diff --git a/arch/sim/src/up_wpcap.c b/arch/sim/src/up_wpcap.c
index 6225751db6a..69c808c5327 100644
--- a/arch/sim/src/up_wpcap.c
+++ b/arch/sim/src/up_wpcap.c
@@ -50,6 +50,7 @@
 #include <winsock2.h>
 #include <iphlpapi.h>
 
+#include <sys/time.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <malloc.h>
diff --git a/drivers/wireless/cc3000/cc3000.c b/drivers/wireless/cc3000/cc3000.c
index f264136adc1..c9cea31e177 100644
--- a/drivers/wireless/cc3000/cc3000.c
+++ b/drivers/wireless/cc3000/cc3000.c
@@ -48,6 +48,7 @@
 #include <nuttx/config.h>
 
 #include <sys/types.h>
+#include <sys/time.h>
 
 #include <stdint.h>
 #include <stdbool.h>
diff --git a/drivers/wireless/cc3000/cc3000_socket.h b/drivers/wireless/cc3000/cc3000_socket.h
index 02144fe90de..4287e9cf5d0 100644
--- a/drivers/wireless/cc3000/cc3000_socket.h
+++ b/drivers/wireless/cc3000/cc3000_socket.h
@@ -387,6 +387,8 @@ long cc3000_connect_impl(long sd, FAR const struct sockaddr *addr, socklen_t add
  *
  *****************************************************************************/
 
+struct timeval;
+
 int cc3000_select_impl(long nfds, TICC3000fd_set *readfds, TICC3000fd_set *writefds,TICC3000fd_set *exceptfds,
            struct timeval *timeout);
 
diff --git a/drivers/wireless/cc3000/socket.c b/drivers/wireless/cc3000/socket.c
index e15cf500ded..87d7f4dacb5 100644
--- a/drivers/wireless/cc3000/socket.c
+++ b/drivers/wireless/cc3000/socket.c
@@ -38,6 +38,7 @@
 
 #include <sys/types.h>
 #include <sys/select.h>
+#include <sys/time.h>
 
 #include <stdio.h>
 #include <string.h>
diff --git a/drivers/wireless/cc3000/socket_imp.c b/drivers/wireless/cc3000/socket_imp.c
index 7354f04fe40..d52fe270d37 100644
--- a/drivers/wireless/cc3000/socket_imp.c
+++ b/drivers/wireless/cc3000/socket_imp.c
@@ -39,11 +39,13 @@
  * Included Files
  *****************************************************************************/
 
+#include <sys/time.h>
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
 #include <debug.h>
 #include <stdlib.h>
+
 #include <nuttx/wireless/cc3000/hci.h>
 #include "cc3000_socket.h"
 #include <nuttx/wireless/cc3000/evnt_handler.h>
diff --git a/fs/nfs/rpc_clnt.c b/fs/nfs/rpc_clnt.c
index e1958840459..ea62e105324 100644
--- a/fs/nfs/rpc_clnt.c
+++ b/fs/nfs/rpc_clnt.c
@@ -79,6 +79,7 @@
  ****************************************************************************/
 
 #include <sys/socket.h>
+#include <sys/time.h>
 #include <queue.h>
 #include <time.h>
 #include <netinet/in.h>
diff --git a/fs/vfs/fs_select.c b/fs/vfs/fs_select.c
index 33a7a11bcf2..0edb8efbd58 100644
--- a/fs/vfs/fs_select.c
+++ b/fs/vfs/fs_select.c
@@ -40,6 +40,7 @@
 #include <nuttx/config.h>
 
 #include <sys/select.h>
+#include <sys/time.h>
 
 #include <string.h>
 #include <poll.h>
diff --git a/include/nuttx/wireless/cc3000/include/sys/socket.h b/include/nuttx/wireless/cc3000/include/sys/socket.h
index 77a0f1b2e4b..6eb1df2ef30 100644
--- a/include/nuttx/wireless/cc3000/include/sys/socket.h
+++ b/include/nuttx/wireless/cc3000/include/sys/socket.h
@@ -288,6 +288,7 @@ int connect(int sockfd, FAR const struct sockaddr *addr, socklen_t addrlen);
  *
  *****************************************************************************/
 
+struct timeval;
 int cc3000_select(int nfds, fd_set *readfds, fd_set *writefds,fd_set *exceptfds,
                   struct timeval *timeout);
 
diff --git a/include/sys/select.h b/include/sys/select.h
index 1ff074b6c42..6ce8ff86152 100644
--- a/include/sys/select.h
+++ b/include/sys/select.h
@@ -104,13 +104,15 @@ typedef uint32_t fd_set[__SELECT_NUINT32];
 #undef EXTERN
 #if defined(__cplusplus)
 #define EXTERN extern "C"
-extern "C" {
+extern "C"
+{
 #else
 #define EXTERN extern
 #endif
 
-EXTERN int select(int nfds, FAR fd_set *readfds, FAR fd_set *writefds,
-                  FAR fd_set *exceptfds, FAR struct timeval *timeout);
+struct timeval;
+int select(int nfds, FAR fd_set *readfds, FAR fd_set *writefds,
+           FAR fd_set *exceptfds, FAR struct timeval *timeout);
 
 #undef EXTERN
 #if defined(__cplusplus)
diff --git a/include/sys/types.h b/include/sys/types.h
index 530434b2296..102bde62241 100644
--- a/include/sys/types.h
+++ b/include/sys/types.h
@@ -94,8 +94,9 @@
 #define PRIOR_OTHER_MIN   0
 #define PRIOR_OTHER_MAX 255
 
-/* Scheduling Priorities.  NOTE:  Only the idle task can take
- * the true minimum priority. */
+/* Scheduling Priorities.  NOTE:  Only the idle task can take the true
+ * minimum priority.
+ */
 
 #define SCHED_PRIORITY_MAX     255
 #define SCHED_PRIORITY_DEFAULT 100
diff --git a/include/time.h b/include/time.h
index 832927ea824..c43385acea6 100644
--- a/include/time.h
+++ b/include/time.h
@@ -159,12 +159,6 @@ struct sigevent;
  * Public Data
  ********************************************************************************/
 
-/* extern char *tznames[]; not supported */
-
-/********************************************************************************
- * Public Function Prototypes
- ********************************************************************************/
-
 #undef EXTERN
 #if defined(__cplusplus)
 #define EXTERN extern "C"
@@ -174,6 +168,19 @@ extern "C"
 #define EXTERN extern
 #endif
 
+/* daylight - Daylight savings time flag */
+/* EXTERN int daylight; not supported */
+
+/* timezone - Difference from UTC and local standard time
+/* EXTERN long int timezone; not supported */
+
+/* tzname[] - Timezone strings */
+/* EXTERN FAR char *tzname[]; not supported */
+
+/********************************************************************************
+ * Public Function Prototypes
+ ********************************************************************************/
+
 clock_t clock(void);
 
 int clock_settime(clockid_t clockid, FAR const struct timespec *tp);
diff --git a/net/socket/getsockopt.c b/net/socket/getsockopt.c
index 60c316471d3..2af5dce60c2 100644
--- a/net/socket/getsockopt.c
+++ b/net/socket/getsockopt.c
@@ -42,6 +42,7 @@
 
 #include <sys/types.h>
 #include <sys/socket.h>
+#include <sys/time.h>
 #include <errno.h>
 
 #include "socket/socket.h"
diff --git a/net/socket/setsockopt.c b/net/socket/setsockopt.c
index 7784b652061..61e502ddfd8 100644
--- a/net/socket/setsockopt.c
+++ b/net/socket/setsockopt.c
@@ -43,6 +43,7 @@
 
 #include <sys/types.h>
 #include <sys/socket.h>
+#include <sys/time.h>
 #include <errno.h>
 #include <arch/irq.h>
 
diff --git a/net/utils/net_dsec2timeval.c b/net/utils/net_dsec2timeval.c
index df6db20dbab..b454844fa66 100644
--- a/net/utils/net_dsec2timeval.c
+++ b/net/utils/net_dsec2timeval.c
@@ -40,8 +40,10 @@
 #include <nuttx/config.h>
 
 #include <sys/socket.h>
+#include <sys/time.h>
 #include <stdint.h>
 #include <errno.h>
+
 #include <nuttx/clock.h>
 
 #include "utils/utils.h"
diff --git a/net/utils/net_timeval2dsec.c b/net/utils/net_timeval2dsec.c
index af67cdc4eb6..b4beaf4eff2 100644
--- a/net/utils/net_timeval2dsec.c
+++ b/net/utils/net_timeval2dsec.c
@@ -39,6 +39,8 @@
 
 #include <nuttx/config.h>
 
+#include <sys/time.h>
+
 #include <nuttx/clock.h>
 
 #include "utils/utils.h"