diff --git a/exec/apidef.c b/exec/apidef.c
index adb2c885..b22b17f1 100644
--- a/exec/apidef.c
+++ b/exec/apidef.c
@@ -86,7 +86,7 @@ typedef int (*typedef_tpg_groups_send_ok) (
 static inline void _corosync_public_exit_error (cs_fatal_error_t err,
 						const char *file,
 						unsigned int line)
-  __attribute__((__noreturn__));
+  __attribute__((noreturn));
 static inline void _corosync_public_exit_error (
 	cs_fatal_error_t err, const char *file, unsigned int line)
 {
diff --git a/exec/logsys.c b/exec/logsys.c
index 58c0b6e5..6d276c8f 100644
--- a/exec/logsys.c
+++ b/exec/logsys.c
@@ -729,7 +729,7 @@ static void log_printf_to_logs_wthread (
 	sem_post (&logsys_print_finished);
 }
 
-static void *logsys_worker_thread (void *data) __attribute__((__noreturn__));
+static void *logsys_worker_thread (void *data) __attribute__((noreturn));
 static void *logsys_worker_thread (void *data)
 {
 	struct record *rec;
diff --git a/exec/main.c b/exec/main.c
index f3b91fb0..cc035639 100644
--- a/exec/main.c
+++ b/exec/main.c
@@ -999,6 +999,8 @@ static void corosync_sending_allowed_release (void *sending_allowed_private_data
 static int ipc_subsys_id = -1;
 
 
+static void ipc_fatal_error(const char *error_msg) __attribute__((noreturn));
+
 static void ipc_fatal_error(const char *error_msg) {
        _logsys_log_printf (
 		LOGSYS_ENCODE_RECID(LOGSYS_LEVEL_ERROR,
diff --git a/exec/util.c b/exec/util.c
index b724cfcc..54152c30 100644
--- a/exec/util.c
+++ b/exec/util.c
@@ -81,12 +81,16 @@ cs_time_t clust_time_now(void)
 	return time_now;
 }
 
+void _corosync_out_of_memory_error (void) __attribute__((noreturn));
 void _corosync_out_of_memory_error (void)
 {
 	assert (0==1);
 	exit (EXIT_FAILURE);
 }
 
+void _corosync_exit_error (
+	enum e_ais_done err, const char *file, unsigned int line)  __attribute__((noreturn));
+
 void _corosync_exit_error (
 	enum e_ais_done err, const char *file, unsigned int line)
 {
diff --git a/exec/util.h b/exec/util.h
index ce820e82..7b955368 100644
--- a/exec/util.h
+++ b/exec/util.h
@@ -69,9 +69,8 @@ enum e_ais_done {
 extern int name_match(cs_name_t *name1, cs_name_t *name2);
 #define corosync_exit_error(err) _corosync_exit_error ((err), __FILE__, __LINE__)
 extern void _corosync_exit_error (enum e_ais_done err, const char *file,
-				  unsigned int line)
-  __attribute__((__noreturn__));
-void _corosync_out_of_memory_error (void) __attribute__((__noreturn__));
+				  unsigned int line) __attribute__((noreturn));
+void _corosync_out_of_memory_error (void) __attribute__((noreturn));
 extern char *getcs_name_t (cs_name_t *name);
 extern void setcs_name_t (cs_name_t *name, char *str);
 extern int cs_name_tisEqual (cs_name_t *str1, char *str2);
diff --git a/include/corosync/coroipcs.h b/include/corosync/coroipcs.h
index f08f0e5e..9f0dc1db 100644
--- a/include/corosync/coroipcs.h
+++ b/include/corosync/coroipcs.h
@@ -69,7 +69,7 @@ struct coroipcs_init_state {
 	void (*poll_dispatch_add)(int fd, void *context);
 	void (*poll_dispatch_modify)(int fd, int events);
 	void (*poll_dispatch_destroy)(int fd, void *context);
-	void (*fatal_error)(const char *error_msg);
+	void (*fatal_error)(const char *error_msg) __attribute__ ((noreturn));
 	coroipcs_init_fn_lvalue (*init_fn_get)(unsigned int service);
 	coroipcs_exit_fn_lvalue (*exit_fn_get)(unsigned int service);
 	coroipcs_handler_fn_lvalue (*handler_fn_get)(unsigned int service, unsigned int id);
@@ -96,7 +96,7 @@ struct coroipcs_init_state_v2 {
 	void (*poll_dispatch_add)(int fd, void *context);
 	void (*poll_dispatch_modify)(int fd, int events);
 	void (*poll_dispatch_destroy)(int fd, void *context);
-	void (*fatal_error)(const char *error_msg);
+	void (*fatal_error)(const char *error_msg) __attribute__ ((noreturn));
 	coroipcs_init_fn_lvalue (*init_fn_get)(unsigned int service);
 	coroipcs_exit_fn_lvalue (*exit_fn_get)(unsigned int service);
 	coroipcs_handler_fn_lvalue (*handler_fn_get)(unsigned int service, unsigned int id);
diff --git a/include/corosync/engine/coroapi.h b/include/corosync/engine/coroapi.h
index 7639ab1c..c3c812ff 100644
--- a/include/corosync/engine/coroapi.h
+++ b/include/corosync/engine/coroapi.h
@@ -591,9 +591,12 @@ struct corosync_api_v1 {
 	/*
 	 * Error handling APIs
 	 */
-	void (*error_memory_failure) (void);
+	void (*error_memory_failure) (void) __attribute__ ((noreturn));
+
 #define corosync_fatal_error(err) api->fatal_error ((err), __FILE__, __LINE__)
-	void (*fatal_error) (cs_fatal_error_t err, const char *file, unsigned int line);
+	void (*fatal_error) (cs_fatal_error_t err,
+		const char *file,
+		unsigned int line) __attribute__ ((noreturn));
 
 	void (*shutdown_request) (void);
 
diff --git a/test/testcpg.c b/test/testcpg.c
index 5b314d42..c8bfb3e8 100644
--- a/test/testcpg.c
+++ b/test/testcpg.c
@@ -159,7 +159,7 @@ static cpg_model_v1_data_t model_data = {
 	.flags =                     CPG_MODEL_V1_DELIVER_INITIAL_TOTEM_CONF,
 };
 
-static void sigintr_handler (int signum) __attribute__((__noreturn__));
+static void sigintr_handler (int signum) __attribute__((noreturn));
 static void sigintr_handler (int signum) {
 	exit (0);
 }
diff --git a/test/testcpgzc.c b/test/testcpgzc.c
index 4883b0e4..5b496a8f 100644
--- a/test/testcpgzc.c
+++ b/test/testcpgzc.c
@@ -151,7 +151,7 @@ static cpg_callbacks_t callbacks = {
 	.cpg_confchg_fn =            ConfchgCallback,
 };
 
-static void sigintr_handler (int signum) __attribute__((__noreturn__));
+static void sigintr_handler (int signum) __attribute__((noreturn));
 static void sigintr_handler (int signum) {
 	exit (0);
 }
diff --git a/test/testzcgc.c b/test/testzcgc.c
index 70841181..67714857 100644
--- a/test/testzcgc.c
+++ b/test/testzcgc.c
@@ -151,7 +151,7 @@ static cpg_callbacks_t callbacks = {
 	.cpg_confchg_fn =            ConfchgCallback,
 };
 
-static void sigintr_handler (int signum) __attribute__((__noreturn__));
+static void sigintr_handler (int signum) __attribute__((noreturn));
 static void sigintr_handler (int signum) {
 	exit (0);
 }