diff --git a/src/openvpn/comp-lz4.c b/src/openvpn/comp-lz4.c
index 6e40c325..e056caa8 100644
--- a/src/openvpn/comp-lz4.c
+++ b/src/openvpn/comp-lz4.c
@@ -185,7 +185,7 @@ lz4v2_compress(struct buffer *buf, struct buffer work,
     }
 }
 
-void
+static void
 do_lz4_decompress(size_t zlen_max,
                   struct buffer *work,
                   struct buffer *buf,
diff --git a/src/openvpn/forward.c b/src/openvpn/forward.c
index c45d1259..6cc59383 100644
--- a/src/openvpn/forward.c
+++ b/src/openvpn/forward.c
@@ -1007,7 +1007,7 @@ process_incoming_link_part2(struct context *c, struct link_socket_info *lsi, con
     }
 }
 
-void
+static void
 process_incoming_link(struct context *c)
 {
     perf_push(PERF_PROC_IN_LINK);
diff --git a/src/openvpn/manage.c b/src/openvpn/manage.c
index 3bbe972e..88121a38 100644
--- a/src/openvpn/manage.c
+++ b/src/openvpn/manage.c
@@ -3515,7 +3515,7 @@ management_query_user_pass(struct management *man,
 
 #ifdef MANAGMENT_EXTERNAL_KEY
 
-int
+static int
 management_query_multiline(struct management *man,
                            const char *b64_data, const char *prompt, const char *cmd, int *state, struct buffer_list **input)
 {
@@ -3591,7 +3591,7 @@ done:
     return ret;
 }
 
-char *
+static char *
 /* returns allocated base64 signature */
 management_query_multiline_flatten_newline(struct management *man,
                                            const char *b64_data, const char *prompt, const char *cmd, int *state, struct buffer_list **input)
@@ -3620,7 +3620,7 @@ management_query_multiline_flatten_newline(struct management *man,
     return result;
 }
 
-char *
+static char *
 /* returns allocated base64 signature */
 management_query_multiline_flatten(struct management *man,
                                    const char *b64_data, const char *prompt, const char *cmd, int *state, struct buffer_list **input)
diff --git a/src/openvpn/mtcp.c b/src/openvpn/mtcp.c
index 851643a9..3cb52113 100644
--- a/src/openvpn/mtcp.c
+++ b/src/openvpn/mtcp.c
@@ -521,7 +521,7 @@ multi_tcp_dispatch(struct multi_context *m, struct multi_instance *mi, const int
     return touched;
 }
 
-int
+static int
 multi_tcp_post(struct multi_context *m, struct multi_instance *mi, const int action)
 {
     struct context *c = multi_tcp_context(m, mi);
diff --git a/src/openvpn/multi.c b/src/openvpn/multi.c
index 7edfee1b..c798c438 100644
--- a/src/openvpn/multi.c
+++ b/src/openvpn/multi.c
@@ -485,7 +485,7 @@ multi_instance_string(const struct multi_instance *mi, bool null, struct gc_aren
     }
 }
 
-void
+static void
 generate_prefix(struct multi_instance *mi)
 {
     struct gc_arena gc = gc_new();
@@ -2967,7 +2967,7 @@ gremlin_flood_clients(struct multi_context *m)
 }
 #endif /* ifdef ENABLE_DEBUG */
 
-bool
+static bool
 stale_route_check_trigger(struct multi_context *m)
 {
     struct timeval null;
diff --git a/src/openvpn/ntlm.c b/src/openvpn/ntlm.c
index 65c1cbf5..167c10b8 100644
--- a/src/openvpn/ntlm.c
+++ b/src/openvpn/ntlm.c
@@ -131,7 +131,7 @@ gen_nonce(unsigned char *nonce)
     }
 }
 
-void
+static void
 my_strupr(char *str)
 {
     /* converts string to uppercase in place */
diff --git a/src/openvpn/options.c b/src/openvpn/options.c
index 1d5b62ca..c4bd8cba 100644
--- a/src/openvpn/options.c
+++ b/src/openvpn/options.c
@@ -959,7 +959,7 @@ pull_filter_type_name(int type)
 
 #endif
 
-void
+static void
 setenv_connection_entry(struct env_set *es,
                         const struct connection_entry *e,
                         const int i)
@@ -1439,7 +1439,7 @@ rol_check_alloc(struct options *options)
     }
 }
 
-void
+static void
 rol6_check_alloc(struct options *options)
 {
     if (!options->routes_ipv6)
@@ -1869,7 +1869,7 @@ parse_http_proxy_override(const char *server,
     }
 }
 
-void
+static void
 options_postprocess_http_proxy_override(struct options *o)
 {
     const struct connection_list *l = o->connection_list;
@@ -1986,7 +1986,7 @@ alloc_pull_filter(struct options *o, const int msglevel)
     return f;
 }
 
-void
+static void
 connection_entry_load_re(struct connection_entry *ce, const struct remote_entry *re)
 {
     if (re->remote)
diff --git a/src/openvpn/proxy.c b/src/openvpn/proxy.c
index 1ae93ad5..fdc73b4a 100644
--- a/src/openvpn/proxy.c
+++ b/src/openvpn/proxy.c
@@ -549,7 +549,7 @@ http_proxy_close(struct http_proxy_info *hp)
     free(hp);
 }
 
-bool
+static bool
 add_proxy_headers(struct http_proxy_info *p,
                   socket_descriptor_t sd, /* already open to proxy */
                   const char *host,       /* openvpn server remote */
diff --git a/src/openvpn/route.c b/src/openvpn/route.c
index a8a4c66d..1d8bb001 100644
--- a/src/openvpn/route.c
+++ b/src/openvpn/route.c
@@ -518,14 +518,14 @@ add_route_ipv6_to_option_list(struct route_ipv6_option_list *l,
     l->routes_ipv6 = ro;
 }
 
-void
+static void
 clear_route_list(struct route_list *rl)
 {
     gc_free(&rl->gc);
     CLEAR(*rl);
 }
 
-void
+static void
 clear_route_ipv6_list(struct route_ipv6_list *rl6)
 {
     gc_free(&rl6->gc);
diff --git a/src/openvpn/socket.c b/src/openvpn/socket.c
index 6e01fe10..3d4f881e 100644
--- a/src/openvpn/socket.c
+++ b/src/openvpn/socket.c
@@ -1431,7 +1431,7 @@ set_actual_address(struct link_socket_actual *actual, struct addrinfo *ai)
 
 }
 
-void
+static void
 socket_connect(socket_descriptor_t *sd,
                const struct sockaddr *dest,
                const int connect_timeout,
diff --git a/src/openvpn/ssl.c b/src/openvpn/ssl.c
index ff311d8e..4ccc50c0 100644
--- a/src/openvpn/ssl.c
+++ b/src/openvpn/ssl.c
@@ -1607,7 +1607,7 @@ key_source2_print(const struct key_source2 *k)
  * @param out           Output buffer
  * @param olen          Length of the output buffer
  */
-void
+static void
 tls1_P_hash(const md_kt_t *md_kt,
             const uint8_t *sec,
             int sec_len,