diff --git a/drivers/serial/serial.c b/drivers/serial/serial.c
index d9e71bbbe81..f02316ba602 100644
--- a/drivers/serial/serial.c
+++ b/drivers/serial/serial.c
@@ -1354,7 +1354,6 @@ static int uart_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
             }
             break;
 
-#ifdef CONFIG_SERIAL_TERMIOS
           case TCFLSH:
             {
               /* Empty the tx/rx buffers */
@@ -1391,7 +1390,6 @@ static int uart_ioctl(FAR struct file *filep, int cmd, unsigned long arg)
               ret = uart_tcdrain(dev, true, 10 * TICK_PER_SEC);
             }
             break;
-#endif
 
 #if defined(CONFIG_TTY_SIGINT) || defined(CONFIG_TTY_SIGTSTP)
           /* Make the controlling terminal of the calling process */
diff --git a/include/cxx/cunistd b/include/cxx/cunistd
index 42ae1254106..91fd6259289 100644
--- a/include/cxx/cunistd
+++ b/include/cxx/cunistd
@@ -56,9 +56,7 @@ namespace std
 
   // Terminal I/O
 
-#ifdef CONFIG_SERIAL_TERMIOS
   using ::isatty;
-#endif
 
   // Memory management
 
diff --git a/include/nuttx/serial/serial.h b/include/nuttx/serial/serial.h
index 6645da5183e..d5aa79313d8 100644
--- a/include/nuttx/serial/serial.h
+++ b/include/nuttx/serial/serial.h
@@ -31,9 +31,7 @@
 #include <stdint.h>
 #include <stdbool.h>
 #include <errno.h>
-#ifdef CONFIG_SERIAL_TERMIOS
-#  include <termios.h>
-#endif
+#include <termios.h>
 
 #include <nuttx/fs/fs.h>
 #include <nuttx/semaphore.h>
diff --git a/include/termios.h b/include/termios.h
index 924c88c2271..a96672446dd 100644
--- a/include/termios.h
+++ b/include/termios.h
@@ -29,8 +29,6 @@
 #include <sys/types.h>
 #include <stdint.h>
 
-#ifdef CONFIG_SERIAL_TERMIOS
-
 /****************************************************************************
  * Pre-processor Definitions
  ****************************************************************************/
@@ -319,5 +317,4 @@ int tcsetattr(int fd, int options, FAR const struct termios *termiosp);
 }
 #endif
 
-#endif /* CONFIG_SERIAL_TERMIOS */
 #endif /* __INCLUDE_TERMIOS_H */
diff --git a/include/unistd.h b/include/unistd.h
index 63e5cdd5065..d6092e1f221 100644
--- a/include/unistd.h
+++ b/include/unistd.h
@@ -327,14 +327,12 @@ ssize_t pwrite(int fd, FAR const void *buf, size_t nbytes, off_t offset);
 int     ftruncate(int fd, off_t length);
 int     fchown(int fd, uid_t owner, gid_t group);
 
-#ifdef CONFIG_SERIAL_TERMIOS
 /* Check if a file descriptor corresponds to a terminal I/O file */
 
 int     isatty(int fd);
 
 FAR char *ttyname(int fd);
 int       ttyname_r(int fd, FAR char *buf, size_t buflen);
-#endif
 
 /* Memory management */
 
diff --git a/libs/libc/termios/Make.defs b/libs/libc/termios/Make.defs
index 974bc063e0e..ec44a79391e 100644
--- a/libs/libc/termios/Make.defs
+++ b/libs/libc/termios/Make.defs
@@ -21,8 +21,6 @@
 # termios.h support requires file descriptors and that CONFIG_SERIAL_TERMIOS
 # is defined
 
-ifeq ($(CONFIG_SERIAL_TERMIOS),y)
-
 # Add the termios C files to the build
 
 CSRCS += lib_cfspeed.c lib_cfmakeraw.c lib_isatty.c lib_tcflush.c
@@ -33,5 +31,3 @@ CSRCS += lib_ttyname.c lib_ttynamer.c
 
 DEPPATH += --dep-path termios
 VPATH += termios
-
-endif
diff --git a/libs/libc/termios/lib_tcgetattr.c b/libs/libc/termios/lib_tcgetattr.c
index 61dae53a0ba..a1bbcdc3bdd 100644
--- a/libs/libc/termios/lib_tcgetattr.c
+++ b/libs/libc/termios/lib_tcgetattr.c
@@ -60,5 +60,5 @@
 
 int tcgetattr(int fd, FAR struct termios *termiosp)
 {
-  return ioctl(fd, TCGETS, (unsigned long)termiosp);
+  return ioctl(fd, TCGETS, (unsigned long)(uintptr_t)termiosp);
 }
diff --git a/libs/libc/termios/lib_tcsetattr.c b/libs/libc/termios/lib_tcsetattr.c
index cde1c0663c6..8142087f585 100644
--- a/libs/libc/termios/lib_tcsetattr.c
+++ b/libs/libc/termios/lib_tcsetattr.c
@@ -93,5 +93,5 @@ int tcsetattr(int fd, int options, FAR const struct termios *termiosp)
       tcflush(fd, TCIFLUSH);
     }
 
-  return ioctl(fd, TCSETS, (unsigned long)termiosp);
+  return ioctl(fd, TCSETS, (unsigned long)(uintptr_t)termiosp);
 }