diff --git a/libc/include/sys/capability.h b/libc/include/sys/capability.h
index 7718a6c..b9a40b3 100644
--- a/libc/include/sys/capability.h
+++ b/libc/include/sys/capability.h
@@ -34,8 +34,8 @@
 
 __BEGIN_DECLS
 
-extern int capget(cap_user_header_t hdrp, cap_user_data_t datap);
-extern int capset(cap_user_header_t hdrp, const cap_user_data_t datap);
+int capget(cap_user_header_t hdrp, cap_user_data_t datap);
+int capset(cap_user_header_t hdrp, const cap_user_data_t datap);
 
 __END_DECLS
 
diff --git a/libc/include/sys/eventfd.h b/libc/include/sys/eventfd.h
index 4c8da0c..6b9749a 100644
--- a/libc/include/sys/eventfd.h
+++ b/libc/include/sys/eventfd.h
@@ -40,10 +40,10 @@
 /* type of event counter */
 typedef uint64_t eventfd_t;
 
-extern int eventfd(unsigned int initial_value, int flags);
+int eventfd(unsigned int initial_value, int flags);
 
-extern int eventfd_read(int fd, eventfd_t* value);
-extern int eventfd_write(int fd, eventfd_t value);
+int eventfd_read(int fd, eventfd_t* value);
+int eventfd_write(int fd, eventfd_t value);
 
 __END_DECLS
 
diff --git a/libc/include/sys/fsuid.h b/libc/include/sys/fsuid.h
index 223db90..e4d9ebc 100644
--- a/libc/include/sys/fsuid.h
+++ b/libc/include/sys/fsuid.h
@@ -34,8 +34,8 @@
 
 __BEGIN_DECLS
 
-extern int setfsuid(uid_t) __INTRODUCED_IN(21);
-extern int setfsgid(gid_t) __INTRODUCED_IN(21);
+int setfsuid(uid_t) __INTRODUCED_IN(21);
+int setfsgid(gid_t) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/inotify.h b/libc/include/sys/inotify.h
index dcf0e1d..2e99144 100644
--- a/libc/include/sys/inotify.h
+++ b/libc/include/sys/inotify.h
@@ -40,10 +40,10 @@
 #define IN_CLOEXEC O_CLOEXEC
 #define IN_NONBLOCK O_NONBLOCK
 
-extern int inotify_init(void);
-extern int inotify_init1(int) __INTRODUCED_IN(21);
-extern int inotify_add_watch(int, const char*, uint32_t);
-extern int inotify_rm_watch(int, uint32_t);
+int inotify_init(void);
+int inotify_init1(int) __INTRODUCED_IN(21);
+int inotify_add_watch(int, const char*, uint32_t);
+int inotify_rm_watch(int, uint32_t);
 
 __END_DECLS
 
diff --git a/libc/include/sys/ipc.h b/libc/include/sys/ipc.h
index c0ae0ba..99bc5db 100644
--- a/libc/include/sys/ipc.h
+++ b/libc/include/sys/ipc.h
@@ -25,6 +25,7 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
 #ifndef _SYS_IPC_H
 #define _SYS_IPC_H
 
@@ -34,7 +35,7 @@
 
 __BEGIN_DECLS
 
-extern key_t  ftok(const char*  path, int  id);
+key_t ftok(const char* path, int id);
 
 __END_DECLS
 
diff --git a/libc/include/sys/klog.h b/libc/include/sys/klog.h
index acfaa20..47eb3a4 100644
--- a/libc/include/sys/klog.h
+++ b/libc/include/sys/klog.h
@@ -46,7 +46,7 @@
 #define KLOG_SIZE_UNREAD   9
 #define KLOG_SIZE_BUFFER   10
 
-extern int klogctl(int, char *, int);
+int klogctl(int, char *, int);
 
 __END_DECLS
 
diff --git a/libc/include/sys/mount.h b/libc/include/sys/mount.h
index fd7cf17..26c0e0f 100644
--- a/libc/include/sys/mount.h
+++ b/libc/include/sys/mount.h
@@ -41,9 +41,9 @@
 #define MNT_EXPIRE 4
 #define UMOUNT_NOFOLLOW 8
 
-extern int mount(const char*, const char*, const char*, unsigned long, const void*);
-extern int umount(const char*);
-extern int umount2(const char*, int);
+int mount(const char*, const char*, const char*, unsigned long, const void*);
+int umount(const char*);
+int umount2(const char*, int);
 
 __END_DECLS
 
diff --git a/libc/include/sys/personality.h b/libc/include/sys/personality.h
index 15a5e68..6f3a3c9 100644
--- a/libc/include/sys/personality.h
+++ b/libc/include/sys/personality.h
@@ -34,7 +34,7 @@
 
 __BEGIN_DECLS
 
-extern int personality(unsigned int persona) __INTRODUCED_IN(15);
+int personality(unsigned int persona) __INTRODUCED_IN(15);
 
 __END_DECLS
 
diff --git a/libc/include/sys/prctl.h b/libc/include/sys/prctl.h
index d96b8b6..742ed57 100644
--- a/libc/include/sys/prctl.h
+++ b/libc/include/sys/prctl.h
@@ -35,7 +35,7 @@
 
 __BEGIN_DECLS
 
-extern int prctl(int option, ...);
+int prctl(int option, ...);
 
 __END_DECLS
 
diff --git a/libc/include/sys/reboot.h b/libc/include/sys/reboot.h
index 7d202f7..df4739e 100644
--- a/libc/include/sys/reboot.h
+++ b/libc/include/sys/reboot.h
@@ -25,6 +25,7 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
 #ifndef _SYS_REBOOT_H_
 #define _SYS_REBOOT_H_
 
@@ -41,7 +42,7 @@
 #define RB_DISABLE_CAD  LINUX_REBOOT_CMD_CAD_OFF
 #define RB_POWER_OFF    LINUX_REBOOT_CMD_POWER_OFF
 
-extern int reboot(int  reboot_type);
+int reboot(int reboot_type);
 
 __END_DECLS
 
diff --git a/libc/include/sys/resource.h b/libc/include/sys/resource.h
index 3187420..248310e 100644
--- a/libc/include/sys/resource.h
+++ b/libc/include/sys/resource.h
@@ -42,20 +42,20 @@
 
 typedef unsigned long rlim_t;
 
-extern int getrlimit(int, struct rlimit*);
-extern int setrlimit(int, const struct rlimit*);
+int getrlimit(int, struct rlimit*);
+int setrlimit(int, const struct rlimit*);
 
-extern int getrlimit64(int, struct rlimit64*) __INTRODUCED_IN(21);
-extern int setrlimit64(int, const struct rlimit64*) __INTRODUCED_IN(21);
+int getrlimit64(int, struct rlimit64*) __INTRODUCED_IN(21);
+int setrlimit64(int, const struct rlimit64*) __INTRODUCED_IN(21);
 
-extern int getpriority(int, int);
-extern int setpriority(int, int, int);
+int getpriority(int, int);
+int setpriority(int, int, int);
 
-extern int getrusage(int, struct rusage*);
+int getrusage(int, struct rusage*);
 
-extern int prlimit(pid_t, int, const struct rlimit*, struct rlimit*) __INTRODUCED_IN_32(24)
+int prlimit(pid_t, int, const struct rlimit*, struct rlimit*) __INTRODUCED_IN_32(24)
   __INTRODUCED_IN_64(21);
-extern int prlimit64(pid_t, int, const struct rlimit64*, struct rlimit64*) __INTRODUCED_IN(21);
+int prlimit64(pid_t, int, const struct rlimit64*, struct rlimit64*) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/select.h b/libc/include/sys/select.h
index 96d735e..0f454b0 100644
--- a/libc/include/sys/select.h
+++ b/libc/include/sys/select.h
@@ -57,9 +57,9 @@
     } \
   } while (0)
 
-extern void __FD_CLR_chk(int, fd_set*, size_t) __INTRODUCED_IN(21);
-extern void __FD_SET_chk(int, fd_set*, size_t) __INTRODUCED_IN(21);
-extern int __FD_ISSET_chk(int, fd_set*, size_t) __INTRODUCED_IN(21);
+void __FD_CLR_chk(int, fd_set*, size_t) __INTRODUCED_IN(21);
+void __FD_SET_chk(int, fd_set*, size_t) __INTRODUCED_IN(21);
+int __FD_ISSET_chk(int, fd_set*, size_t) __INTRODUCED_IN(21);
 
 #if defined(__BIONIC_FORTIFY)
 #define FD_CLR(fd, set) __FD_CLR_chk(fd, set, __bos(set))
@@ -71,8 +71,8 @@
 #define FD_ISSET(fd, set) ((__FDS_BITS(set)[__FDELT(fd)] & __FDMASK(fd)) != 0)
 #endif /* defined(__BIONIC_FORTIFY) */
 
-extern int select(int, fd_set*, fd_set*, fd_set*, struct timeval*);
-extern int pselect(int, fd_set*, fd_set*, fd_set*, const struct timespec*, const sigset_t*);
+int select(int, fd_set*, fd_set*, fd_set*, struct timeval*);
+int pselect(int, fd_set*, fd_set*, fd_set*, const struct timespec*, const sigset_t*);
 
 __END_DECLS
 
diff --git a/libc/include/sys/sendfile.h b/libc/include/sys/sendfile.h
index f90498a..3ac8fdf 100644
--- a/libc/include/sys/sendfile.h
+++ b/libc/include/sys/sendfile.h
@@ -35,12 +35,12 @@
 __BEGIN_DECLS
 
 #if defined(__USE_FILE_OFFSET64)
-extern ssize_t sendfile(int out_fd, int in_fd, off_t* offset, size_t count) __RENAME(sendfile64)
+ssize_t sendfile(int out_fd, int in_fd, off_t* offset, size_t count) __RENAME(sendfile64)
   __INTRODUCED_IN(21);
 #else
-extern ssize_t sendfile(int out_fd, int in_fd, off_t* offset, size_t count);
+ssize_t sendfile(int out_fd, int in_fd, off_t* offset, size_t count);
 #endif
-extern ssize_t sendfile64(int out_fd, int in_fd, off64_t* offset, size_t count) __INTRODUCED_IN(21);
+ssize_t sendfile64(int out_fd, int in_fd, off64_t* offset, size_t count) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/signalfd.h b/libc/include/sys/signalfd.h
index 41036b0..a21c57b 100644
--- a/libc/include/sys/signalfd.h
+++ b/libc/include/sys/signalfd.h
@@ -35,7 +35,7 @@
 
 __BEGIN_DECLS
 
-extern int signalfd(int fd, const sigset_t* _Nonnull mask, int flags) __INTRODUCED_IN(18);
+int signalfd(int fd, const sigset_t* _Nonnull mask, int flags) __INTRODUCED_IN(18);
 
 __END_DECLS
 
diff --git a/libc/include/sys/socket.h b/libc/include/sys/socket.h
index 9736ba8..40b9d37 100644
--- a/libc/include/sys/socket.h
+++ b/libc/include/sys/socket.h
@@ -287,16 +287,16 @@
 __socketcall int socket(int, int, int);
 __socketcall int socketpair(int, int, int, int*);
 
-extern ssize_t send(int, const void*, size_t, int);
-extern ssize_t recv(int, void*, size_t, int);
+ssize_t send(int, const void*, size_t, int);
+ssize_t recv(int, void*, size_t, int);
 
 __socketcall ssize_t sendto(int, const void*, size_t, int, const struct sockaddr*, socklen_t);
 __socketcall ssize_t recvfrom(int, void*, size_t, int, const struct sockaddr*, socklen_t*);
 
 __errordecl(__recvfrom_error, "recvfrom called with size bigger than buffer");
-extern ssize_t __recvfrom_chk(int, void*, size_t, size_t, int, const struct sockaddr*, socklen_t*)
+ssize_t __recvfrom_chk(int, void*, size_t, size_t, int, const struct sockaddr*, socklen_t*)
   __INTRODUCED_IN(21);
-extern ssize_t __recvfrom_real(int, void*, size_t, int, const struct sockaddr*, socklen_t*) __RENAME(recvfrom);
+ssize_t __recvfrom_real(int, void*, size_t, int, const struct sockaddr*, socklen_t*) __RENAME(recvfrom);
 
 #if defined(__BIONIC_FORTIFY)
 
diff --git a/libc/include/sys/stat.h b/libc/include/sys/stat.h
index a65f27a..4397a0d 100644
--- a/libc/include/sys/stat.h
+++ b/libc/include/sys/stat.h
@@ -141,24 +141,24 @@
 #define S_IEXEC S_IXUSR
 #endif
 
-extern int chmod(const char*, mode_t);
-extern int fchmod(int, mode_t);
-extern int mkdir(const char*, mode_t);
+int chmod(const char*, mode_t);
+int fchmod(int, mode_t);
+int mkdir(const char*, mode_t);
 
-extern int fstat(int, struct stat*);
-extern int fstat64(int, struct stat64*) __INTRODUCED_IN(21);
-extern int fstatat(int, const char*, struct stat*, int);
-extern int fstatat64(int, const char*, struct stat64*, int) __INTRODUCED_IN(21);
-extern int lstat(const char*, struct stat*);
-extern int lstat64(const char*, struct stat64*) __INTRODUCED_IN(21);
-extern int stat(const char*, struct stat*);
-extern int stat64(const char*, struct stat64*) __INTRODUCED_IN(21);
+int fstat(int, struct stat*);
+int fstat64(int, struct stat64*) __INTRODUCED_IN(21);
+int fstatat(int, const char*, struct stat*, int);
+int fstatat64(int, const char*, struct stat64*, int) __INTRODUCED_IN(21);
+int lstat(const char*, struct stat*);
+int lstat64(const char*, struct stat64*) __INTRODUCED_IN(21);
+int stat(const char*, struct stat*);
+int stat64(const char*, struct stat64*) __INTRODUCED_IN(21);
 
-extern int mknod(const char*, mode_t, dev_t);
-extern mode_t umask(mode_t);
+int mknod(const char*, mode_t, dev_t);
+mode_t umask(mode_t);
 
-extern mode_t __umask_chk(mode_t) __INTRODUCED_IN(18);
-extern mode_t __umask_real(mode_t) __RENAME(umask);
+mode_t __umask_chk(mode_t) __INTRODUCED_IN(18);
+mode_t __umask_real(mode_t) __RENAME(umask);
 __errordecl(__umask_invalid_mode, "umask called with invalid mode");
 
 #if defined(__BIONIC_FORTIFY)
@@ -183,17 +183,17 @@
 // Implemented as a static inline before 21.
 #endif
 
-extern int mkfifoat(int, const char*, mode_t) __INTRODUCED_IN(23);
+int mkfifoat(int, const char*, mode_t) __INTRODUCED_IN(23);
 
-extern int fchmodat(int, const char*, mode_t, int);
-extern int mkdirat(int, const char*, mode_t);
-extern int mknodat(int, const char*, mode_t, dev_t) __INTRODUCED_IN(21);
+int fchmodat(int, const char*, mode_t, int);
+int mkdirat(int, const char*, mode_t);
+int mknodat(int, const char*, mode_t, dev_t) __INTRODUCED_IN(21);
 
 #define UTIME_NOW  ((1L << 30) - 1L)
 #define UTIME_OMIT ((1L << 30) - 2L)
-extern int utimensat(int fd, const char* path, const struct timespec times[2], int flags)
+int utimensat(int fd, const char* path, const struct timespec times[2], int flags)
   __INTRODUCED_IN(12);
-extern int futimens(int fd, const struct timespec times[2]) __INTRODUCED_IN(19);
+int futimens(int fd, const struct timespec times[2]) __INTRODUCED_IN(19);
 
 __END_DECLS
 
diff --git a/libc/include/sys/statvfs.h b/libc/include/sys/statvfs.h
index f6b9803..af1b9c0 100644
--- a/libc/include/sys/statvfs.h
+++ b/libc/include/sys/statvfs.h
@@ -59,12 +59,12 @@
 #define ST_NODIRATIME  0x0800
 #define ST_RELATIME    0x1000
 
-extern int statvfs(const char* __restrict _Nonnull, struct statvfs* __restrict _Nonnull)
+int statvfs(const char* __restrict _Nonnull, struct statvfs* __restrict _Nonnull)
   __INTRODUCED_IN(19);
-extern int statvfs64(const char* __restrict _Nonnull, struct statvfs64* __restrict _Nonnull)
+int statvfs64(const char* __restrict _Nonnull, struct statvfs64* __restrict _Nonnull)
   __INTRODUCED_IN(21);
-extern int fstatvfs(int, struct statvfs* _Nonnull) __INTRODUCED_IN(19);
-extern int fstatvfs64(int, struct statvfs64* _Nonnull) __INTRODUCED_IN(21);
+int fstatvfs(int, struct statvfs* _Nonnull) __INTRODUCED_IN(19);
+int fstatvfs64(int, struct statvfs64* _Nonnull) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/swap.h b/libc/include/sys/swap.h
index 2d99df8..3444736 100644
--- a/libc/include/sys/swap.h
+++ b/libc/include/sys/swap.h
@@ -38,8 +38,8 @@
 #define SWAP_FLAG_PRIO_MASK 0x7fff
 #define SWAP_FLAG_PRIO_SHIFT 0
 
-extern int swapon(const char* _Nonnull, int) __INTRODUCED_IN(19);
-extern int swapoff(const char* _Nonnull) __INTRODUCED_IN(19);
+int swapon(const char* _Nonnull, int) __INTRODUCED_IN(19);
+int swapoff(const char* _Nonnull) __INTRODUCED_IN(19);
 
 __END_DECLS
 
diff --git a/libc/include/sys/timerfd.h b/libc/include/sys/timerfd.h
index 0090233..a500060 100644
--- a/libc/include/sys/timerfd.h
+++ b/libc/include/sys/timerfd.h
@@ -42,10 +42,9 @@
 #define TFD_CLOEXEC O_CLOEXEC
 #define TFD_NONBLOCK O_NONBLOCK
 
-extern int timerfd_create(clockid_t, int) __INTRODUCED_IN(19);
-extern int timerfd_settime(int, int, const struct itimerspec*, struct itimerspec*)
-  __INTRODUCED_IN(19);
-extern int timerfd_gettime(int, struct itimerspec*) __INTRODUCED_IN(19);
+int timerfd_create(clockid_t, int) __INTRODUCED_IN(19);
+int timerfd_settime(int, int, const struct itimerspec*, struct itimerspec*) __INTRODUCED_IN(19);
+int timerfd_gettime(int, struct itimerspec*) __INTRODUCED_IN(19);
 
 __END_DECLS
 
diff --git a/libc/include/sys/times.h b/libc/include/sys/times.h
index 6ce5b55..f52db1f 100644
--- a/libc/include/sys/times.h
+++ b/libc/include/sys/times.h
@@ -35,7 +35,7 @@
 
 __BEGIN_DECLS
 
-extern clock_t times(struct tms*);
+clock_t times(struct tms*);
 
 __END_DECLS
 
diff --git a/libc/include/sys/utsname.h b/libc/include/sys/utsname.h
index d54a994..b3856a7 100644
--- a/libc/include/sys/utsname.h
+++ b/libc/include/sys/utsname.h
@@ -25,6 +25,7 @@
  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
 #ifndef _SYS_UTSNAME_H_
 #define _SYS_UTSNAME_H_
 
@@ -43,7 +44,7 @@
     char  domainname[SYS_NMLN];
 };
 
-extern int uname(struct utsname *);
+int uname(struct utsname*);
 
 __END_DECLS
 
diff --git a/libc/include/sys/vfs.h b/libc/include/sys/vfs.h
index bf094dc..1231eb1 100644
--- a/libc/include/sys/vfs.h
+++ b/libc/include/sys/vfs.h
@@ -137,10 +137,10 @@
 #define XENIX_SUPER_MAGIC     0x012FF7B4
 #define XFS_SUPER_MAGIC       0x58465342
 
-extern int statfs(const char* _Nonnull, struct statfs* _Nonnull);
-extern int statfs64(const char* _Nonnull, struct statfs64* _Nonnull) __INTRODUCED_IN(21);
-extern int fstatfs(int, struct statfs* _Nonnull);
-extern int fstatfs64(int, struct statfs64* _Nonnull) __INTRODUCED_IN(21);
+int statfs(const char* _Nonnull, struct statfs* _Nonnull);
+int statfs64(const char* _Nonnull, struct statfs64* _Nonnull) __INTRODUCED_IN(21);
+int fstatfs(int, struct statfs* _Nonnull);
+int fstatfs64(int, struct statfs64* _Nonnull) __INTRODUCED_IN(21);
 
 __END_DECLS
 
diff --git a/libc/include/sys/wait.h b/libc/include/sys/wait.h
index e0afabc..90eb35b 100644
--- a/libc/include/sys/wait.h
+++ b/libc/include/sys/wait.h
@@ -49,9 +49,9 @@
 #define W_EXITCODE(ret, sig)    ((ret) << 8 | (sig))
 #define W_STOPCODE(sig)         ((sig) << 8 | 0x7f)
 
-extern pid_t  wait(int *);
-extern pid_t  waitpid(pid_t, int *, int);
-extern pid_t wait4(pid_t, int*, int, struct rusage*) __INTRODUCED_IN(18);
+pid_t wait(int*);
+pid_t waitpid(pid_t, int*, int);
+pid_t wait4(pid_t, int*, int, struct rusage*) __INTRODUCED_IN(18);
 
 /* Posix states that idtype_t should be an enumeration type, but
  * the kernel headers define P_ALL, P_PID and P_PGID as constant macros
@@ -59,7 +59,7 @@
  */
 typedef int idtype_t;
 
-extern int  waitid(idtype_t which, id_t id, siginfo_t *info, int options);
+int waitid(idtype_t which, id_t id, siginfo_t* info, int options);
 
 __END_DECLS