diff --git a/arch/cpu/arm/arm-def.h b/arch/cpu/arm/arm-def.h
index 63a70a535..2cd31604c 100644
--- a/arch/cpu/arm/arm-def.h
+++ b/arch/cpu/arm/arm-def.h
@@ -42,16 +42,6 @@
 /*---------------------------------------------------------------------------*/
 #include <stdint.h>
 /*---------------------------------------------------------------------------*/
-/**
- * \name Compiler configuration
- *
- * Those values are not meant to be modified by the user
- * @{
- */
-#define CCIF
-#define CLIF
-/** @} */
-/*---------------------------------------------------------------------------*/
 /**
  * \name Macros and typedefs
  *
diff --git a/arch/cpu/cc2538/clock.c b/arch/cpu/cc2538/clock.c
index 2842a3be8..839c72242 100644
--- a/arch/cpu/cc2538/clock.c
+++ b/arch/cpu/cc2538/clock.c
@@ -114,7 +114,7 @@ clock_init(void)
   REG(GPT_0_BASE + GPTIMER_TAPR) = PRESCALER_VALUE;
 }
 /*---------------------------------------------------------------------------*/
-CCIF clock_time_t
+clock_time_t
 clock_time(void)
 {
   return rt_ticks_startup / RTIMER_CLOCK_TICK_RATIO;
@@ -126,7 +126,7 @@ clock_set_seconds(unsigned long sec)
   rt_ticks_epoch = (uint64_t)sec * RTIMER_SECOND;
 }
 /*---------------------------------------------------------------------------*/
-CCIF unsigned long
+unsigned long
 clock_seconds(void)
 {
   return rt_ticks_epoch / RTIMER_SECOND;
diff --git a/arch/cpu/cc26xx-cc13xx/clock.c b/arch/cpu/cc26xx-cc13xx/clock.c
index 981bbb4b2..172d1c3fd 100644
--- a/arch/cpu/cc26xx-cc13xx/clock.c
+++ b/arch/cpu/cc26xx-cc13xx/clock.c
@@ -124,7 +124,7 @@ update_clock_variable(void)
   count = (aon_rtc_secs_now * CLOCK_SECOND) + (aon_rtc_ticks_now >> 9);
 }
 /*---------------------------------------------------------------------------*/
-CCIF clock_time_t
+clock_time_t
 clock_time(void)
 {
   update_clock_variable();
@@ -142,7 +142,7 @@ clock_update(void)
   }
 }
 /*---------------------------------------------------------------------------*/
-CCIF unsigned long
+unsigned long
 clock_seconds(void)
 {
   bool interrupts_disabled;
diff --git a/arch/cpu/msp430/msp430-def.h b/arch/cpu/msp430/msp430-def.h
index 2f14d7236..93e575702 100644
--- a/arch/cpu/msp430/msp430-def.h
+++ b/arch/cpu/msp430/msp430-def.h
@@ -79,9 +79,6 @@ typedef long off_t;
 /* Our clock resolution, this is the same as Unix HZ. */
 #define CLOCK_CONF_SECOND 128UL
 
-#define CCIF
-#define CLIF
-
 typedef int spl_t;
 spl_t   splhigh_(void);
 
diff --git a/arch/cpu/nrf52832/dev/clock.c b/arch/cpu/nrf52832/dev/clock.c
index 68413c23b..496668ecb 100644
--- a/arch/cpu/nrf52832/dev/clock.c
+++ b/arch/cpu/nrf52832/dev/clock.c
@@ -116,7 +116,7 @@ clock_init(void)
   rtc_config();
 }
 /*---------------------------------------------------------------------------*/
-CCIF clock_time_t
+clock_time_t
 clock_time(void)
 {
   return (clock_time_t)(ticks & 0xFFFFFFFF);
@@ -131,7 +131,7 @@ clock_update(void)
   }
 }
 /*---------------------------------------------------------------------------*/
-CCIF unsigned long
+unsigned long
 clock_seconds(void)
 {
   return (unsigned long)ticks/CLOCK_CONF_SECOND;
diff --git a/arch/platform/cooja/contiki-conf.h b/arch/platform/cooja/contiki-conf.h
index af7582ab9..4a8e17c64 100644
--- a/arch/platform/cooja/contiki-conf.h
+++ b/arch/platform/cooja/contiki-conf.h
@@ -98,9 +98,6 @@
 #define CC_CONF_VA_ARGS                1
 #define CC_CONF_INLINE inline
 
-#define CCIF
-#define CLIF
-
 /* These names are deprecated, use C99 names. */
 #include <inttypes.h>
 typedef uint8_t u8_t;
diff --git a/arch/platform/jn516x/jn516x-def.h b/arch/platform/jn516x/jn516x-def.h
index 4861d00b3..2526d2698 100644
--- a/arch/platform/jn516x/jn516x-def.h
+++ b/arch/platform/jn516x/jn516x-def.h
@@ -217,9 +217,6 @@ typedef uint32_t rtimer_clock_t;
 #define CC_CONF_VA_ARGS                1
 #define CC_CONF_INLINE                 inline
 
-#define CCIF
-#define CLIF
-
 #ifdef HAVE_STDINT_H
 #include <stdint.h>
 #else
diff --git a/arch/platform/native/contiki-conf.h b/arch/platform/native/contiki-conf.h
index 3a0329a82..eef8b0a83 100644
--- a/arch/platform/native/contiki-conf.h
+++ b/arch/platform/native/contiki-conf.h
@@ -58,9 +58,6 @@ int select_set_callback(int fd, const struct select_callback *callback);
 #define EEPROM_CONF_SIZE				1024
 #endif
 
-#define CCIF
-#define CLIF
-
 /* These names are deprecated, use C99 names. */
 typedef uint8_t   u8_t;
 typedef uint16_t u16_t;
diff --git a/arch/platform/native/platform.c b/arch/platform/native/platform.c
index 8f119acd9..fceab0207 100644
--- a/arch/platform/native/platform.c
+++ b/arch/platform/native/platform.c
@@ -111,7 +111,12 @@
 static const struct select_callback *select_callback[SELECT_MAX];
 static int select_max = 0;
 
-static uint8_t serial_id[] = {0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08};
+#ifdef PLATFORM_CONF_MAC_ADDR
+static uint8_t mac_addr[] = PLATFORM_CONF_MAC_ADDR;
+#else /* PLATFORM_CONF_MAC_ADDR */
+static uint8_t mac_addr[] = { 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08 };
+#endif /* PLATFORM_CONF_MAC_ADDR */
+
 #if !NETSTACK_CONF_WITH_IPV6
 static uint16_t node_id = 0x0102;
 #endif /* !NETSTACK_CONF_WITH_IPV6 */
@@ -177,12 +182,12 @@ set_lladdr(void)
 
   memset(&addr, 0, sizeof(linkaddr_t));
 #if NETSTACK_CONF_WITH_IPV6
-  memcpy(addr.u8, serial_id, sizeof(addr.u8));
+  memcpy(addr.u8, mac_addr, sizeof(addr.u8));
 #else
   if(node_id == 0) {
     int i;
     for(i = 0; i < sizeof(linkaddr_t); ++i) {
-      addr.u8[i] = serial_id[7 - i];
+      addr.u8[i] = mac_addr[7 - i];
     }
   } else {
     addr.u8[0] = node_id & 0xff;
diff --git a/os/net/ipv6/resolv.h b/os/net/ipv6/resolv.h
index ed24d5bce..ac414425f 100644
--- a/os/net/ipv6/resolv.h
+++ b/os/net/ipv6/resolv.h
@@ -55,7 +55,7 @@
 /**
  * Event that is broadcasted when a DNS name has been resolved.
  */
-CCIF extern process_event_t resolv_event_found;
+extern process_event_t resolv_event_found;
 
 enum {
   /** Hostname is fresh and usable. This response is cached and will eventually
@@ -91,14 +91,14 @@ enum {
 typedef uint8_t resolv_status_t;
 
 /* Functions. */
-CCIF resolv_status_t resolv_lookup(const char *name, uip_ipaddr_t ** ipaddr);
+resolv_status_t resolv_lookup(const char *name, uip_ipaddr_t ** ipaddr);
 
-CCIF void resolv_query(const char *name);
+void resolv_query(const char *name);
 
 #if RESOLV_CONF_SUPPORTS_MDNS
-CCIF void resolv_set_hostname(const char *hostname);
+void resolv_set_hostname(const char *hostname);
 
-CCIF const char *resolv_get_hostname(void);
+const char *resolv_get_hostname(void);
 #endif
 
 PROCESS_NAME(resolv_process);
diff --git a/os/net/ipv6/tcpip.h b/os/net/ipv6/tcpip.h
index bf8c9b0b1..8f84cedb3 100644
--- a/os/net/ipv6/tcpip.h
+++ b/os/net/ipv6/tcpip.h
@@ -108,8 +108,7 @@ void tcpip_uipcall(void);
  * process whenever an event occurs on the connection.
  *
  */
-CCIF void tcp_attach(struct uip_conn *conn,
-		     void *appstate);
+void tcp_attach(struct uip_conn *conn, void *appstate);
 #define tcp_markconn(conn, appstate) tcp_attach(conn, appstate)
 
 /**
@@ -126,7 +125,7 @@ CCIF void tcp_attach(struct uip_conn *conn,
  * \param port The port number in network byte order.
  *
  */
-CCIF void tcp_listen(uint16_t port);
+void tcp_listen(uint16_t port);
 
 /**
  * Close a listening TCP port.
@@ -140,7 +139,7 @@ CCIF void tcp_listen(uint16_t port);
  * \param port The port number in network byte order.
  *
  */
-CCIF void tcp_unlisten(uint16_t port);
+void tcp_unlisten(uint16_t port);
 
 /**
  * Open a TCP connection to the specified IP address and port.
@@ -165,8 +164,8 @@ CCIF void tcp_unlisten(uint16_t port);
  * memory could not be allocated for the connection.
  *
  */
-CCIF struct uip_conn *tcp_connect(const uip_ipaddr_t *ripaddr, uint16_t port,
-				  void *appstate);
+struct uip_conn *tcp_connect(const uip_ipaddr_t *ripaddr, uint16_t port,
+                             void *appstate);
 
 /**
  * Cause a specified TCP connection to be polled.
@@ -226,8 +225,8 @@ void udp_attach(struct uip_udp_conn *conn,
  * \return A pointer to the newly created connection, or NULL if
  * memory could not be allocated for the connection.
  */
-CCIF struct uip_udp_conn *udp_new(const uip_ipaddr_t *ripaddr, uint16_t port,
-				  void *appstate);
+struct uip_udp_conn *udp_new(const uip_ipaddr_t *ripaddr, uint16_t port,
+                             void *appstate);
 
 /**
  * Create a new UDP broadcast connection.
@@ -272,7 +271,7 @@ struct uip_udp_conn *udp_broadcast_new(uint16_t port, void *appstate);
  * \param conn A pointer to the UDP connection that should be polled.
  *
  */
-CCIF void tcpip_poll_udp(struct uip_udp_conn *conn);
+void tcpip_poll_udp(struct uip_udp_conn *conn);
 
 /** @} */
 
@@ -288,7 +287,7 @@ CCIF void tcpip_poll_udp(struct uip_udp_conn *conn);
  *
  * This event is posted to a process whenever a uIP ICMP event has occurred.
  */
-CCIF extern process_event_t tcpip_icmp6_event;
+extern process_event_t tcpip_icmp6_event;
 
 /**
  * \brief register an ICMPv6 callback
@@ -318,7 +317,7 @@ void tcpip_icmp6_call(uint8_t type);
  *
  * This event is posted to a process whenever a uIP event has occurred.
  */
-CCIF extern process_event_t tcpip_event;
+extern process_event_t tcpip_event;
 
 
 /**
@@ -335,7 +334,7 @@ CCIF extern process_event_t tcpip_event;
  *             and the length of the packet must be in the global
  *             uip_len variable.
  */
-CCIF void tcpip_input(void);
+void tcpip_input(void);
 
 /**
  * \brief Output packet to layer 2
diff --git a/os/net/ipv6/uip.h b/os/net/ipv6/uip.h
index c3c9f2b38..7751b8fc3 100755
--- a/os/net/ipv6/uip.h
+++ b/os/net/ipv6/uip.h
@@ -500,7 +500,7 @@ typedef union {
   uint8_t u8[UIP_BUFSIZE];
 } uip_buf_t;
 
-CCIF extern uip_buf_t uip_aligned_buf;
+extern uip_buf_t uip_aligned_buf;
 
 /** Macro to access uip_aligned_buf as an array of bytes */
 #define uip_buf (uip_aligned_buf.u8)
@@ -620,7 +620,7 @@ struct uip_conn *uip_connect(const uip_ipaddr_t *ripaddr, uint16_t port);
  *
  * \hideinitializer
  */
-CCIF void uip_send(const void *data, int len);
+void uip_send(const void *data, int len);
 
 /**
  * The length of any incoming data that is currently available (if available)
@@ -1238,14 +1238,14 @@ struct uip_udp_conn *uip_udp_new(const uip_ipaddr_t *ripaddr, uint16_t rport);
  * network byte order, use the UIP_HTONS() macro instead.
  */
 #ifndef uip_htons
-CCIF uint16_t uip_htons(uint16_t val);
+uint16_t uip_htons(uint16_t val);
 #endif /* uip_htons */
 #ifndef uip_ntohs
 #define uip_ntohs uip_htons
 #endif
 
 #ifndef uip_htonl
-CCIF uint32_t uip_htonl(uint32_t val);
+uint32_t uip_htonl(uint32_t val);
 #endif /* uip_htonl */
 #ifndef uip_ntohl
 #define uip_ntohl uip_htonl
@@ -1260,7 +1260,7 @@ CCIF uint32_t uip_htonl(uint32_t val);
  * called. If the application wishes to send data, the application may
  * use this space to write the data into before calling uip_send().
  */
-CCIF extern void *uip_appdata;
+extern void *uip_appdata;
 
 #if UIP_URGDATA > 0
 /* uint8_t *uip_urgdata:
@@ -1295,7 +1295,7 @@ extern void *uip_urgdata;
  * packet.
  *
  */
-CCIF extern uint16_t uip_len;
+extern uint16_t uip_len;
 
 /**
  * The length of the extension headers
@@ -1367,10 +1367,10 @@ struct uip_conn {
  * connection.
  */
 
-CCIF extern struct uip_conn *uip_conn;
+extern struct uip_conn *uip_conn;
 #if UIP_TCP
 /* The array containing all uIP connections. */
-CCIF extern struct uip_conn uip_conns[UIP_TCP_CONNS];
+extern struct uip_conn uip_conns[UIP_TCP_CONNS];
 #endif
 
 /**
@@ -1522,7 +1522,7 @@ struct uip_eth_hdr {
  * that are defined in this file. Please read below for more
  * information.
  */
-CCIF extern uint8_t uip_flags;
+extern uint8_t uip_flags;
 
 /* The following flags may be set in the global variable uip_flags
    before calling the application callback. The UIP_ACKDATA,
@@ -1934,17 +1934,17 @@ struct uip_udp_hdr {
 
 
 #if UIP_FIXEDADDR
-CCIF extern const uip_ipaddr_t uip_hostaddr, uip_netmask, uip_draddr;
+extern const uip_ipaddr_t uip_hostaddr, uip_netmask, uip_draddr;
 #else /* UIP_FIXEDADDR */
-CCIF extern uip_ipaddr_t uip_hostaddr, uip_netmask, uip_draddr;
+extern uip_ipaddr_t uip_hostaddr, uip_netmask, uip_draddr;
 #endif /* UIP_FIXEDADDR */
-CCIF extern const uip_ipaddr_t uip_broadcast_addr;
-CCIF extern const uip_ipaddr_t uip_all_zeroes_addr;
+extern const uip_ipaddr_t uip_broadcast_addr;
+extern const uip_ipaddr_t uip_all_zeroes_addr;
 
 #if UIP_FIXEDETHADDR
-CCIF extern const uip_lladdr_t uip_lladdr;
+extern const uip_lladdr_t uip_lladdr;
 #else
-CCIF extern uip_lladdr_t uip_lladdr;
+extern uip_lladdr_t uip_lladdr;
 #endif
 
 
diff --git a/os/net/ipv6/uiplib.h b/os/net/ipv6/uiplib.h
index 6b0d4ac84..6a122033e 100644
--- a/os/net/ipv6/uiplib.h
+++ b/os/net/ipv6/uiplib.h
@@ -73,8 +73,8 @@
 #define uiplib_ipaddrconv uiplib_ip4addrconv
 #endif /* NETSTACK_CONF_WITH_IPV6 */
 
-CCIF int uiplib_ip4addrconv(const char *addrstr, uip_ip4addr_t *addr);
-CCIF int uiplib_ip6addrconv(const char *addrstr, uip_ip6addr_t *addr);
+int uiplib_ip4addrconv(const char *addrstr, uip_ip4addr_t *addr);
+int uiplib_ip6addrconv(const char *addrstr, uip_ip6addr_t *addr);
 /** @} */
 
 /**
diff --git a/os/storage/cfs/cfs.h b/os/storage/cfs/cfs.h
index 3e2452c61..4851f562a 100644
--- a/os/storage/cfs/cfs.h
+++ b/os/storage/cfs/cfs.h
@@ -166,7 +166,7 @@ struct cfs_dirent {
  * \sa         cfs_close()
  */
 #ifndef cfs_open
-CCIF int cfs_open(const char *name, int flags);
+int cfs_open(const char *name, int flags);
 #endif
 
 /**
@@ -177,7 +177,7 @@ CCIF int cfs_open(const char *name, int flags);
  *             opened with cfs_open().
  */
 #ifndef cfs_close
-CCIF void cfs_close(int fd);
+void cfs_close(int fd);
 #endif
 
 /**
@@ -192,7 +192,7 @@ CCIF void cfs_close(int fd);
  *             cfs_open() and the CFS_READ flag.
  */
 #ifndef cfs_read
-CCIF int cfs_read(int fd, void *buf, unsigned int len);
+int cfs_read(int fd, void *buf, unsigned int len);
 #endif
 
 /**
@@ -207,7 +207,7 @@ CCIF int cfs_read(int fd, void *buf, unsigned int len);
  *             cfs_open() and the CFS_WRITE flag.
  */
 #ifndef cfs_write
-CCIF int cfs_write(int fd, const void *buf, unsigned int len);
+int cfs_write(int fd, const void *buf, unsigned int len);
 #endif
 
 /**
@@ -228,7 +228,7 @@ CCIF int cfs_write(int fd, const void *buf, unsigned int len);
  * \sa         CFS_SEEK_SET
  */
 #ifndef cfs_seek
-CCIF cfs_offset_t cfs_seek(int fd, cfs_offset_t offset, int whence);
+cfs_offset_t cfs_seek(int fd, cfs_offset_t offset, int whence);
 #endif
 
 /**
@@ -238,7 +238,7 @@ CCIF cfs_offset_t cfs_seek(int fd, cfs_offset_t offset, int whence);
  * \return -1  If the file could not be removed or if it doesn't exist.
  */
 #ifndef cfs_remove
-CCIF int cfs_remove(const char *name);
+int cfs_remove(const char *name);
 #endif
 
 /**
@@ -251,7 +251,7 @@ CCIF int cfs_remove(const char *name);
  * \sa         cfs_closedir()
  */
 #ifndef cfs_opendir
-CCIF int cfs_opendir(struct cfs_dir *dirp, const char *name);
+int cfs_opendir(struct cfs_dir *dirp, const char *name);
 #endif
 
 /**
@@ -265,7 +265,7 @@ CCIF int cfs_opendir(struct cfs_dir *dirp, const char *name);
  * \sa         cfs_closedir()
  */
 #ifndef cfs_readdir
-CCIF int cfs_readdir(struct cfs_dir *dirp, struct cfs_dirent *dirent);
+int cfs_readdir(struct cfs_dir *dirp, struct cfs_dirent *dirent);
 #endif
 
 /**
@@ -276,7 +276,7 @@ CCIF int cfs_readdir(struct cfs_dir *dirp, struct cfs_dirent *dirent);
  * \sa         cfs_readdir()
  */
 #ifndef cfs_closedir
-CCIF void cfs_closedir(struct cfs_dir *dirp);
+void cfs_closedir(struct cfs_dir *dirp);
 #endif
 
 #endif /* CFS_H_ */
diff --git a/os/sys/autostart.h b/os/sys/autostart.h
index 8a671b363..dcf91c4ef 100644
--- a/os/sys/autostart.h
+++ b/os/sys/autostart.h
@@ -50,7 +50,7 @@ struct process * const autostart_processes[] = {__VA_ARGS__, NULL}
 #error "C compiler must support __VA_ARGS__ macro"
 #endif
 
-CLIF extern struct process * const autostart_processes[];
+extern struct process * const autostart_processes[];
 
 void autostart_start(struct process * const processes[]);
 void autostart_exit(struct process * const processes[]);
diff --git a/os/sys/clock.h b/os/sys/clock.h
index 3aa25b22c..161527d47 100644
--- a/os/sys/clock.h
+++ b/os/sys/clock.h
@@ -98,7 +98,7 @@ void clock_init(void);
  *
  * \return The current clock time, measured in system ticks.
  */
-CCIF clock_time_t clock_time(void);
+clock_time_t clock_time(void);
 
 /**
  * Get the current value of the platform seconds.
@@ -108,7 +108,7 @@ CCIF clock_time_t clock_time(void);
  *
  * \return The value.
  */
-CCIF unsigned long clock_seconds(void);
+unsigned long clock_seconds(void);
 
 /**
  * Set the value of the platform seconds.
diff --git a/os/sys/etimer.h b/os/sys/etimer.h
index 59f665d10..02ad5df11 100644
--- a/os/sys/etimer.h
+++ b/os/sys/etimer.h
@@ -94,7 +94,7 @@ struct etimer {
  *             process that called the etimer_set() function.
  *
  */
-CCIF void etimer_set(struct etimer *et, clock_time_t interval);
+void etimer_set(struct etimer *et, clock_time_t interval);
 
 /**
  * \brief      Reset an event timer with the same interval as was
@@ -111,7 +111,7 @@ CCIF void etimer_set(struct etimer *et, clock_time_t interval);
  *
  * \sa etimer_restart()
  */
-CCIF void etimer_reset(struct etimer *et);
+void etimer_reset(struct etimer *et);
 
 /**
  * \brief      Reset an event timer with a new interval.
@@ -192,7 +192,7 @@ clock_time_t etimer_start_time(struct etimer *et);
  *             This function tests if an event timer has expired and
  *             returns true or false depending on its status.
  */
-CCIF int etimer_expired(struct etimer *et);
+int etimer_expired(struct etimer *et);
 
 /**
  * \brief      Stop a pending event timer.
diff --git a/os/sys/process.h b/os/sys/process.h
index bd206b6e7..5cffdb526 100644
--- a/os/sys/process.h
+++ b/os/sys/process.h
@@ -339,7 +339,7 @@ struct process {
  * process
  *
  */
-CCIF void process_start(struct process *p, process_data_t data);
+void process_start(struct process *p, process_data_t data);
 
 /**
  * Post an asynchronous event.
@@ -362,7 +362,7 @@ CCIF void process_start(struct process *p, process_data_t data);
  * \retval PROCESS_ERR_FULL The event queue was full and the event could
  * not be posted.
  */
-CCIF int process_post(struct process *p, process_event_t ev, process_data_t data);
+int process_post(struct process *p, process_event_t ev, process_data_t data);
 
 /**
  * Post a synchronous event to a process.
@@ -374,8 +374,8 @@ CCIF int process_post(struct process *p, process_event_t ev, process_data_t data
  * \param data A pointer to additional data that is posted together
  * with the event.
  */
-CCIF void process_post_synch(struct process *p,
-			     process_event_t ev, process_data_t data);
+void process_post_synch(struct process *p,
+                        process_event_t ev, process_data_t data);
 
 /**
  * \brief      Cause a process to exit
@@ -387,7 +387,7 @@ CCIF void process_post_synch(struct process *p,
  *
  * \sa PROCESS_CURRENT()
  */
-CCIF void process_exit(struct process *p);
+void process_exit(struct process *p);
 
 
 /**
@@ -400,7 +400,7 @@ CCIF void process_exit(struct process *p);
  * \hideinitializer
  */
 #define PROCESS_CURRENT() process_current
-CCIF extern struct process *process_current;
+extern struct process *process_current;
 
 /**
  * Switch context to another process
@@ -450,7 +450,7 @@ process_current = p
  * \note       There currently is no way to deallocate an allocated event
  *             number.
  */
-CCIF process_event_t process_alloc_event(void);
+process_event_t process_alloc_event(void);
 
 /** @} */
 
@@ -467,7 +467,7 @@ CCIF process_event_t process_alloc_event(void);
  *
  * \param p A pointer to the process' process structure.
  */
-CCIF void process_poll(struct process *p);
+void process_poll(struct process *p);
 
 /** @} */
 
@@ -509,7 +509,7 @@ int process_run(void);
  * \retval Non-zero if the process is running.
  * \retval Zero if the process is not running.
  */
-CCIF int process_is_running(struct process *p);
+int process_is_running(struct process *p);
 
 /**
  *  Number of events waiting to be processed.
@@ -521,7 +521,7 @@ int process_nevents(void);
 
 /** @} */
 
-CCIF extern struct process *process_list;
+extern struct process *process_list;
 
 #define PROCESS_LIST() process_list
 
diff --git a/os/sys/timer.h b/os/sys/timer.h
index b05963e47..54abcb3c2 100644
--- a/os/sys/timer.h
+++ b/os/sys/timer.h
@@ -84,10 +84,10 @@ struct timer {
   clock_time_t interval;
 };
 
-CCIF void timer_set(struct timer *t, clock_time_t interval);
+void timer_set(struct timer *t, clock_time_t interval);
 void timer_reset(struct timer *t);
 void timer_restart(struct timer *t);
-CCIF int timer_expired(struct timer *t);
+int timer_expired(struct timer *t);
 clock_time_t timer_remaining(struct timer *t);
 
 
diff --git a/tools/wpcapslip/contiki-conf.h b/tools/wpcapslip/contiki-conf.h
index 020cbdfec..7221f4033 100644
--- a/tools/wpcapslip/contiki-conf.h
+++ b/tools/wpcapslip/contiki-conf.h
@@ -1,8 +1,6 @@
 #ifndef CONTIKI_CONF_H_
 #define CONTIKI_CONF_H_
 #include <stdint.h>
-#define CCIF
-#define CLIF
 
 /* These names are deprecated, use C99 names. */
 typedef uint8_t   u8_t;