target table */
 } DS_SESSION;
 
+extern "C"
+{
+
 /**
  * The module entry point routine. It is this routine that
  * must populate the structure that is referred to as the
@@ -128,6 +131,8 @@ MXS_MODULE* MXS_CREATE_MODULE()
     return &info;
 }
 
+}
+
 /**
  * Free a insertstream instance.
  * @param instance instance to free
@@ -162,7 +167,7 @@ createInstance(const char *name, char **options, MXS_CONFIG_PARAMETER *params)
 {
     DS_INSTANCE *my_instance;
 
-    if ((my_instance = MXS_CALLOC(1, sizeof(DS_INSTANCE))) != NULL)
+    if ((my_instance = static_cast<DS_INSTANCE*>(MXS_CALLOC(1, sizeof(DS_INSTANCE)))) != NULL)
     {
         my_instance->source = config_copy_string(params, "source");
         my_instance->user = config_copy_string(params, "user");
@@ -184,7 +189,7 @@ newSession(MXS_FILTER *instance, MXS_SESSION *session)
     DS_INSTANCE *my_instance = (DS_INSTANCE *) instance;
     DS_SESSION *my_session;
 
-    if ((my_session = MXS_CALLOC(1, sizeof(DS_SESSION))) != NULL)
+    if ((my_session = static_cast<DS_SESSION*>(MXS_CALLOC(1, sizeof(DS_SESSION)))) != NULL)
     {
         my_session->target[0] = '\0';
         my_session->state = DS_STREAM_CLOSED;
@@ -354,7 +359,7 @@ static int32_t routeQuery(MXS_FILTER *instance, MXS_FILTER_SESSION *session, GWB
 
         if (send_empty)
         {
-            char empty_packet[] = {0, 0, 0, packet_num};
+            char empty_packet[] = {0, 0, 0, static_cast<char>(packet_num)};
             queue = gwbuf_alloc_and_load(sizeof(empty_packet), &empty_packet[0]);
         }
     }
@@ -418,7 +423,7 @@ static GWBUF* convert_to_stream(GWBUF* buffer, uint8_t packet_num)
     buffer = gwbuf_consume(buffer, (modptr - dataptr) - MYSQL_HEADER_LEN);
     char* header_start = (char*)GWBUF_DATA(buffer);
     char* store_end = dataptr = header_start + MYSQL_HEADER_LEN;
-    char* end = buffer->end;
+    char* end = static_cast<char*>(buffer->end);
     char* value;
     uint32_t valuesize;
 
@@ -622,7 +627,7 @@ static bool extract_insert_target(GWBUF *buffer, char* target, int len)
 
         if (tables)
         {
-            for (int i = 0; i < (size_t)n_tables; ++i)
+            for (int i = 0; i < n_tables; ++i)
             {
                 MXS_FREE(tables[i]);
             }
diff --git a/server/modules/filter/luafilter/CMakeLists.txt b/server/modules/filter/luafilter/CMakeLists.txt
index 70993a027..673eb0b43 100644
--- a/server/modules/filter/luafilter/CMakeLists.txt
+++ b/server/modules/filter/luafilter/CMakeLists.txt
@@ -2,7 +2,7 @@ if (BUILD_LUAFILTER)
   find_package(Lua)
   if(LUA_FOUND)
     include_directories(${LUA_INCLUDE_DIR})
-    add_library(luafilter SHARED luafilter.c)
+    add_library(luafilter SHARED luafilter.cc)
     set_target_properties(luafilter PROPERTIES VERSION "1.0.0")
     target_link_libraries(luafilter maxscale-common ${LUA_LIBRARIES})
     install_module(luafilter experimental)
diff --git a/server/modules/filter/luafilter/luafilter.c b/server/modules/filter/luafilter/luafilter.cc
similarity index 99%
rename from server/modules/filter/luafilter/luafilter.c
rename to server/modules/filter/luafilter/luafilter.cc
index 7f85850d7..4ceba5e40 100644
--- a/server/modules/filter/luafilter/luafilter.c
+++ b/server/modules/filter/luafilter/luafilter.cc
@@ -67,6 +67,9 @@ static void diagnostic(MXS_FILTER *instance, MXS_FILTER_SESSION *fsession, DCB *
 static json_t* diagnostic_json(const MXS_FILTER *instance, const MXS_FILTER_SESSION *fsession);
 static uint64_t getCapabilities(MXS_FILTER *instance);
 
+extern "C"
+{
+
 /**
  * The module entry point routine. It is this routine that
  * must populate the structure that is referred to as the
@@ -116,6 +119,8 @@ MXS_MODULE* MXS_CREATE_MODULE()
     return &info;
 }
 
+}
+
 static int id_pool = 0;
 static GWBUF *current_global_query = NULL;
 
diff --git a/server/modules/filter/maxrows/CMakeLists.txt b/server/modules/filter/maxrows/CMakeLists.txt
index 6dee7a01e..256a43303 100644
--- a/server/modules/filter/maxrows/CMakeLists.txt
+++ b/server/modules/filter/maxrows/CMakeLists.txt
@@ -1,4 +1,4 @@
-add_library(maxrows SHARED maxrows.c)
+add_library(maxrows SHARED maxrows.cc)
 target_link_libraries(maxrows maxscale-common)
 set_target_properties(maxrows PROPERTIES VERSION "1.0.0")
 set_target_properties(maxrows PROPERTIES LINK_FLAGS -Wl,-z,defs)
diff --git a/server/modules/filter/maxrows/maxrows.c b/server/modules/filter/maxrows/maxrows.cc
similarity index 98%
rename from server/modules/filter/maxrows/maxrows.c
rename to server/modules/filter/maxrows/maxrows.cc
index 15868bbc5..b0a1c6cbc 100644
--- a/server/modules/filter/maxrows/maxrows.c
+++ b/server/modules/filter/maxrows/maxrows.cc
@@ -82,6 +82,9 @@ static const MXS_ENUM_VALUE return_option_values[] =
 
 /* Global symbols of the Module */
 
+extern "C"
+{
+
 /**
  * The module entry point function, called when the module is loaded.
  *
@@ -148,6 +151,8 @@ MXS_MODULE* MXS_CREATE_MODULE()
     return &info;
 };
 
+}
+
 /* Implementation */
 
 typedef struct maxrows_config
@@ -233,7 +238,7 @@ static MXS_FILTER *createInstance(const char *name,
                                   char **options,
                                   MXS_CONFIG_PARAMETER *params)
 {
-    MAXROWS_INSTANCE *cinstance = MXS_CALLOC(1, sizeof(MAXROWS_INSTANCE));
+    MAXROWS_INSTANCE *cinstance = static_cast<MAXROWS_INSTANCE*>(MXS_CALLOC(1, sizeof(MAXROWS_INSTANCE)));
 
     if (cinstance)
     {
@@ -242,9 +247,10 @@ static MXS_FILTER *createInstance(const char *name,
                                                                   "max_resultset_rows");
         cinstance->config.max_resultset_size = config_get_size(params,
                                                                "max_resultset_size");
-        cinstance->config.m_return = config_get_enum(params,
-                                                     "max_resultset_return",
-                                                     return_option_values);
+        cinstance->config.m_return =
+            static_cast<maxrows_return_mode>(config_get_enum(params,
+                                                             "max_resultset_return",
+                                                             return_option_values));
         cinstance->config.debug = config_get_integer(params, "debug");
     }
 
@@ -873,6 +879,7 @@ static int handle_rows(MAXROWS_SESSION_DATA *csdata, GWBUF* buffer, size_t extra
 
             // We have at least one complete packet and we can process the command byte.
             int command = (int)MYSQL_GET_COMMAND(header);
+            int flags = 0;
 
             switch (command)
             {
@@ -933,7 +940,7 @@ static int handle_rows(MAXROWS_SESSION_DATA *csdata, GWBUF* buffer, size_t extra
                     break;
                 }
 
-                int flags = gw_mysql_get_byte2(header + MAXROWS_MYSQL_EOF_PACKET_FLAGS_OFFSET);
+                flags = gw_mysql_get_byte2(header + MAXROWS_MYSQL_EOF_PACKET_FLAGS_OFFSET);
 
                 // Check whether the EOF terminates the resultset or indicates MORE_RESULTS
                 if (!(flags & SERVER_MORE_RESULTS_EXIST))
@@ -1093,7 +1100,7 @@ static int send_eof_upstream(MAXROWS_SESSION_DATA *csdata)
     size_t offset = gwbuf_length(csdata->res.column_defs);
 
     /* Data to send + added EOF */
-    uint8_t *new_result = MXS_MALLOC(offset + MYSQL_EOF_PACKET_LEN);
+    uint8_t *new_result = static_cast<uint8_t*>(MXS_MALLOC(offset + MYSQL_EOF_PACKET_LEN));
 
     if (new_result)
     {
@@ -1197,7 +1204,7 @@ static int send_error_upstream(MAXROWS_SESSION_DATA *csdata)
     GWBUF *err_pkt;
     uint8_t hdr_err[MYSQL_ERR_PACKET_MIN_LEN];
     unsigned long bytes_copied;
-    char *err_msg_prefix = "Row limit/size exceeded for query: ";
+    const char *err_msg_prefix = "Row limit/size exceeded for query: ";
     int err_prefix_len = strlen(err_msg_prefix);
     unsigned long pkt_len = MYSQL_ERR_PACKET_MIN_LEN + err_prefix_len;
     unsigned long sql_len = gwbuf_length(csdata->input_sql) -
diff --git a/server/modules/filter/mqfilter/CMakeLists.txt b/server/modules/filter/mqfilter/CMakeLists.txt
index 283663a6d..deac6b43a 100644
--- a/server/modules/filter/mqfilter/CMakeLists.txt
+++ b/server/modules/filter/mqfilter/CMakeLists.txt
@@ -1,7 +1,7 @@
 find_package(RabbitMQ)
 if(RABBITMQ_FOUND)
   include_directories(${RABBITMQ_HEADERS})
-  add_library(mqfilter SHARED mqfilter.c)
+  add_library(mqfilter SHARED mqfilter.cc)
   target_link_libraries(mqfilter maxscale-common ${RABBITMQ_LIBRARIES})
   add_dependencies(mqfilter pcre2)
   set_target_properties(mqfilter PROPERTIES VERSION "1.0.2")
diff --git a/server/modules/filter/mqfilter/mqfilter.c b/server/modules/filter/mqfilter/mqfilter.cc
similarity index 97%
rename from server/modules/filter/mqfilter/mqfilter.c
rename to server/modules/filter/mqfilter/mqfilter.cc
index 477d420fb..ad6b6db40 100644
--- a/server/modules/filter/mqfilter/mqfilter.c
+++ b/server/modules/filter/mqfilter/mqfilter.cc
@@ -249,6 +249,9 @@ static const MXS_ENUM_VALUE trigger_values[] =
     {NULL}
 };
 
+extern "C"
+{
+
 /**
  * The module entry point routine. It is this routine that
  * must populate the structure that is referred to as the
@@ -315,6 +318,8 @@ MXS_MODULE* MXS_CREATE_MODULE()
     return &info;
 }
 
+}
+
 /**
  * Internal function used to initialize the connection to
  * the RabbitMQ server. Also used to reconnect to the server
@@ -495,7 +500,7 @@ char** parse_optstr(const char* str, const char* tok, int* szstore)
         size++;
     }
 
-    char **arr = MXS_MALLOC(sizeof(char*) * size);
+    char **arr = static_cast<char**>(MXS_MALLOC(sizeof(char*) * size));
     MXS_ABORT_IF_NULL(arr);
 
     *szstore = size;
@@ -523,7 +528,7 @@ char** parse_optstr(const char* str, const char* tok, int* szstore)
 static MXS_FILTER *
 createInstance(const char *name, char **options, MXS_CONFIG_PARAMETER *params)
 {
-    MQ_INSTANCE *my_instance = MXS_CALLOC(1, sizeof(MQ_INSTANCE));
+    MQ_INSTANCE *my_instance = static_cast<MQ_INSTANCE*>(MXS_CALLOC(1, sizeof(MQ_INSTANCE)));
 
     if (my_instance)
     {
@@ -543,7 +548,8 @@ createInstance(const char *name, char **options, MXS_CONFIG_PARAMETER *params)
         my_instance->rconn_intv = 1;
 
         my_instance->port = config_get_integer(params, "port");
-        my_instance->trgtype = config_get_enum(params, "logging_trigger", trigger_values);
+        my_instance->trgtype =
+            static_cast<log_trigger_t>(config_get_enum(params, "logging_trigger", trigger_values));
         my_instance->log_all = config_get_bool(params, "logging_log_all");
         my_instance->strict_logging = config_get_bool(params, "logging_strict");
         my_instance->hostname = MXS_STRDUP_A(config_get_string(params, "hostname"));
@@ -773,7 +779,7 @@ bool sendMessage(void* data)
 void pushMessage(MQ_INSTANCE *instance, amqp_basic_properties_t* prop, char* msg)
 {
 
-    mqmessage* newmsg = MXS_CALLOC(1, sizeof(mqmessage));
+    mqmessage* newmsg = static_cast<mqmessage*>(MXS_CALLOC(1, sizeof(mqmessage)));
     if (newmsg)
     {
         newmsg->msg = msg;
@@ -823,7 +829,7 @@ newSession(MXS_FILTER *instance, MXS_SESSION *session)
 
     MQ_SESSION *my_session;
 
-    if ((my_session = MXS_CALLOC(1, sizeof(MQ_SESSION))) != NULL)
+    if ((my_session = static_cast<MQ_SESSION*>(MXS_CALLOC(1, sizeof(MQ_SESSION)))) != NULL)
     {
         my_session->was_query = false;
         my_session->uid = NULL;
@@ -945,16 +951,16 @@ routeQuery(MXS_FILTER *instance, MXS_FILTER_SESSION *session, GWBUF *queue)
     amqp_basic_properties_t *prop;
 
     /**The user is changing databases*/
-    if (*((char*) (queue->start + 4)) == 0x02)
+    if (*(static_cast<char*>(queue->start) + 4) == 0x02)
     {
         if (my_session->db)
         {
             MXS_FREE(my_session->db);
         }
         plen = pktlen(queue->start);
-        my_session->db = MXS_CALLOC(plen, sizeof(char));
+        my_session->db = static_cast<char*>(MXS_CALLOC(plen, sizeof(char)));
         MXS_ABORT_IF_NULL(my_session->db);
-        memcpy(my_session->db, queue->start + 5, plen - 1);
+        memcpy(my_session->db, static_cast<char*>(queue->start) + 5, plen - 1);
     }
 
     if (modutil_is_SQL(queue))
@@ -1167,7 +1173,7 @@ routeQuery(MXS_FILTER *instance, MXS_FILTER_SESSION *session, GWBUF *queue)
             if (my_session->uid == NULL)
             {
 
-                my_session->uid = MXS_CALLOC(33, sizeof(char));
+                my_session->uid = static_cast<char*>(MXS_CALLOC(33, sizeof(char)));
 
                 if (my_session->uid)
                 {
@@ -1179,8 +1185,8 @@ routeQuery(MXS_FILTER *instance, MXS_FILTER_SESSION *session, GWBUF *queue)
             {
 
                 my_session->was_query = true;
-
-                if ((prop = MXS_MALLOC(sizeof(amqp_basic_properties_t))))
+                prop = static_cast<amqp_basic_properties_t*>(MXS_MALLOC(sizeof(amqp_basic_properties_t)));
+                if (prop)
                 {
                     prop->_flags = AMQP_BASIC_CONTENT_TYPE_FLAG |
                                    AMQP_BASIC_DELIVERY_MODE_FLAG |
@@ -1207,7 +1213,7 @@ routeQuery(MXS_FILTER *instance, MXS_FILTER_SESSION *session, GWBUF *queue)
                 sprintf(t_buf, "%lu|", (unsigned long) time(NULL));
 
                 int qlen = strnlen(canon_q, length) + strnlen(t_buf, 128);
-                combined = MXS_MALLOC((qlen + 1) * sizeof(char));
+                combined = static_cast<char*>(MXS_MALLOC((qlen + 1) * sizeof(char)));
                 MXS_ABORT_IF_NULL(combined);
                 strcpy(combined, t_buf);
                 strncat(combined, canon_q, length);
@@ -1303,7 +1309,7 @@ unsigned int consume_leitoi(unsigned char** c)
 char* consume_lestr(unsigned char** c)
 {
     unsigned int slen = consume_leitoi(c);
-    char *str = MXS_CALLOC((slen + 1), sizeof(char));
+    char *str = static_cast<char*>(MXS_CALLOC((slen + 1), sizeof(char)));
     if (str)
     {
         memcpy(str, *c, slen);
@@ -1354,7 +1360,7 @@ static int clientReply(MXS_FILTER* instance, MXS_FILTER_SESSION *session, GWBUF
 
         if (pkt_len > 0)
         {
-            if ((prop = MXS_MALLOC(sizeof(amqp_basic_properties_t))))
+            if ((prop = static_cast<amqp_basic_properties_t*>(MXS_MALLOC(sizeof(amqp_basic_properties_t)))))
             {
                 prop->_flags = AMQP_BASIC_CONTENT_TYPE_FLAG |
                                AMQP_BASIC_DELIVERY_MODE_FLAG |
@@ -1366,7 +1372,7 @@ static int clientReply(MXS_FILTER* instance, MXS_FILTER_SESSION *session, GWBUF
                 prop->message_id = amqp_cstring_bytes("reply");
             }
 
-            combined = MXS_CALLOC(GWBUF_LENGTH(reply) + 256, sizeof(char));
+            combined = static_cast<char*>(MXS_CALLOC(GWBUF_LENGTH(reply) + 256, sizeof(char)));
             MXS_ABORT_IF_NULL(combined);
 
             memset(t_buf, 0, 128);
@@ -1412,7 +1418,7 @@ static int clientReply(MXS_FILTER* instance, MXS_FILTER_SESSION *session, GWBUF
             {
                 /**ERR packet*/
                 sprintf(combined + offset, "ERROR - message: %.*s",
-                        (int) (reply->end - ((void*) (reply->sbuf->data + 13))),
+                        (int) (static_cast<unsigned char*>(reply->end) - (reply->sbuf->data + 13)),
                         (char *) reply->sbuf->data + 13);
                 packet_ok = 1;
                 was_last = 1;
@@ -1435,7 +1441,7 @@ static int clientReply(MXS_FILTER* instance, MXS_FILTER_SESSION *session, GWBUF
                 char *tmp;
                 unsigned int col_cnt = consume_leitoi(&rset);
 
-                tmp = MXS_CALLOC(256, sizeof(char));
+                tmp = static_cast<char*>(MXS_CALLOC(256, sizeof(char)));
                 MXS_ABORT_IF_NULL(tmp);
                 sprintf(tmp, "Columns: %d", col_cnt);
                 memcpy(combined + offset, tmp, strnlen(tmp, 256));
diff --git a/server/modules/filter/regexfilter/CMakeLists.txt b/server/modules/filter/regexfilter/CMakeLists.txt
index bf148b590..a6fc514ec 100644
--- a/server/modules/filter/regexfilter/CMakeLists.txt
+++ b/server/modules/filter/regexfilter/CMakeLists.txt
@@ -1,4 +1,4 @@
-add_library(regexfilter SHARED regexfilter.c)
+add_library(regexfilter SHARED regexfilter.cc)
 target_link_libraries(regexfilter maxscale-common)
 add_dependencies(regexfilter pcre2)
 set_target_properties(regexfilter PROPERTIES VERSION "1.1.0")
diff --git a/server/modules/filter/regexfilter/regexfilter.c b/server/modules/filter/regexfilter/regexfilter.cc
similarity index 97%
rename from server/modules/filter/regexfilter/regexfilter.c
rename to server/modules/filter/regexfilter/regexfilter.cc
index 525b0e9d3..0e7f5649a 100644
--- a/server/modules/filter/regexfilter/regexfilter.c
+++ b/server/modules/filter/regexfilter/regexfilter.cc
@@ -82,7 +82,7 @@ typedef struct
     int active; /* Is filter active */
 } REGEX_SESSION;
 
-void log_match(REGEX_INSTANCE* inst, char* re, char* old, char* new);
+void log_match(REGEX_INSTANCE* inst, char* re, char* old, char* newsql);
 void log_nomatch(REGEX_INSTANCE* inst, char* re, char* old);
 
 static const MXS_ENUM_VALUE option_values[] =
@@ -92,6 +92,9 @@ static const MXS_ENUM_VALUE option_values[] =
     {NULL}
 };
 
+extern "C"
+{
+
 /**
  * The module entry point routine. It is this routine that
  * must populate the structure that is referred to as the
@@ -146,6 +149,8 @@ MXS_MODULE* MXS_CREATE_MODULE()
     return &info;
 }
 
+}
+
 /**
  * Free a regexfilter instance.
  * @param instance instance to free
@@ -185,7 +190,7 @@ void free_instance(REGEX_INSTANCE *instance)
 static MXS_FILTER *
 createInstance(const char *name, char **options, MXS_CONFIG_PARAMETER *params)
 {
-    REGEX_INSTANCE *my_instance = MXS_CALLOC(1, sizeof(REGEX_INSTANCE));
+    REGEX_INSTANCE *my_instance = static_cast<REGEX_INSTANCE*>(MXS_CALLOC(1, sizeof(REGEX_INSTANCE)));
 
     if (my_instance)
     {
@@ -256,7 +261,7 @@ newSession(MXS_FILTER *instance, MXS_SESSION *session)
     REGEX_SESSION *my_session;
     const char *remote, *user;
 
-    if ((my_session = MXS_CALLOC(1, sizeof(REGEX_SESSION))) != NULL)
+    if ((my_session = static_cast<REGEX_SESSION*>(MXS_CALLOC(1, sizeof(REGEX_SESSION)))) != NULL)
     {
         my_session->no_change = 0;
         my_session->replacements = 0;
@@ -467,7 +472,7 @@ regex_replace(const char *sql, pcre2_code *re, pcre2_match_data *match_data, con
     if (pcre2_match(re, (PCRE2_SPTR) sql, PCRE2_ZERO_TERMINATED, 0, 0, match_data, NULL) > 0)
     {
         result_size = strlen(sql) + strlen(replace);
-        result = MXS_MALLOC(result_size);
+        result = static_cast<char*>(MXS_MALLOC(result_size));
 
         size_t result_size_tmp = result_size;
         while (result &&
@@ -478,7 +483,7 @@ regex_replace(const char *sql, pcre2_code *re, pcre2_match_data *match_data, con
         {
             result_size_tmp = 1.5 * result_size;
             char *tmp;
-            if ((tmp = MXS_REALLOC(result, result_size_tmp)) == NULL)
+            if ((tmp = static_cast<char*>(MXS_REALLOC(result, result_size_tmp))) == NULL)
             {
                 MXS_FREE(result);
                 result = NULL;
@@ -498,16 +503,16 @@ regex_replace(const char *sql, pcre2_code *re, pcre2_match_data *match_data, con
  * @param old Old SQL statement
  * @param new New SQL statement
  */
-void log_match(REGEX_INSTANCE* inst, char* re, char* old, char* new)
+void log_match(REGEX_INSTANCE* inst, char* re, char* old, char* newsql)
 {
     if (inst->logfile)
     {
-        fprintf(inst->logfile, "Matched %s: [%s] -> [%s]\n", re, old, new);
+        fprintf(inst->logfile, "Matched %s: [%s] -> [%s]\n", re, old, newsql);
         fflush(inst->logfile);
     }
     if (inst->log_trace)
     {
-        MXS_INFO("Match %s: [%s] -> [%s]", re, old, new);
+        MXS_INFO("Match %s: [%s] -> [%s]", re, old, newsql);
     }
 }
 
diff --git a/server/modules/filter/topfilter/CMakeLists.txt b/server/modules/filter/topfilter/CMakeLists.txt
index 668937c8d..39900bd5e 100644
--- a/server/modules/filter/topfilter/CMakeLists.txt
+++ b/server/modules/filter/topfilter/CMakeLists.txt
@@ -1,4 +1,4 @@
-add_library(topfilter SHARED topfilter.c)
+add_library(topfilter SHARED topfilter.cc)
 target_link_libraries(topfilter maxscale-common)
 set_target_properties(topfilter PROPERTIES VERSION "1.0.1")
 install_module(topfilter core)
diff --git a/server/modules/filter/topfilter/topfilter.c b/server/modules/filter/topfilter/topfilter.cc
similarity index 99%
rename from server/modules/filter/topfilter/topfilter.c
rename to server/modules/filter/topfilter/topfilter.cc
index c0e8fd8f8..b8df0ae10 100644
--- a/server/modules/filter/topfilter/topfilter.c
+++ b/server/modules/filter/topfilter/topfilter.cc
@@ -126,6 +126,9 @@ static const MXS_ENUM_VALUE option_values[] =
     {NULL}
 };
 
+extern "C"
+{
+
 /**
  * The module entry point routine. It is this routine that
  * must populate the structure that is referred to as the
@@ -185,6 +188,9 @@ MXS_MODULE* MXS_CREATE_MODULE()
 
     return &info;
 }
+
+}
+
 /**
  * Create an instance of the filter for a particular service
  * within MaxScale.
@@ -276,7 +282,7 @@ newSession(MXS_FILTER *instance, MXS_SESSION *session)
     int i;
     const char *remote, *user;
 
-    if ((my_session = MXS_CALLOC(1, sizeof(TOPN_SESSION))) != NULL)
+    if ((my_session = static_cast<TOPN_SESSION*>(MXS_CALLOC(1, sizeof(TOPN_SESSION)))) != NULL)
     {
         if ((my_session->filename =
                  (char *) MXS_MALLOC(strlen(my_instance->filebase) + 20))
diff --git a/server/modules/filter/tpmfilter/CMakeLists.txt b/server/modules/filter/tpmfilter/CMakeLists.txt
index 6a737b10b..5ac7490ff 100644
--- a/server/modules/filter/tpmfilter/CMakeLists.txt
+++ b/server/modules/filter/tpmfilter/CMakeLists.txt
@@ -1,4 +1,4 @@
-add_library(tpmfilter SHARED tpmfilter.c)
+add_library(tpmfilter SHARED tpmfilter.cc)
 target_link_libraries(tpmfilter maxscale-common)
 set_target_properties(tpmfilter PROPERTIES VERSION "1.0.0")
 install_module(tpmfilter experimental)
diff --git a/server/modules/filter/tpmfilter/tpmfilter.c b/server/modules/filter/tpmfilter/tpmfilter.cc
similarity index 98%
rename from server/modules/filter/tpmfilter/tpmfilter.c
rename to server/modules/filter/tpmfilter/tpmfilter.cc
index 5bfa61113..ebfc908c9 100644
--- a/server/modules/filter/tpmfilter/tpmfilter.c
+++ b/server/modules/filter/tpmfilter/tpmfilter.cc
@@ -67,7 +67,7 @@
 /* The maximum size for query statements in a transaction (64MB) */
 static size_t sql_size_limit = 64 * 1024 * 1024;
 /* The size of the buffer for recording latency of individual statements */
-static size_t latency_buf_size = 64 * 1024;
+static int latency_buf_size = 64 * 1024;
 static const int default_sql_size = 4 * 1024;
 
 #define DEFAULT_QUERY_DELIMITER "@@@"
@@ -140,6 +140,9 @@ typedef struct
     size_t      max_sql_size;
 } TPM_SESSION;
 
+extern "C"
+{
+
 /**
  * The module entry point routine. It is this routine that
  * must populate the structure that is referred to as the
@@ -193,6 +196,8 @@ MXS_MODULE* MXS_CREATE_MODULE()
     return &info;
 }
 
+}
+
 /**
  * Create an instance of the filter for a particular service
  * within MaxScale.
@@ -205,7 +210,7 @@ MXS_MODULE* MXS_CREATE_MODULE()
 static MXS_FILTER *
 createInstance(const char *name, char **options, MXS_CONFIG_PARAMETER *params)
 {
-    TPM_INSTANCE *my_instance = MXS_CALLOC(1, sizeof(TPM_INSTANCE));
+    TPM_INSTANCE *my_instance = static_cast<TPM_INSTANCE*>(MXS_CALLOC(1, sizeof(TPM_INSTANCE)));
 
     if (my_instance)
     {
@@ -310,7 +315,7 @@ newSession(MXS_FILTER *instance, MXS_SESSION *session)
     int     i;
     const char *remote, *user;
 
-    if ((my_session = MXS_CALLOC(1, sizeof(TPM_SESSION))) != NULL)
+    if ((my_session = static_cast<TPM_SESSION*>(MXS_CALLOC(1, sizeof(TPM_SESSION)))) != NULL)
     {
         atomic_add(&my_instance->sessions, 1);