diff --git a/tests/lwip_sock_udp/main.c b/tests/lwip_sock_udp/main.c
index 3c77e160c9675b3ce8b64f9697300e6353ba138d..3db379c3f7d606e6ad46bd9461f55e8b4c5f8688 100644
--- a/tests/lwip_sock_udp/main.c
+++ b/tests/lwip_sock_udp/main.c
@@ -85,10 +85,10 @@ static void test_sock_udp_create4__EINVAL_netif(void)
     static const sock_udp_ep_t local = { .family = AF_INET, .netif = _TEST_NETIF,
                                          .port = _TEST_PORT_LOCAL };
     /* port may not be NULL according to doc */
-    const sock_udp_ep_t remote = { .family = AF_INET,
-                                   .netif = (_TEST_NETIF + 1),
-                                   .port = _TEST_PORT_REMOTE,
-                                   .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE } };
+    static const sock_udp_ep_t remote = { .family = AF_INET,
+                                          .netif = (_TEST_NETIF + 1),
+                                          .port = _TEST_PORT_REMOTE,
+                                          .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE } };
 
     assert(-EINVAL == sock_udp_create(&_sock, &local, &remote, SOCK_FLAGS_REUSE_EP));
 }
@@ -157,9 +157,9 @@ static void test_sock_udp_create4__only_local_reuse_ep(void)
 
 static void test_sock_udp_create4__only_remote(void)
 {
-    const sock_udp_ep_t remote = { .family = AF_INET,
-                                   .port = _TEST_PORT_REMOTE,
-                                   .addr =  { .ipv4_u32 = _TEST_ADDR4_REMOTE } };
+    static const sock_udp_ep_t remote = { .family = AF_INET,
+                                          .port = _TEST_PORT_REMOTE,
+                                          .addr =  { .ipv4_u32 = _TEST_ADDR4_REMOTE } };
     sock_udp_ep_t ep;
 
     assert(0 == sock_udp_create(&_sock, NULL, &remote, SOCK_FLAGS_REUSE_EP));
@@ -176,9 +176,9 @@ static void test_sock_udp_create4__full(void)
 {
     static const sock_udp_ep_t local = { .family = AF_INET, .netif = _TEST_NETIF,
                                          .port = _TEST_PORT_LOCAL };
-    const sock_udp_ep_t remote = { .family = AF_INET,
-                                   .port = _TEST_PORT_REMOTE,
-                                   .addr =  { .ipv4_u32 = _TEST_ADDR4_REMOTE } };
+    static const sock_udp_ep_t remote = { .family = AF_INET,
+                                          .port = _TEST_PORT_REMOTE,
+                                          .addr =  { .ipv4_u32 = _TEST_ADDR4_REMOTE } };
     sock_udp_ep_t ep;
 
     assert(0 == sock_udp_create(&_sock, &local, &remote, SOCK_FLAGS_REUSE_EP));
@@ -246,9 +246,9 @@ static void test_sock_udp_recv4__socketed(void)
 {
     static const sock_udp_ep_t local = { .family = AF_INET,
                                          .port = _TEST_PORT_LOCAL };
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
-                                   .family = AF_INET,
-                                   .port = _TEST_PORT_REMOTE };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
+                                          .family = AF_INET,
+                                          .port = _TEST_PORT_REMOTE };
 
     assert(0 == sock_udp_create(&_sock, &local, &remote, SOCK_FLAGS_REUSE_EP));
     assert(_inject_4packet(_TEST_ADDR4_REMOTE, _TEST_ADDR4_LOCAL, _TEST_PORT_REMOTE,
@@ -264,9 +264,9 @@ static void test_sock_udp_recv4__socketed_with_remote(void)
 {
     static const sock_udp_ep_t local = { .family = AF_INET,
                                          .port = _TEST_PORT_LOCAL };
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
-                                   .family = AF_INET,
-                                   .port = _TEST_PORT_REMOTE };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
+                                          .family = AF_INET,
+                                          .port = _TEST_PORT_REMOTE };
     sock_udp_ep_t result;
 
     assert(0 == sock_udp_create(&_sock, &local, &remote, SOCK_FLAGS_REUSE_EP));
@@ -287,9 +287,9 @@ static void test_sock_udp_recv4__socketed_with_remote(void)
 
 static void test_sock_udp_recv4__unsocketed(void)
 {
-    const sock_udp_ep_t local = { .addr = { .ipv4_u32 = _TEST_ADDR4_LOCAL },
-                                  .family = AF_INET,
-                                  .port = _TEST_PORT_LOCAL };
+    static const sock_udp_ep_t local = { .addr = { .ipv4_u32 = _TEST_ADDR4_LOCAL },
+                                         .family = AF_INET,
+                                         .port = _TEST_PORT_LOCAL };
 
     assert(0 == sock_udp_create(&_sock, &local, NULL, SOCK_FLAGS_REUSE_EP));
     assert(_inject_4packet(_TEST_ADDR4_REMOTE, _TEST_ADDR4_LOCAL, _TEST_PORT_REMOTE,
@@ -368,9 +368,9 @@ static void test_sock_udp_recv4__non_blocking(void)
 
 static void test_sock_udp_send4__EAFNOSUPPORT(void)
 {
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
-                                   .family = AF_UNSPEC,
-                                   .port = _TEST_PORT_REMOTE };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
+                                          .family = AF_UNSPEC,
+                                          .port = _TEST_PORT_REMOTE };
 
     assert(-EAFNOSUPPORT == sock_udp_send(NULL, "ABCD", sizeof("ABCD"),
                                           &remote));
@@ -379,10 +379,10 @@ static void test_sock_udp_send4__EAFNOSUPPORT(void)
 
 static void test_sock_udp_send4__EINVAL_addr(void)
 {
-    const sock_udp_ep_t local = { .addr = { .ipv4_u32 = _TEST_ADDR4_LOCAL },
-                                  .family = AF_INET,
-                                  .port = _TEST_PORT_REMOTE,
-                                  .netif = _TEST_NETIF };
+    static const sock_udp_ep_t local = { .addr = { .ipv4_u32 = _TEST_ADDR4_LOCAL },
+                                         .family = AF_INET,
+                                         .port = _TEST_PORT_REMOTE,
+                                         .netif = _TEST_NETIF };
     static const sock_udp_ep_t remote = { .family = AF_INET,
                                           .port = _TEST_PORT_REMOTE,
                                           .netif = _TEST_NETIF };
@@ -394,14 +394,14 @@ static void test_sock_udp_send4__EINVAL_addr(void)
 
 static void test_sock_udp_send4__EINVAL_netif(void)
 {
-    const sock_udp_ep_t local = { .addr = { .ipv4_u32 = _TEST_ADDR4_LOCAL },
-                                  .family = AF_INET,
-                                  .port = _TEST_PORT_REMOTE,
-                                  .netif = _TEST_NETIF };
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
-                                   .family = AF_INET,
-                                   .port = _TEST_PORT_REMOTE,
-                                   .netif = _TEST_NETIF + 1 };
+    static const sock_udp_ep_t local = { .addr = { .ipv4_u32 = _TEST_ADDR4_LOCAL },
+                                         .family = AF_INET,
+                                         .port = _TEST_PORT_REMOTE,
+                                         .netif = _TEST_NETIF };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
+                                          .family = AF_INET,
+                                          .port = _TEST_PORT_REMOTE,
+                                          .netif = _TEST_NETIF + 1 };
 
     assert(0 == sock_udp_create(&_sock, &local, NULL, SOCK_FLAGS_REUSE_EP));
     assert(-EINVAL == sock_udp_send(&_sock, "ABCD", sizeof("ABCD"), &remote));
@@ -410,9 +410,9 @@ static void test_sock_udp_send4__EINVAL_netif(void)
 
 static void test_sock_udp_send4__EHOSTUNREACH(void)
 {
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_WRONG },
-                                   .family = AF_INET,
-                                   .port = _TEST_PORT_REMOTE };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_WRONG },
+                                          .family = AF_INET,
+                                          .port = _TEST_PORT_REMOTE };
 
     assert(-EHOSTUNREACH == sock_udp_send(NULL, "ABCD", sizeof("ABCD"),
                                           &remote));
@@ -420,8 +420,8 @@ static void test_sock_udp_send4__EHOSTUNREACH(void)
 
 static void test_sock_udp_send4__EINVAL_port(void)
 {
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
-                                   .family = AF_INET };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
+                                          .family = AF_INET };
 
     assert(-EINVAL == sock_udp_send(NULL, "ABCD", sizeof("ABCD"), &remote));
     assert(_check_net());
@@ -436,9 +436,9 @@ static void test_sock_udp_send4__ENOTCONN(void)
 
 static void test_sock_udp_send4__socketed_no_local_no_netif(void)
 {
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
-                                   .family = AF_INET,
-                                   .port = _TEST_PORT_REMOTE };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
+                                          .family = AF_INET,
+                                          .port = _TEST_PORT_REMOTE };
 
     assert(0 == sock_udp_create(&_sock, NULL, &remote, SOCK_FLAGS_REUSE_EP));
     assert(sizeof("ABCD") == sock_udp_send(&_sock, "ABCD", sizeof("ABCD"),
@@ -451,12 +451,12 @@ static void test_sock_udp_send4__socketed_no_local_no_netif(void)
 
 static void test_sock_udp_send4__socketed_no_netif(void)
 {
-    const sock_udp_ep_t local = { .addr = { .ipv4_u32 = _TEST_ADDR4_LOCAL },
-                                  .family = AF_INET,
-                                  .port = _TEST_PORT_LOCAL };
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
-                                   .family = AF_INET,
-                                   .port = _TEST_PORT_REMOTE };
+    static const sock_udp_ep_t local = { .addr = { .ipv4_u32 = _TEST_ADDR4_LOCAL },
+                                         .family = AF_INET,
+                                         .port = _TEST_PORT_LOCAL };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
+                                          .family = AF_INET,
+                                          .port = _TEST_PORT_REMOTE };
 
     assert(0 == sock_udp_create(&_sock, &local, &remote, SOCK_FLAGS_REUSE_EP));
     assert(sizeof("ABCD") == sock_udp_send(&_sock, "ABCD", sizeof("ABCD"),
@@ -470,10 +470,10 @@ static void test_sock_udp_send4__socketed_no_netif(void)
 
 static void test_sock_udp_send4__socketed_no_local(void)
 {
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
-                                   .family = AF_INET,
-                                   .netif = _TEST_NETIF,
-                                   .port = _TEST_PORT_REMOTE };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
+                                          .family = AF_INET,
+                                          .netif = _TEST_NETIF,
+                                          .port = _TEST_PORT_REMOTE };
 
     assert(0 == sock_udp_create(&_sock, NULL, &remote, SOCK_FLAGS_REUSE_EP));
     assert(sizeof("ABCD") == sock_udp_send(&_sock, "ABCD", sizeof("ABCD"),
@@ -487,13 +487,13 @@ static void test_sock_udp_send4__socketed_no_local(void)
 
 static void test_sock_udp_send4__socketed(void)
 {
-    const sock_udp_ep_t local = { .addr = { .ipv4_u32 = _TEST_ADDR4_LOCAL },
-                                  .family = AF_INET,
-                                  .netif = _TEST_NETIF,
-                                  .port = _TEST_PORT_LOCAL };
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
-                                   .family = AF_INET,
-                                   .port = _TEST_PORT_REMOTE };
+    static const sock_udp_ep_t local = { .addr = { .ipv4_u32 = _TEST_ADDR4_LOCAL },
+                                         .family = AF_INET,
+                                         .netif = _TEST_NETIF,
+                                         .port = _TEST_PORT_LOCAL };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
+                                          .family = AF_INET,
+                                          .port = _TEST_PORT_REMOTE };
 
     assert(0 == sock_udp_create(&_sock, &local, &remote, SOCK_FLAGS_REUSE_EP));
     assert(sizeof("ABCD") == sock_udp_send(&_sock, "ABCD", sizeof("ABCD"),
@@ -507,16 +507,16 @@ static void test_sock_udp_send4__socketed(void)
 
 static void test_sock_udp_send4__socketed_other_remote(void)
 {
-    const sock_udp_ep_t local = { .addr = { .ipv4_u32 = _TEST_ADDR4_LOCAL },
-                                  .family = AF_INET,
-                                  .netif = _TEST_NETIF,
-                                  .port = _TEST_PORT_LOCAL };
-    const sock_udp_ep_t sock_remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_WRONG },
-                                        .family = AF_INET,
-                                        .port = _TEST_PORT_REMOTE + _TEST_PORT_LOCAL };
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
-                                   .family = AF_INET,
-                                   .port = _TEST_PORT_REMOTE };
+    static const sock_udp_ep_t local = { .addr = { .ipv4_u32 = _TEST_ADDR4_LOCAL },
+                                         .family = AF_INET,
+                                         .netif = _TEST_NETIF,
+                                         .port = _TEST_PORT_LOCAL };
+    static const sock_udp_ep_t sock_remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_WRONG },
+                                               .family = AF_INET,
+                                               .port = _TEST_PORT_REMOTE + _TEST_PORT_LOCAL };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
+                                          .family = AF_INET,
+                                          .port = _TEST_PORT_REMOTE };
 
     assert(0 == sock_udp_create(&_sock, &local, &sock_remote, SOCK_FLAGS_REUSE_EP));
     assert(sizeof("ABCD") == sock_udp_send(&_sock, "ABCD", sizeof("ABCD"),
@@ -530,9 +530,9 @@ static void test_sock_udp_send4__socketed_other_remote(void)
 
 static void test_sock_udp_send4__unsocketed_no_local_no_netif(void)
 {
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
-                                   .family = AF_INET,
-                                   .port = _TEST_PORT_REMOTE };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
+                                          .family = AF_INET,
+                                          .port = _TEST_PORT_REMOTE };
 
     assert(0 == sock_udp_create(&_sock, NULL, NULL, SOCK_FLAGS_REUSE_EP));
     assert(sizeof("ABCD") == sock_udp_send(&_sock, "ABCD", sizeof("ABCD"),
@@ -546,12 +546,12 @@ static void test_sock_udp_send4__unsocketed_no_local_no_netif(void)
 
 static void test_sock_udp_send4__unsocketed_no_netif(void)
 {
-    const sock_udp_ep_t local = { .addr = { .ipv4_u32 = _TEST_ADDR4_LOCAL },
-                                  .family = AF_INET,
-                                  .port = _TEST_PORT_LOCAL };
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
-                                   .family = AF_INET,
-                                   .port = _TEST_PORT_REMOTE };
+    static const sock_udp_ep_t local = { .addr = { .ipv4_u32 = _TEST_ADDR4_LOCAL },
+                                         .family = AF_INET,
+                                         .port = _TEST_PORT_LOCAL };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
+                                          .family = AF_INET,
+                                          .port = _TEST_PORT_REMOTE };
 
     assert(0 == sock_udp_create(&_sock, &local, NULL, SOCK_FLAGS_REUSE_EP));
     assert(sizeof("ABCD") == sock_udp_send(&_sock, "ABCD", sizeof("ABCD"),
@@ -565,10 +565,10 @@ static void test_sock_udp_send4__unsocketed_no_netif(void)
 
 static void test_sock_udp_send4__unsocketed_no_local(void)
 {
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
-                                   .family = AF_INET,
-                                   .netif = _TEST_NETIF,
-                                   .port = _TEST_PORT_REMOTE };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
+                                          .family = AF_INET,
+                                          .netif = _TEST_NETIF,
+                                          .port = _TEST_PORT_REMOTE };
 
     assert(0 == sock_udp_create(&_sock, NULL, NULL, SOCK_FLAGS_REUSE_EP));
     assert(sizeof("ABCD") == sock_udp_send(&_sock, "ABCD", sizeof("ABCD"),
@@ -582,13 +582,13 @@ static void test_sock_udp_send4__unsocketed_no_local(void)
 
 static void test_sock_udp_send4__unsocketed(void)
 {
-    const sock_udp_ep_t local = { .addr = { .ipv4_u32 = _TEST_ADDR4_LOCAL },
-                                  .family = AF_INET,
-                                  .netif = _TEST_NETIF,
-                                  .port = _TEST_PORT_LOCAL };
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
-                                   .family = AF_INET,
-                                   .port = _TEST_PORT_REMOTE };
+    static const sock_udp_ep_t local = { .addr = { .ipv4_u32 = _TEST_ADDR4_LOCAL },
+                                         .family = AF_INET,
+                                         .netif = _TEST_NETIF,
+                                         .port = _TEST_PORT_LOCAL };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
+                                          .family = AF_INET,
+                                          .port = _TEST_PORT_REMOTE };
 
     assert(0 == sock_udp_create(&_sock, &local, NULL, SOCK_FLAGS_REUSE_EP));
     assert(sizeof("ABCD") == sock_udp_send(&_sock, "ABCD", sizeof("ABCD"),
@@ -602,9 +602,9 @@ static void test_sock_udp_send4__unsocketed(void)
 
 static void test_sock_udp_send4__no_sock_no_netif(void)
 {
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
-                                   .family = AF_INET,
-                                   .port = _TEST_PORT_REMOTE };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
+                                          .family = AF_INET,
+                                          .port = _TEST_PORT_REMOTE };
 
     assert(sizeof("ABCD") == sock_udp_send(NULL, "ABCD", sizeof("ABCD"),
                                            &remote));
@@ -617,10 +617,10 @@ static void test_sock_udp_send4__no_sock_no_netif(void)
 
 static void test_sock_udp_send4__no_sock(void)
 {
-    const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
-                                   .family = AF_INET,
-                                   .netif = _TEST_NETIF,
-                                   .port = _TEST_PORT_REMOTE };
+    static const sock_udp_ep_t remote = { .addr = { .ipv4_u32 = _TEST_ADDR4_REMOTE },
+                                          .family = AF_INET,
+                                          .netif = _TEST_NETIF,
+                                          .port = _TEST_PORT_REMOTE };
 
     assert(sizeof("ABCD") == sock_udp_send(NULL, "ABCD", sizeof("ABCD"),
                                            &remote));