diff --git a/programs/test/metatest.c b/programs/test/metatest.c
index 75829ec..9d90d8c 100644
--- a/programs/test/metatest.c
+++ b/programs/test/metatest.c
@@ -76,13 +76,13 @@
 /* Test framework features */
 /****************************************************************/
 
-void meta_test_fail(const char *name)
+static void meta_test_fail(const char *name)
 {
     (void) name;
     mbedtls_test_fail("Forced test failure", __LINE__, __FILE__);
 }
 
-void meta_test_not_equal(const char *name)
+static void meta_test_not_equal(const char *name)
 {
     int left = 20;
     int right = 10;
@@ -94,7 +94,7 @@
     ;
 }
 
-void meta_test_not_le_s(const char *name)
+static void meta_test_not_le_s(const char *name)
 {
     int left = 20;
     int right = 10;
@@ -106,7 +106,7 @@
     ;
 }
 
-void meta_test_not_le_u(const char *name)
+static void meta_test_not_le_u(const char *name)
 {
     size_t left = 20;
     size_t right = 10;
@@ -122,7 +122,7 @@
 /* Platform features */
 /****************************************************************/
 
-void null_pointer_dereference(const char *name)
+static void null_pointer_dereference(const char *name)
 {
     (void) name;
     volatile char *volatile p;
@@ -131,7 +131,7 @@
     mbedtls_printf("%p -> %u\n", p, (unsigned) *p);
 }
 
-void null_pointer_call(const char *name)
+static void null_pointer_call(const char *name)
 {
     (void) name;
     unsigned(*volatile p)(void);
@@ -148,7 +148,7 @@
 /* Memory */
 /****************************************************************/
 
-void read_after_free(const char *name)
+static void read_after_free(const char *name)
 {
     (void) name;
     volatile char *p = calloc_but_the_compiler_does_not_know(1, 1);
@@ -158,7 +158,7 @@
     mbedtls_printf("%u\n", (unsigned) *p);
 }
 
-void double_free(const char *name)
+static void double_free(const char *name)
 {
     (void) name;
     volatile char *p = calloc_but_the_compiler_does_not_know(1, 1);
@@ -168,7 +168,7 @@
     free_but_the_compiler_does_not_know((void *) p);
 }
 
-void read_uninitialized_stack(const char *name)
+static void read_uninitialized_stack(const char *name)
 {
     (void) name;
     char buf[1];
@@ -182,7 +182,7 @@
     }
 }
 
-void memory_leak(const char *name)
+static void memory_leak(const char *name)
 {
     (void) name;
     volatile char *p = calloc_but_the_compiler_does_not_know(1, 1);
@@ -196,7 +196,7 @@
  * %(start), %(offset) and %(count) are decimal integers.
  * %(direction) is either the character 'r' for read or 'w' for write.
  */
-void test_memory_poison(const char *name)
+static void test_memory_poison(const char *name)
 {
     size_t start = 0, offset = 0, count = 0;
     char direction = 'r';
@@ -254,7 +254,7 @@
 /* Threading */
 /****************************************************************/
 
-void mutex_lock_not_initialized(const char *name)
+static void mutex_lock_not_initialized(const char *name)
 {
     (void) name;
 #if defined(MBEDTLS_THREADING_C)
@@ -270,7 +270,7 @@
 #endif
 }
 
-void mutex_unlock_not_initialized(const char *name)
+static void mutex_unlock_not_initialized(const char *name)
 {
     (void) name;
 #if defined(MBEDTLS_THREADING_C)
@@ -286,7 +286,7 @@
 #endif
 }
 
-void mutex_free_not_initialized(const char *name)
+static void mutex_free_not_initialized(const char *name)
 {
     (void) name;
 #if defined(MBEDTLS_THREADING_C)
@@ -300,7 +300,7 @@
 #endif
 }
 
-void mutex_double_init(const char *name)
+static void mutex_double_init(const char *name)
 {
     (void) name;
 #if defined(MBEDTLS_THREADING_C)
@@ -315,7 +315,7 @@
 #endif
 }
 
-void mutex_double_free(const char *name)
+static void mutex_double_free(const char *name)
 {
     (void) name;
 #if defined(MBEDTLS_THREADING_C)
@@ -330,7 +330,7 @@
 #endif
 }
 
-void mutex_leak(const char *name)
+static void mutex_leak(const char *name)
 {
     (void) name;
 #if defined(MBEDTLS_THREADING_C)
diff --git a/programs/test/selftest.c b/programs/test/selftest.c
index 043209b..e72386f 100644
--- a/programs/test/selftest.c
+++ b/programs/test/selftest.c
@@ -241,7 +241,7 @@
 }
 #endif
 
-int mbedtls_entropy_self_test_wrapper(int verbose)
+static int mbedtls_entropy_self_test_wrapper(int verbose)
 {
 #if defined(MBEDTLS_ENTROPY_NV_SEED) && !defined(MBEDTLS_NO_PLATFORM_ENTROPY)
     create_entropy_seed_file();
@@ -252,7 +252,7 @@
 
 #if defined(MBEDTLS_SELF_TEST)
 #if defined(MBEDTLS_MEMORY_BUFFER_ALLOC_C)
-int mbedtls_memory_buffer_alloc_free_and_self_test(int verbose)
+static int mbedtls_memory_buffer_alloc_free_and_self_test(int verbose)
 {
     if (verbose != 0) {
 #if defined(MBEDTLS_MEMORY_DEBUG)
diff --git a/programs/test/udp_proxy.c b/programs/test/udp_proxy.c
index beaa8bd..bf06871 100644
--- a/programs/test/udp_proxy.c
+++ b/programs/test/udp_proxy.c
@@ -483,7 +483,7 @@
 } packet;
 
 /* Print packet. Outgoing packets come with a reason (forward, dupl, etc.) */
-void print_packet(const packet *p, const char *why)
+static void print_packet(const packet *p, const char *why)
 {
 #if defined(MBEDTLS_TIMING_C)
     if (why == NULL) {
@@ -527,7 +527,7 @@
 static inject_clihlo_state_t inject_clihlo_state;
 static packet initial_clihlo;
 
-int send_packet(const packet *p, const char *why)
+static int send_packet(const packet *p, const char *why)
 {
     int ret;
     mbedtls_net_context *dst = p->dst;
@@ -616,13 +616,13 @@
 static size_t prev_len;
 static packet prev[MAX_DELAYED_MSG];
 
-void clear_pending(void)
+static void clear_pending(void)
 {
     memset(&prev, 0, sizeof(prev));
     prev_len = 0;
 }
 
-void delay_packet(packet *delay)
+static void delay_packet(packet *delay)
 {
     if (prev_len == MAX_DELAYED_MSG) {
         return;
@@ -631,7 +631,7 @@
     memcpy(&prev[prev_len++], delay, sizeof(packet));
 }
 
-int send_delayed(void)
+static int send_delayed(void)
 {
     uint8_t offset;
     int ret;
@@ -663,7 +663,7 @@
 static unsigned char held[2048] = { 0 };
 #define HOLD_MAX 2
 
-int handle_message(const char *way,
+static int handle_message(const char *way,
                    mbedtls_net_context *dst,
                    mbedtls_net_context *src)
 {
diff --git a/programs/test/zeroize.c b/programs/test/zeroize.c
index 1e9b98d..c1cee0d 100644
--- a/programs/test/zeroize.c
+++ b/programs/test/zeroize.c
@@ -23,7 +23,7 @@
 
 #define BUFFER_LEN 1024
 
-void usage(void)
+static void usage(void)
 {
     mbedtls_printf("Zeroize is a simple program to assist with testing\n");
     mbedtls_printf("the mbedtls_platform_zeroize() function by using the\n");