use restrict everywhere it's required by c99 and/or posix 2008

to deal with the fact that the public headers may be used with pre-c99
compilers, __restrict is used in place of restrict, and defined
appropriately for any supported compiler. we also avoid the form
[restrict] since older versions of gcc rejected it due to a bug in the
original c99 standard, and instead use the form *restrict.

28 files changed, 353 insertions, 184 deletions

diff --git a/include/aio.h b/include/aio.h
index 2edd5a2e..3e351348 100644
--- a/include/aio.h
+++ b/include/aio.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #include <signal.h>
 #include <time.h>
 
@@ -46,7 +52,7 @@ int aio_cancel(int, struct aiocb *);
 int aio_suspend(const struct aiocb *const [], int, const struct timespec *);
 int aio_fsync(int, struct aiocb *);
 
-int lio_listio(int, struct aiocb *const [], int, struct sigevent *);
+int lio_listio(int, struct aiocb *__restrict const *__restrict, int, struct sigevent *__restrict);
 
 #if defined(_LARGEFILE64_SOURCE) || defined(_GNU_SOURCE)
 #define aiocb64 aiocb
diff --git a/include/arpa/inet.h b/include/arpa/inet.h
index b604f60b..82e2ac1b 100644
--- a/include/arpa/inet.h
+++ b/include/arpa/inet.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #include <netinet/in.h>
 #include <inttypes.h>
 
@@ -24,8 +30,8 @@ uint16_t ntohs(uint16_t);
 
 in_addr_t inet_addr (const char *);
 char *inet_ntoa (struct in_addr);
-int inet_pton (int, const char *, void *);
-const char *inet_ntop (int, const void *, char *, socklen_t);
+int inet_pton (int, const char *__restrict, void *__restrict);
+const char *inet_ntop (int, const void *__restrict, char *__restrict, socklen_t);
 
 int inet_aton (const char *, struct in_addr *); /* nonstandard but widely used */
 
diff --git a/include/dirent.h b/include/dirent.h
index c19f7d58..b6261595 100644
--- a/include/dirent.h
+++ b/include/dirent.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define __NEED_ino_t
 #define __NEED_off_t
 #ifdef _BSD_SOURCE
@@ -30,7 +36,7 @@ int            closedir(DIR *);
 DIR           *fdopendir(int);
 DIR           *opendir(const char *);
 struct dirent *readdir(DIR *);
-int            readdir_r(DIR *, struct dirent *, struct dirent **);
+int            readdir_r(DIR *__restrict, struct dirent *__restrict, struct dirent **__restrict);
 void           rewinddir(DIR *);
 void           seekdir(DIR *, long);
 long           telldir(DIR *);
diff --git a/include/dlfcn.h b/include/dlfcn.h
index e98c8ca6..2e7d0283 100644
--- a/include/dlfcn.h
+++ b/include/dlfcn.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define RTLD_LAZY   1
 #define RTLD_NOW    2
 #define RTLD_GLOBAL 256
@@ -16,7 +22,7 @@ extern "C" {
 int    dlclose(void *);
 char  *dlerror(void);
 void  *dlopen(const char *, int);
-void  *dlsym(void *, const char *);
+void  *dlsym(void *__restrict, const char *__restrict);
 
 #ifdef _GNU_SOURCE
 typedef struct {
diff --git a/include/glob.h b/include/glob.h
index 376baa71..c49a2dea 100644
--- a/include/glob.h
+++ b/include/glob.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define __NEED_size_t
 
 #include <bits/alltypes.h>
@@ -17,7 +23,7 @@ typedef struct {
 	void *__dummy2[5];
 } glob_t;
 
-int  glob(const char *, int, int (*)(const char *, int), glob_t *);
+int  glob(const char *__restrict, int, int (*)(const char *, int), glob_t *__restrict);
 void globfree(glob_t *);
 
 #define GLOB_ERR      0x01
diff --git a/include/iconv.h b/include/iconv.h
index f2ccaf8c..cef06f60 100644
--- a/include/iconv.h
+++ b/include/iconv.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define __NEED_size_t
 
 #include <bits/alltypes.h>
@@ -12,7 +18,7 @@ extern "C" {
 typedef void *iconv_t;
 
 iconv_t iconv_open(const char *, const char *);
-size_t iconv(iconv_t, char **, size_t *, char **, size_t *);
+size_t iconv(iconv_t, char **__restrict, size_t *__restrict, char **__restrict, size_t *__restrict);
 int iconv_close(iconv_t);
 
 #ifdef __cplusplus
diff --git a/include/inttypes.h b/include/inttypes.h
index 13ba6e0f..23acc5be 100644
--- a/include/inttypes.h
+++ b/include/inttypes.h
@@ -10,16 +10,22 @@ extern "C" {
 #define __NEED_wchar_t
 #include <bits/alltypes.h>
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 typedef struct { intmax_t quot, rem; } imaxdiv_t;
 
 intmax_t imaxabs(intmax_t);
 imaxdiv_t imaxdiv(intmax_t, intmax_t);
 
-intmax_t strtoimax(const char *, char **, int);
-uintmax_t strtoumax(const char *, char **, int);
+intmax_t strtoimax(const char *__restrict, char **__restrict, int);
+uintmax_t strtoumax(const char *__restrict, char **__restrict, int);
 
-intmax_t wcstoimax(const wchar_t *, wchar_t **, int);
-uintmax_t wcstoumax(const wchar_t *, wchar_t **, int);
+intmax_t wcstoimax(const wchar_t *__restrict, wchar_t **__restrict, int);
+uintmax_t wcstoumax(const wchar_t *__restrict, wchar_t **__restrict, int);
 
 #if !defined __cplusplus || defined __STDC_FORMAT_MACROS
 
diff --git a/include/monetary.h b/include/monetary.h
index df904eb0..11dabb23 100644
--- a/include/monetary.h
+++ b/include/monetary.h
@@ -5,14 +5,20 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define __NEED_ssize_t
 #define __NEED_size_t
 #define __NEED_locale_t
 
 #include <bits/alltypes.h>
 
-ssize_t strfmon(char *, size_t, const char *, ...);
-ssize_t strfmon_l(char *, size_t, locale_t, const char *, ...);
+ssize_t strfmon(char *__restrict, size_t, const char *__restrict, ...);
+ssize_t strfmon_l(char *__restrict, size_t, locale_t, const char *__restrict, ...);
 
 #ifdef __cplusplus
 }
diff --git a/include/mqueue.h b/include/mqueue.h
index 92e6ae5e..bd35842c 100644
--- a/include/mqueue.h
+++ b/include/mqueue.h
@@ -4,6 +4,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define __NEED_size_t
 #define __NEED_ssize_t
 #define __NEED_pthread_attr_t
@@ -23,8 +29,8 @@ int mq_notify(mqd_t, const struct sigevent *);
 mqd_t mq_open(const char *, int, ...);
 ssize_t mq_receive(mqd_t, char *, size_t, unsigned *);
 int mq_send(mqd_t, const char *, size_t, unsigned);
-int mq_setattr(mqd_t, const struct mq_attr *, struct mq_attr *);
-ssize_t mq_timedreceive(mqd_t, char *, size_t, unsigned *, const struct timespec *);
+int mq_setattr(mqd_t, const struct mq_attr *__restrict, struct mq_attr *__restrict);
+ssize_t mq_timedreceive(mqd_t, char *__restrict, size_t, unsigned *__restrict, const struct timespec *__restrict);
 int mq_timedsend(mqd_t, const char *, size_t, unsigned, const struct timespec *);
 int mq_unlink(const char *);
 
diff --git a/include/netdb.h b/include/netdb.h
index 42a4b682..d915d9d5 100644
--- a/include/netdb.h
+++ b/include/netdb.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #if defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
 #define __NEED_size_t
 #endif
@@ -55,9 +61,9 @@ struct addrinfo
 #define EAI_SYSTEM     -11
 #define EAI_OVERFLOW   -12
 
-int getaddrinfo (const char *, const char *, const struct addrinfo *, struct addrinfo **);
+int getaddrinfo (const char *__restrict, const char *__restrict, const struct addrinfo *__restrict, struct addrinfo **__restrict);
 void freeaddrinfo (struct addrinfo *);
-int getnameinfo (const struct sockaddr *, socklen_t, char *, socklen_t, char *, socklen_t, int);
+int getnameinfo (const struct sockaddr *__restrict, socklen_t, char *__restrict, socklen_t, char *__restrict, socklen_t, int);
 const char *gai_strerror(int);
 
 
diff --git a/include/pthread.h b/include/pthread.h
index d4ffb9ab..417156c8 100644
--- a/include/pthread.h
+++ b/include/pthread.h
@@ -4,6 +4,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define __NEED_time_t
 #define __NEED_clockid_t
 #define __NEED_struct_timespec
@@ -71,7 +77,7 @@ extern "C" {
 #define PTHREAD_BARRIER_SERIAL_THREAD (-1)
 
 
-int pthread_create(pthread_t *, const pthread_attr_t *, void *(*)(void *), void *);
+int pthread_create(pthread_t *__restrict, const pthread_attr_t *__restrict, void *(*)(void *), void *__restrict);
 int pthread_detach(pthread_t);
 void pthread_exit(void *);
 int pthread_join(pthread_t, void **);
@@ -91,29 +97,29 @@ int pthread_cancel(pthread_t);
 
 int pthread_once(pthread_once_t *, void (*)(void));
 
-int pthread_mutex_init(pthread_mutex_t *, const pthread_mutexattr_t *);
+int pthread_mutex_init(pthread_mutex_t *__restrict, const pthread_mutexattr_t *__restrict);
 int pthread_mutex_lock(pthread_mutex_t *);
 int pthread_mutex_unlock(pthread_mutex_t *);
 int pthread_mutex_trylock(pthread_mutex_t *);
-int pthread_mutex_timedlock(pthread_mutex_t *, const struct timespec *);
+int pthread_mutex_timedlock(pthread_mutex_t *__restrict, const struct timespec *__restrict);
 int pthread_mutex_destroy(pthread_mutex_t *);
 int pthread_mutex_consistent(pthread_mutex_t *);
 
-int pthread_cond_init(pthread_cond_t *, const pthread_condattr_t *);
+int pthread_cond_init(pthread_cond_t *__restrict, const pthread_condattr_t *__restrict);
 int pthread_cond_destroy(pthread_cond_t *);
-int pthread_cond_wait(pthread_cond_t *, pthread_mutex_t *);
-int pthread_cond_timedwait(pthread_cond_t *, pthread_mutex_t *, const struct timespec *);
+int pthread_cond_wait(pthread_cond_t *__restrict, pthread_mutex_t *__restrict);
+int pthread_cond_timedwait(pthread_cond_t *__restrict, pthread_mutex_t *__restrict, const struct timespec *__restrict);
 int pthread_cond_broadcast(pthread_cond_t *);
 int pthread_cond_signal(pthread_cond_t *);
 
-int pthread_rwlock_init(pthread_rwlock_t *, const pthread_rwlockattr_t *);
+int pthread_rwlock_init(pthread_rwlock_t *__restrict, const pthread_rwlockattr_t *__restrict);
 int pthread_rwlock_destroy(pthread_rwlock_t *);
 int pthread_rwlock_rdlock(pthread_rwlock_t *);
 int pthread_rwlock_tryrdlock(pthread_rwlock_t *);
-int pthread_rwlock_timedrdlock(pthread_rwlock_t *, const struct timespec *);
+int pthread_rwlock_timedrdlock(pthread_rwlock_t *__restrict, const struct timespec *__restrict);
 int pthread_rwlock_wrlock(pthread_rwlock_t *);
 int pthread_rwlock_trywrlock(pthread_rwlock_t *);
-int pthread_rwlock_timedwrlock(pthread_rwlock_t *, const struct timespec *);
+int pthread_rwlock_timedwrlock(pthread_rwlock_t *__restrict, const struct timespec *__restrict);
 int pthread_rwlock_unlock(pthread_rwlock_t *);
 
 int pthread_spin_init(pthread_spinlock_t *, int);
@@ -122,7 +128,7 @@ int pthread_spin_lock(pthread_spinlock_t *);
 int pthread_spin_trylock(pthread_spinlock_t *);
 int pthread_spin_unlock(pthread_spinlock_t *);
 
-int pthread_barrier_init(pthread_barrier_t *, const pthread_barrierattr_t *, unsigned);
+int pthread_barrier_init(pthread_barrier_t *__restrict, const pthread_barrierattr_t *__restrict, unsigned);
 int pthread_barrier_destroy(pthread_barrier_t *);
 int pthread_barrier_wait(pthread_barrier_t *);
 
@@ -134,29 +140,29 @@ int pthread_setspecific(pthread_key_t, const void *);
 int pthread_attr_init(pthread_attr_t *);
 int pthread_attr_destroy(pthread_attr_t *);
 
-int pthread_attr_getguardsize(const pthread_attr_t *, size_t *);
+int pthread_attr_getguardsize(const pthread_attr_t *__restrict, size_t *__restrict);
 int pthread_attr_setguardsize(pthread_attr_t *, size_t);
-int pthread_attr_getstacksize(const pthread_attr_t *, size_t *);
+int pthread_attr_getstacksize(const pthread_attr_t *__restrict, size_t *__restrict);
 int pthread_attr_setstacksize(pthread_attr_t *, size_t);
 int pthread_attr_getdetachstate(const pthread_attr_t *, int *);
 int pthread_attr_setdetachstate(pthread_attr_t *, int);
-int pthread_attr_getstack(const pthread_attr_t *, void **, size_t *);
+int pthread_attr_getstack(const pthread_attr_t *__restrict, void **__restrict, size_t *__restrict);
 int pthread_attr_setstack(pthread_attr_t *, void *, size_t);
-int pthread_attr_getscope(const pthread_attr_t *, int *);
+int pthread_attr_getscope(const pthread_attr_t *__restrict, int *__restrict);
 int pthread_attr_setscope(pthread_attr_t *, int);
-int pthread_attr_getschedpolicy(const pthread_attr_t *, int *);
+int pthread_attr_getschedpolicy(const pthread_attr_t *__restrict, int *__restrict);
 int pthread_attr_setschedpolicy(pthread_attr_t *, int);
-int pthread_attr_getschedparam(const pthread_attr_t *, struct sched_param *);
-int pthread_attr_setschedparam(pthread_attr_t *, const struct sched_param *);
-int pthread_attr_getinheritsched(const pthread_attr_t *, int *);
+int pthread_attr_getschedparam(const pthread_attr_t *__restrict, struct sched_param *__restrict);
+int pthread_attr_setschedparam(pthread_attr_t *__restrict, const struct sched_param *__restrict);
+int pthread_attr_getinheritsched(const pthread_attr_t *__restrict, int *__restrict);
 int pthread_attr_setinheritsched(pthread_attr_t *, int);
 
 int pthread_mutexattr_destroy(pthread_mutexattr_t *);
-int pthread_mutexattr_getprioceiling(const pthread_mutexattr_t *, int *);
-int pthread_mutexattr_getprotocol(const pthread_mutexattr_t *, int *);
-int pthread_mutexattr_getpshared(const pthread_mutexattr_t *, int *);
-int pthread_mutexattr_getrobust(const pthread_mutexattr_t *, int *);
-int pthread_mutexattr_gettype(const pthread_mutexattr_t *, int *);
+int pthread_mutexattr_getprioceiling(const pthread_mutexattr_t *__restrict, int *__restrict);
+int pthread_mutexattr_getprotocol(const pthread_mutexattr_t *__restrict, int *__restrict);
+int pthread_mutexattr_getpshared(const pthread_mutexattr_t *__restrict, int *__restrict);
+int pthread_mutexattr_getrobust(const pthread_mutexattr_t *__restrict, int *__restrict);
+int pthread_mutexattr_gettype(const pthread_mutexattr_t *__restrict, int *__restrict);
 int pthread_mutexattr_init(pthread_mutexattr_t *);
 int pthread_mutexattr_setprioceiling(pthread_mutexattr_t *, int);
 int pthread_mutexattr_setprotocol(pthread_mutexattr_t *, int);
@@ -168,16 +174,16 @@ int pthread_condattr_init(pthread_condattr_t *);
 int pthread_condattr_destroy(pthread_condattr_t *);
 int pthread_condattr_setclock(pthread_condattr_t *, clockid_t);
 int pthread_condattr_setpshared(pthread_condattr_t *, int);
-int pthread_condattr_getclock(const pthread_condattr_t *, clockid_t *);
-int pthread_condattr_getpshared(const pthread_condattr_t *, int *);
+int pthread_condattr_getclock(const pthread_condattr_t *__restrict, clockid_t *__restrict);
+int pthread_condattr_getpshared(const pthread_condattr_t *__restrict, int *__restrict);
 
 int pthread_rwlockattr_init(pthread_rwlockattr_t *);
 int pthread_rwlockattr_destroy(pthread_rwlockattr_t *);
 int pthread_rwlockattr_setpshared(pthread_rwlockattr_t *, int);
-int pthread_rwlockattr_getpshared(const pthread_rwlockattr_t *, int *);
+int pthread_rwlockattr_getpshared(const pthread_rwlockattr_t *__restrict, int *__restrict);
 
 int pthread_barrierattr_destroy(pthread_barrierattr_t *);
-int pthread_barrierattr_getpshared(const pthread_barrierattr_t *, int *);
+int pthread_barrierattr_getpshared(const pthread_barrierattr_t *__restrict, int *__restrict);
 int pthread_barrierattr_init(pthread_barrierattr_t *);
 int pthread_barrierattr_setpshared(pthread_barrierattr_t *, int);
 
diff --git a/include/regex.h b/include/regex.h
index d57208a5..b7167b87 100644
--- a/include/regex.h
+++ b/include/regex.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define __NEED_size_t
 
 #include <bits/alltypes.h>
@@ -47,11 +53,11 @@ typedef struct {
 
 #define REG_ENOSYS      -1
 
-int regcomp(regex_t *, const char *, int);
-int regexec(const regex_t *, const char *, size_t, regmatch_t [], int);
+int regcomp(regex_t *__restrict, const char *__restrict, int);
+int regexec(const regex_t *__restrict, const char *__restrict, size_t, regmatch_t *__restrict, int);
 void regfree(regex_t *);
 
-size_t regerror(int, const regex_t *, char *, size_t);
+size_t regerror(int, const regex_t *__restrict, char *__restrict, size_t);
 
 #ifdef __cplusplus
 }
diff --git a/include/search.h b/include/search.h
index 7c4fc583..680eee75 100644
--- a/include/search.h
+++ b/include/search.h
@@ -5,6 +5,13 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
+
 #define __NEED_size_t
 #include <bits/alltypes.h>
 
@@ -28,7 +35,7 @@ void *lsearch(const void *, void *, size_t *, size_t,
 void *lfind(const void *, const void *, size_t *, size_t,
 	int (*)(const void *, const void *));
 
-void *tdelete(const void *, void **, int(*)(const void *, const void *));
+void *tdelete(const void *__restrict, void **__restrict, int(*)(const void *, const void *));
 void *tfind(const void *, void *const *, int(*)(const void *, const void *));
 void *tsearch(const void *, void **, int (*)(const void *, const void *));
 void twalk(const void *, void (*)(const void *, VISIT, int));
diff --git a/include/semaphore.h b/include/semaphore.h
index 2e9b8100..724957fb 100644
--- a/include/semaphore.h
+++ b/include/semaphore.h
@@ -4,6 +4,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define __NEED_time_t
 #define __NEED_struct_timespec
 #include <bits/alltypes.h>
@@ -18,11 +24,11 @@ typedef struct {
 
 int    sem_close(sem_t *);
 int    sem_destroy(sem_t *);
-int    sem_getvalue(sem_t *, int *);
+int    sem_getvalue(sem_t *__restrict, int *__restrict);
 int    sem_init(sem_t *, int, unsigned);
 sem_t *sem_open(const char *, int, ...);
 int    sem_post(sem_t *);
-int    sem_timedwait(sem_t *, const struct timespec *);
+int    sem_timedwait(sem_t *__restrict, const struct timespec *__restrict);
 int    sem_trywait(sem_t *);
 int    sem_unlink(const char *);
 int    sem_wait(sem_t *);
diff --git a/include/signal.h b/include/signal.h
index d4856a89..e0dae192 100644
--- a/include/signal.h
+++ b/include/signal.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #if defined(_POSIX_SOURCE) || defined(_POSIX_C_SOURCE) \
  || defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) \
  || defined(_BSD_SOURCE)
@@ -165,16 +171,16 @@ int sigaddset(sigset_t *, int);
 int sigdelset(sigset_t *, int);
 int sigismember(const sigset_t *, int);
 
-int sigprocmask(int, const sigset_t *, sigset_t *);
+int sigprocmask(int, const sigset_t *__restrict, sigset_t *__restrict);
 int sigsuspend(const sigset_t *);
-int sigaction(int, const struct sigaction *, struct sigaction *);
+int sigaction(int, const struct sigaction *__restrict, struct sigaction *__restrict);
 int sigpending(sigset_t *);
-int sigwait(const sigset_t *, int *);
-int sigwaitinfo(const sigset_t *, siginfo_t *);
-int sigtimedwait(const sigset_t *, siginfo_t *, const struct timespec *);
+int sigwait(const sigset_t *__restrict, int *__restrict);
+int sigwaitinfo(const sigset_t *__restrict, siginfo_t *__restrict);
+int sigtimedwait(const sigset_t *__restrict, siginfo_t *__restrict, const struct timespec *__restrict);
 int sigqueue(pid_t, int, const union sigval);
 
-int pthread_sigmask(int, const sigset_t *, sigset_t *);
+int pthread_sigmask(int, const sigset_t *__restrict, sigset_t *__restrict);
 int pthread_kill(pthread_t, int);
 
 void psiginfo(const siginfo_t *, const char *);
@@ -184,7 +190,7 @@ void psignal(int, const char *);
 
 #if defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE)
 int killpg(pid_t, int);
-int sigaltstack(const stack_t *, stack_t *);
+int sigaltstack(const stack_t *__restrict, stack_t *__restrict);
 int sighold(int);
 int sigignore(int);
 int siginterrupt(int, int);
diff --git a/include/spawn.h b/include/spawn.h
index 99ec6f1d..c934d423 100644
--- a/include/spawn.h
+++ b/include/spawn.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define __NEED_mode_t
 #define __NEED_pid_t
 #define __NEED_sigset_t
@@ -33,30 +39,30 @@ typedef struct {
 	int __pad[16];
 } posix_spawn_file_actions_t;
 
-int posix_spawn(pid_t *, const char *, const posix_spawn_file_actions_t *,
-	const posix_spawnattr_t *, char *const [], char *const []);
-int posix_spawnp(pid_t *, const char *, const posix_spawn_file_actions_t *,
-	const posix_spawnattr_t *, char *const [], char *const []);
+int posix_spawn(pid_t *__restrict, const char *__restrict, const posix_spawn_file_actions_t *,
+	const posix_spawnattr_t *__restrict, char *const *__restrict, char *const *__restrict);
+int posix_spawnp(pid_t *__restrict, const char *__restrict, const posix_spawn_file_actions_t *,
+	const posix_spawnattr_t *__restrict, char *const *__restrict, char *const *__restrict);
 
 int posix_spawnattr_init(posix_spawnattr_t *);
 int posix_spawnattr_destroy(posix_spawnattr_t *);
 
 int posix_spawnattr_setflags(posix_spawnattr_t *, short);
-int posix_spawnattr_getflags(const posix_spawnattr_t *, short *);
+int posix_spawnattr_getflags(const posix_spawnattr_t *__restrict, short *__restrict);
 
 int posix_spawnattr_setpgroup(posix_spawnattr_t *, pid_t);
-int posix_spawnattr_getpgroup(const posix_spawnattr_t *, pid_t *);
+int posix_spawnattr_getpgroup(const posix_spawnattr_t *__restrict, pid_t *__restrict);
 
-int posix_spawnattr_setsigmask(posix_spawnattr_t *, const sigset_t *);
-int posix_spawnattr_getsigmask(const posix_spawnattr_t *, sigset_t *);
+int posix_spawnattr_setsigmask(posix_spawnattr_t *__restrict, const sigset_t *__restrict);
+int posix_spawnattr_getsigmask(const posix_spawnattr_t *__restrict, sigset_t *__restrict);
 
-int posix_spawnattr_setsigdefault(posix_spawnattr_t *, const sigset_t *);
-int posix_spawnattr_getsigdefault(const posix_spawnattr_t *, sigset_t *);
+int posix_spawnattr_setsigdefault(posix_spawnattr_t *__restrict, const sigset_t *__restrict);
+int posix_spawnattr_getsigdefault(const posix_spawnattr_t *__restrict, sigset_t *__restrict);
 
 int posix_spawn_file_actions_init(posix_spawn_file_actions_t *);
 int posix_spawn_file_actions_destroy(posix_spawn_file_actions_t *);
 
-int posix_spawn_file_actions_addopen(posix_spawn_file_actions_t *, int, const char *, int, mode_t);
+int posix_spawn_file_actions_addopen(posix_spawn_file_actions_t *__restrict, int, const char *__restrict, int, mode_t);
 int posix_spawn_file_actions_addclose(posix_spawn_file_actions_t *, int);
 int posix_spawn_file_actions_adddup2(posix_spawn_file_actions_t *, int, int);
 
diff --git a/include/stdio.h b/include/stdio.h
index 9aa2f782..7d3130e2 100644
--- a/include/stdio.h
+++ b/include/stdio.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define __NEED_FILE
 #define __NEED_va_list
 #define __NEED_size_t
@@ -58,8 +64,8 @@ extern FILE *const stderr;
 #define stdout (stdout)
 #define stderr (stderr)
 
-FILE *fopen(const char *, const char *);
-FILE *freopen(const char *, const char *, FILE *);
+FILE *fopen(const char *__restrict, const char *__restrict);
+FILE *freopen(const char *__restrict, const char *__restrict, FILE *__restrict);
 int fclose(FILE *);
 
 int remove(const char *);
@@ -74,11 +80,11 @@ int fseek(FILE *, long, int);
 long ftell(FILE *);
 void rewind(FILE *);
 
-int fgetpos(FILE *, fpos_t *);
+int fgetpos(FILE *__restrict, fpos_t *__restrict);
 int fsetpos(FILE *, const fpos_t *);
 
-size_t fread(void *, size_t, size_t, FILE *);
-size_t fwrite(const void *, size_t, size_t, FILE *);
+size_t fread(void *__restrict, size_t, size_t, FILE *__restrict);
+size_t fwrite(const void *__restrict, size_t, size_t, FILE *__restrict);
 
 int fgetc(FILE *);
 int getc(FILE *);
@@ -89,35 +95,35 @@ int fputc(int, FILE *);
 int putc(int, FILE *);
 int putchar(int);
 
-char *fgets(char *, int, FILE *);
+char *fgets(char *__restrict, int, FILE *__restrict);
 #if __STDC_VERSION__ < 201112L
 char *gets(char *);
 #endif
 
-int fputs(const char *, FILE *);
+int fputs(const char *__restrict, FILE *__restrict);
 int puts(const char *);
 
-int printf(const char *, ...);
-int fprintf(FILE *, const char *, ...);
-int sprintf(char *, const char *, ...);
-int snprintf(char *, size_t, const char *, ...);
+int printf(const char *__restrict, ...);
+int fprintf(FILE *__restrict, const char *__restrict, ...);
+int sprintf(char *__restrict, const char *__restrict, ...);
+int snprintf(char *__restrict, size_t, const char *__restrict, ...);
 
-int vprintf(const char *, va_list);
-int vfprintf(FILE *, const char *, va_list);
-int vsprintf(char *, const char *, va_list);
-int vsnprintf(char *, size_t, const char *, va_list);
+int vprintf(const char *__restrict, va_list);
+int vfprintf(FILE *__restrict, const char *__restrict, va_list);
+int vsprintf(char *__restrict, const char *__restrict, va_list);
+int vsnprintf(char *__restrict, size_t, const char *__restrict, va_list);
 
-int scanf(const char *, ...);
-int fscanf(FILE *, const char *, ...);
-int sscanf(const char *, const char *, ...);
-int vscanf(const char *, va_list);
-int vfscanf(FILE *, const char *, va_list);
-int vsscanf(const char *, const char *, va_list);
+int scanf(const char *__restrict, ...);
+int fscanf(FILE *__restrict, const char *__restrict, ...);
+int sscanf(const char *__restrict, const char *__restrict, ...);
+int vscanf(const char *__restrict, va_list);
+int vfscanf(FILE *__restrict, const char *__restrict, va_list);
+int vsscanf(const char *__restrict, const char *__restrict, va_list);
 
 void perror(const char *);
 
-int setvbuf(FILE *, char *, int, size_t);
-void setbuf(FILE *, char *);
+int setvbuf(FILE *__restrict, char *__restrict, int, size_t);
+void setbuf(FILE *__restrict, char *__restrict);
 
 char *tmpnam(char *);
 FILE *tmpfile(void);
@@ -125,7 +131,7 @@ FILE *tmpfile(void);
 #if defined(_POSIX_SOURCE) || defined(_POSIX_C_SOURCE) \
  || defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) \
  || defined(_BSD_SOURCE)
-FILE *fmemopen(void *, size_t, const char *);
+FILE *fmemopen(void *__restrict, size_t, const char *__restrict);
 FILE *open_memstream(char **, size_t *);
 FILE *fdopen(int, const char *);
 FILE *popen(const char *, const char *);
@@ -133,8 +139,8 @@ int pclose(FILE *);
 int fileno(FILE *);
 int fseeko(FILE *, off_t, int);
 off_t ftello(FILE *);
-int dprintf(int, const char *, ...);
-int vdprintf(int, const char *, va_list);
+int dprintf(int, const char *__restrict, ...);
+int vdprintf(int, const char *__restrict, va_list);
 void flockfile(FILE *);
 int ftrylockfile(FILE *);
 void funlockfile(FILE *);
@@ -142,8 +148,8 @@ int getc_unlocked(FILE *);
 int getchar_unlocked(void);
 int putc_unlocked(int, FILE *);
 int putchar_unlocked(int);
-ssize_t getdelim(char **, size_t *, int, FILE *);
-ssize_t getline(char **, size_t *, FILE *);
+ssize_t getdelim(char **__restrict, size_t *__restrict, int, FILE *__restrict);
+ssize_t getline(char **__restrict, size_t *__restrict, FILE *__restrict);
 int renameat(int, const char *, int, const char *);
 char *ctermid(char *);
 #define L_ctermid 20
diff --git a/include/stdlib.h b/include/stdlib.h
index 1749cb3b..14cc71bb 100644
--- a/include/stdlib.h
+++ b/include/stdlib.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #undef NULL
 #ifdef __cplusplus
 #define NULL 0
@@ -22,14 +28,14 @@ long atol (const char *);
 long long atoll (const char *);
 double atof (const char *);
 
-float strtof (const char *, char **);
-double strtod (const char *, char **);
-long double strtold (const char *, char **);
+float strtof (const char *__restrict, char **__restrict);
+double strtod (const char *__restrict, char **__restrict);
+long double strtold (const char *__restrict, char **__restrict);
 
-long strtol (const char *, char **, int);
-unsigned long strtoul (const char *, char **, int);
-long long strtoll (const char *, char **, int);
-unsigned long long strtoull (const char *, char **, int);
+long strtol (const char *__restrict, char **__restrict, int);
+unsigned long strtoul (const char *__restrict, char **__restrict, int);
+long long strtoll (const char *__restrict, char **__restrict, int);
+unsigned long long strtoull (const char *__restrict, char **__restrict, int);
 
 int rand (void);
 void srand (unsigned);
@@ -67,10 +73,10 @@ ldiv_t ldiv (long, long);
 lldiv_t lldiv (long long, long long);
 
 int mblen (const char *, size_t);
-int mbtowc (wchar_t *, const char *, size_t);
+int mbtowc (wchar_t *__restrict, const char *__restrict, size_t);
 int wctomb (char *, wchar_t);
-size_t mbstowcs (wchar_t *, const char *, size_t);
-size_t wcstombs (char *, const wchar_t *, size_t);
+size_t mbstowcs (wchar_t *__restrict, const char *__restrict, size_t);
+size_t wcstombs (char *__restrict, const wchar_t *__restrict, size_t);
 
 #define EXIT_FAILURE 1
 #define EXIT_SUCCESS 0
@@ -108,7 +114,7 @@ int rand_r (unsigned *);
 
 #if defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) \
  || defined(_BSD_SOURCE)
-char *realpath (const char *, char *);
+char *realpath (const char *__restrict, char *__restrict);
 long int random (void);
 void srandom (unsigned int);
 char *initstate (unsigned int, char *, size_t);
diff --git a/include/string.h b/include/string.h
index 24cb1ca3..f96f71ee 100644
--- a/include/string.h
+++ b/include/string.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #undef NULL
 #ifdef __cplusplus
 #define NULL 0
@@ -21,23 +27,23 @@ extern "C" {
 
 #include <bits/alltypes.h>
 
-void *memcpy (void *, const void *, size_t);
+void *memcpy (void *__restrict, const void *__restrict, size_t);
 void *memmove (void *, const void *, size_t);
 void *memset (void *, int, size_t);
 int memcmp (const void *, const void *, size_t);
 void *memchr (const void *, int, size_t);
 
-char *strcpy (char *, const char *);
-char *strncpy (char *, const char *, size_t);
+char *strcpy (char *__restrict, const char *__restrict);
+char *strncpy (char *__restrict, const char *__restrict, size_t);
 
-char *strcat (char *, const char *);
-char *strncat (char *, const char *, size_t);
+char *strcat (char *__restrict, const char *__restrict);
+char *strncat (char *__restrict, const char *__restrict, size_t);
 
 int strcmp (const char *, const char *);
 int strncmp (const char *, const char *, size_t);
 
 int strcoll (const char *, const char *);
-size_t strxfrm (char *, const char *, size_t);
+size_t strxfrm (char *__restrict, const char *__restrict, size_t);
 
 char *strchr (const char *, int);
 char *strrchr (const char *, int);
@@ -46,7 +52,7 @@ size_t strcspn (const char *, const char *);
 size_t strspn (const char *, const char *);
 char *strpbrk (const char *, const char *);
 char *strstr (const char *, const char *);
-char *strtok (char *, const char *);
+char *strtok (char *__restrict, const char *__restrict);
 
 size_t strlen (const char *);
 
@@ -59,22 +65,22 @@ char *strerror (int);
 #if defined(_POSIX_SOURCE) || defined(_POSIX_C_SOURCE) \
  || defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) \
  || defined(_BSD_SOURCE)
-char *strtok_r (char *, const char *, char **);
+char *strtok_r (char *__restrict, const char *__restrict, char **__restrict);
 int strerror_r (int, char *, size_t);
-char *stpcpy(char *, const char *);
-char *stpncpy(char *, const char *, size_t);
+char *stpcpy(char *__restrict, const char *__restrict);
+char *stpncpy(char *__restrict, const char *__restrict, size_t);
 size_t strnlen (const char *, size_t);
 char *strdup (const char *);
 char *strndup (const char *, size_t);
 char *strsignal(int);
 char *strerror_l (int, locale_t);
 int strcoll_l (const char *, const char *, locale_t);
-size_t strxfrm_l (char *, const char *, size_t, locale_t);
+size_t strxfrm_l (char *__restrict, const char *__restrict, size_t, locale_t);
 #endif
 
 #if defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) \
  || defined(_BSD_SOURCE)
-void *memccpy (void *, const void *, int, size_t);
+void *memccpy (void *__restrict, const void *__restrict, int, size_t);
 #endif
 
 #ifdef _BSD_SOURCE
diff --git a/include/sys/select.h b/include/sys/select.h
index 47d195f4..dd4176dd 100644
--- a/include/sys/select.h
+++ b/include/sys/select.h
@@ -4,6 +4,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define __NEED_size_t
 #define __NEED_time_t
 #define __NEED_suseconds_t
@@ -27,8 +33,8 @@ typedef struct
 #define FD_CLR(d, s)   ((s)->fds_bits[(d)/(8*sizeof(long))] &= ~(1UL<<((d)%(8*sizeof(long)))))
 #define FD_ISSET(d, s) !!((s)->fds_bits[(d)/(8*sizeof(long))] & (1UL<<((d)%(8*sizeof(long)))))
 
-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 *);
+int select (int, fd_set *__restrict, fd_set *__restrict, fd_set *__restrict, struct timeval *__restrict);
+int pselect (int, fd_set *__restrict, fd_set *__restrict, fd_set *__restrict, const struct timespec *__restrict, const sigset_t *__restrict);
 
 
 #ifdef __cplusplus
diff --git a/include/sys/socket.h b/include/sys/socket.h
index a384ca12..7024d232 100644
--- a/include/sys/socket.h
+++ b/include/sys/socket.h
@@ -4,6 +4,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define __NEED_socklen_t
 #define __NEED_sa_family_t
 #define __NEED_size_t
@@ -232,19 +238,19 @@ int shutdown (int, int);
 int bind (int, const struct sockaddr *, socklen_t);
 int connect (int, const struct sockaddr *, socklen_t);
 int listen (int, int);
-int accept (int, struct sockaddr *, socklen_t *);
+int accept (int, struct sockaddr *__restrict, socklen_t *__restrict);
 
-int getsockname (int, struct sockaddr *, socklen_t *);
-int getpeername (int, struct sockaddr *, socklen_t *);
+int getsockname (int, struct sockaddr *__restrict, socklen_t *__restrict);
+int getpeername (int, struct sockaddr *__restrict, socklen_t *__restrict);
 
 ssize_t send (int, const void *, size_t, int);
 ssize_t recv (int, void *, size_t, int);
 ssize_t sendto (int, const void *, size_t, int, const struct sockaddr *, socklen_t);
-ssize_t recvfrom (int, void *, size_t, int, struct sockaddr *, socklen_t *);
+ssize_t recvfrom (int, void *__restrict, size_t, int, struct sockaddr *__restrict, socklen_t *__restrict);
 ssize_t sendmsg (int, const struct msghdr *, int);
 ssize_t recvmsg (int, struct msghdr *, int);
 
-int getsockopt (int, int, int, void *, socklen_t *);
+int getsockopt (int, int, int, void *__restrict, socklen_t *__restrict);
 int setsockopt (int, int, int, const void *, socklen_t);
 
 int sockatmark (int);
diff --git a/include/sys/stat.h b/include/sys/stat.h
index 2a7ce233..e16a9682 100644
--- a/include/sys/stat.h
+++ b/include/sys/stat.h
@@ -4,6 +4,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define __NEED_dev_t
 #define __NEED_ino_t
 #define __NEED_mode_t
@@ -68,10 +74,10 @@ extern "C" {
 #define UTIME_NOW  0x3fffffff
 #define UTIME_OMIT 0x3ffffffe
 
-int stat(const char *, struct stat *);
+int stat(const char *__restrict, struct stat *__restrict);
 int fstat(int, struct stat *);
-int lstat(const char *, struct stat *);
-int fstatat(int, const char *, struct stat *, int);
+int lstat(const char *__restrict, struct stat *__restrict);
+int fstatat(int, const char *__restrict, struct stat *__restrict, int);
 int chmod(const char *, mode_t);
 int fchmod(int, mode_t);
 int fchmodat(int, const char *, mode_t, int);
diff --git a/include/sys/statvfs.h b/include/sys/statvfs.h
index 0a3ac9e0..be41c287 100644
--- a/include/sys/statvfs.h
+++ b/include/sys/statvfs.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define __NEED_fsblkcnt_t
 #define __NEED_fsfilcnt_t
 #include <bits/alltypes.h>
@@ -26,7 +32,7 @@ struct statvfs {
 	int __reserved[6];
 };
 
-int statvfs (const char *, struct statvfs *);
+int statvfs (const char *__restrict, struct statvfs *__restrict);
 int fstatvfs (int, struct statvfs *);
 
 #define ST_RDONLY 1
diff --git a/include/sys/time.h b/include/sys/time.h
index 144dd230..bf026432 100644
--- a/include/sys/time.h
+++ b/include/sys/time.h
@@ -4,9 +4,15 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #include <sys/select.h>
 
-int gettimeofday (struct timeval *, void *);
+int gettimeofday (struct timeval *__restrict, void *__restrict);
 
 #if defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) \
  || defined(_BSD_SOURCE)
@@ -22,7 +28,7 @@ struct itimerval
 };
 
 int getitimer (int, struct itimerval *);
-int setitimer (int, const struct itimerval *, struct itimerval *);
+int setitimer (int, const struct itimerval *__restrict, struct itimerval *__restrict);
 int utimes (const char *, const struct timeval [2]);
 
 #endif
diff --git a/include/time.h b/include/time.h
index 3cc0d28a..f24789e4 100644
--- a/include/time.h
+++ b/include/time.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #undef NULL
 #ifdef __cplusplus
 #define NULL 0
@@ -48,7 +54,7 @@ clock_t clock (void);
 time_t time (time_t *);
 double difftime (time_t, time_t);
 time_t mktime (struct tm *);
-size_t strftime (char *, size_t, const char *, const struct tm *);
+size_t strftime (char *__restrict, size_t, const char *__restrict, const struct tm *__restrict);
 struct tm *gmtime (const time_t *);
 struct tm *localtime (const time_t *);
 char *asctime (const struct tm *);
@@ -61,11 +67,11 @@ char *ctime (const time_t *);
  || defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE) \
  || defined(_BSD_SOURCE)
 
-size_t strftime_l (char *, size_t, const char *, const struct tm *, locale_t);
+size_t strftime_l (char *  __restrict, size_t, const char *  __restrict, const struct tm *  __restrict, locale_t);
 
-struct tm *gmtime_r (const time_t *, struct tm *);
-struct tm *localtime_r (const time_t *, struct tm *);
-char *asctime_r (const struct tm *, char *);
+struct tm *gmtime_r (const time_t *__restrict, struct tm *__restrict);
+struct tm *localtime_r (const time_t *__restrict, struct tm *__restrict);
+char *asctime_r (const struct tm *__restrict, char *__restrict);
 char *ctime_r (const time_t *, char *);
 
 void tzset (void);
@@ -91,9 +97,9 @@ int clock_nanosleep (clockid_t, int, const struct timespec *, struct timespec *)
 int clock_getcpuclockid (pid_t, clockid_t *);
 
 struct sigevent;
-int timer_create (clockid_t, struct sigevent *, timer_t *);
+int timer_create (clockid_t, struct sigevent *__restrict, timer_t *__restrict);
 int timer_delete (timer_t);
-int timer_settime (timer_t, int, const struct itimerspec *, struct itimerspec *);
+int timer_settime (timer_t, int, const struct itimerspec *__restrict, struct itimerspec *__restrict);
 int timer_gettime (timer_t, struct itimerspec *);
 int timer_getoverrun (timer_t);
 
@@ -101,7 +107,7 @@ int timer_getoverrun (timer_t);
 
 
 #if defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE)
-char *strptime (const char *, const char *, struct tm *);
+char *strptime (const char *__restrict, const char *__restrict, struct tm *__restrict);
 extern int daylight;
 extern long timezone;
 extern char *tzname[2];
diff --git a/include/unistd.h b/include/unistd.h
index 12d153b8..ecb23f81 100644
--- a/include/unistd.h
+++ b/include/unistd.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define STDIN_FILENO  0
 #define STDOUT_FILENO 1
 #define STDERR_FILENO 2
@@ -52,8 +58,8 @@ int link(const char *, const char *);
 int linkat(int, const char *, int, const char *, int);
 int symlink(const char *, const char *);
 int symlinkat(const char *, int, const char *);
-ssize_t readlink(const char *, char *, size_t);
-ssize_t readlinkat(int, const char *, char *, size_t);
+ssize_t readlink(const char *__restrict, char *__restrict, size_t);
+ssize_t readlinkat(int, const char *__restrict, char *__restrict, size_t);
 int unlink(const char *);
 int unlinkat(int, const char *, int);
 int rmdir(const char *);
@@ -141,7 +147,7 @@ void sync(void);
 pid_t setpgrp(void);
 char *crypt(const char *, const char *);
 void encrypt(char *, int);
-void swab(const void *, void *, ssize_t);
+void swab(const void *__restrict, void *__restrict, ssize_t);
 #endif
 
 #if defined(_GNU_SOURCE) || defined(_BSD_SOURCE) \
diff --git a/include/wchar.h b/include/wchar.h
index 12ddd4f4..b1c6b7fa 100644
--- a/include/wchar.h
+++ b/include/wchar.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define __NEED_FILE
 #define __NEED_va_list
 #define __NEED_size_t
@@ -39,17 +45,17 @@ typedef struct
 	unsigned __opaque1, __opaque2;
 } mbstate_t;
 
-wchar_t *wcscpy (wchar_t *, const wchar_t *);
-wchar_t *wcsncpy (wchar_t *, const wchar_t *, size_t);
+wchar_t *wcscpy (wchar_t *__restrict, const wchar_t *__restrict);
+wchar_t *wcsncpy (wchar_t *__restrict, const wchar_t *__restrict, size_t);
 
-wchar_t *wcscat (wchar_t *, const wchar_t *);
-wchar_t *wcsncat (wchar_t *, const wchar_t *, size_t);
+wchar_t *wcscat (wchar_t *__restrict, const wchar_t *__restrict);
+wchar_t *wcsncat (wchar_t *__restrict, const wchar_t *__restrict, size_t);
 
 int wcscmp (const wchar_t *, const wchar_t *);
 int wcsncmp (const wchar_t *, const wchar_t *, size_t);
 
 int wcscoll(const wchar_t *, const wchar_t *);
-size_t wcsxfrm (wchar_t *, const wchar_t *, size_t n);
+size_t wcsxfrm (wchar_t *__restrict, const wchar_t *__restrict, size_t n);
 
 wchar_t *wcschr (const wchar_t *, wchar_t);
 wchar_t *wcsrchr (const wchar_t *, wchar_t);
@@ -58,16 +64,16 @@ size_t wcscspn (const wchar_t *, const wchar_t *);
 size_t wcsspn (const wchar_t *, const wchar_t *);
 wchar_t *wcspbrk (const wchar_t *, const wchar_t *);
 
-wchar_t *wcstok (wchar_t *, const wchar_t *, wchar_t **);
+wchar_t *wcstok (wchar_t *__restrict, const wchar_t *__restrict, wchar_t **__restrict);
 
 size_t wcslen (const wchar_t *);
 
-wchar_t *wcsstr (const wchar_t *, const wchar_t *);
+wchar_t *wcsstr (const wchar_t *__restrict, const wchar_t *__restrict);
 wchar_t *wcswcs (const wchar_t *, const wchar_t *);
 
 wchar_t *wmemchr (const wchar_t *, wchar_t, size_t);
 int wmemcmp (const wchar_t *, const wchar_t *, size_t);
-wchar_t *wmemcpy (wchar_t *, const wchar_t *, size_t);
+wchar_t *wmemcpy (wchar_t *__restrict, const wchar_t *__restrict, size_t);
 wchar_t *wmemmove (wchar_t *, const wchar_t *, size_t);
 wchar_t *wmemset (wchar_t *, wchar_t, size_t);
 
@@ -75,44 +81,44 @@ wint_t btowc (int);
 int wctob (wint_t);
 
 int mbsinit (const mbstate_t *);
-size_t mbrtowc (wchar_t *, const char *, size_t, mbstate_t *);
-size_t wcrtomb (char *, wchar_t, mbstate_t *);
+size_t mbrtowc (wchar_t *__restrict, const char *__restrict, size_t, mbstate_t *__restrict);
+size_t wcrtomb (char *__restrict, wchar_t, mbstate_t *__restrict);
 
-size_t mbrlen (const char *, size_t, mbstate_t *);
+size_t mbrlen (const char *__restrict, size_t, mbstate_t *__restrict);
 
-size_t mbsrtowcs (wchar_t *, const char **, size_t, mbstate_t *);
-size_t wcsrtombs (char *, const wchar_t **, size_t, mbstate_t *);
+size_t mbsrtowcs (wchar_t *__restrict, const char **__restrict, size_t, mbstate_t *__restrict);
+size_t wcsrtombs (char *__restrict, const wchar_t **__restrict, size_t, mbstate_t *__restrict);
 
-float wcstof (const wchar_t *, wchar_t **);
-double wcstod (const wchar_t *, wchar_t **);
-long double wcstold (const wchar_t *, wchar_t **);
+float wcstof (const wchar_t *__restrict, wchar_t **__restrict);
+double wcstod (const wchar_t *__restrict, wchar_t **__restrict);
+long double wcstold (const wchar_t *__restrict, wchar_t **__restrict);
 
-long wcstol (const wchar_t *, wchar_t **, int);
-unsigned long wcstoul (const wchar_t *, wchar_t **, int);
+long wcstol (const wchar_t *__restrict, wchar_t **__restrict, int);
+unsigned long wcstoul (const wchar_t *__restrict, wchar_t **__restrict, int);
 
-long long wcstoll (const wchar_t *, wchar_t **, int);
-unsigned long long wcstoull (const wchar_t *, wchar_t **, int);
+long long wcstoll (const wchar_t *__restrict, wchar_t **__restrict, int);
+unsigned long long wcstoull (const wchar_t *__restrict, wchar_t **__restrict, int);
 
 
 
 int fwide (FILE *, int);
 
 
-int wprintf (const wchar_t *, ...);
-int fwprintf (FILE *, const wchar_t *, ...);
-int swprintf (wchar_t *, size_t, const wchar_t *, ...);
+int wprintf (const wchar_t *__restrict, ...);
+int fwprintf (FILE *__restrict, const wchar_t *__restrict, ...);
+int swprintf (wchar_t *__restrict, size_t, const wchar_t *__restrict, ...);
 
-int vwprintf (const wchar_t *, va_list);
-int vfwprintf (FILE *, const wchar_t *, va_list);
-int vswprintf (wchar_t *, size_t, const wchar_t *, va_list);
+int vwprintf (const wchar_t *__restrict, va_list);
+int vfwprintf (FILE *__restrict, const wchar_t *__restrict, va_list);
+int vswprintf (wchar_t *__restrict, size_t, const wchar_t *__restrict, va_list);
 
-int wscanf (const wchar_t *, ...);
-int fwscanf (FILE *, const wchar_t *, ...);
-int swscanf (const wchar_t *, const wchar_t *, ...);
+int wscanf (const wchar_t *__restrict, ...);
+int fwscanf (FILE *__restrict, const wchar_t *__restrict, ...);
+int swscanf (const wchar_t *__restrict, const wchar_t *__restrict, ...);
 
-int vwscanf (const wchar_t *, va_list);
-int vfwscanf (FILE *, const wchar_t *, va_list);
-int vswscanf (const wchar_t *, const wchar_t *, va_list);
+int vwscanf (const wchar_t *__restrict, va_list);
+int vfwscanf (FILE *__restrict, const wchar_t *__restrict, va_list);
+int vswscanf (const wchar_t *__restrict, const wchar_t *__restrict, va_list);
 
 wint_t fgetwc (FILE *);
 wint_t getwc (FILE *);
@@ -122,31 +128,31 @@ wint_t fputwc (wchar_t, FILE *);
 wint_t putwc (wchar_t, FILE *);
 wint_t putwchar (wchar_t);
 
-wchar_t *fgetws (wchar_t *, int, FILE *);
-int fputws (const wchar_t *, FILE *);
+wchar_t *fgetws (wchar_t *__restrict, int, FILE *__restrict);
+int fputws (const wchar_t *__restrict, FILE *__restrict);
 
 wint_t ungetwc (wint_t, FILE *);
 
 struct tm;
-size_t wcsftime (wchar_t *, size_t, const wchar_t *, const struct tm *);
+size_t wcsftime (wchar_t *__restrict, size_t, const wchar_t *__restrict, const struct tm *__restrict);
 
 #undef iswdigit
 
 #if defined(_POSIX_SOURCE) || defined(_POSIX_C_SOURCE) \
  || defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE)
 FILE *open_wmemstream(wchar_t **, size_t *);
-size_t mbsnrtowcs(wchar_t *, const char **, size_t, size_t, mbstate_t *);
-size_t wcsnrtombs(char *, const wchar_t **, size_t, size_t, mbstate_t *);
+size_t mbsnrtowcs(wchar_t *__restrict, const char **__restrict, size_t, size_t, mbstate_t *__restrict);
+size_t wcsnrtombs(char *__restrict, const wchar_t **__restrict, size_t, size_t, mbstate_t *__restrict);
 wchar_t *wcsdup(const wchar_t *);
 size_t wcsnlen (const wchar_t *, size_t);
-wchar_t *wcpcpy (wchar_t *, const wchar_t *);
-wchar_t *wcpncpy (wchar_t *, const wchar_t *, size_t);
+wchar_t *wcpcpy (wchar_t *__restrict, const wchar_t *__restrict);
+wchar_t *wcpncpy (wchar_t *__restrict, const wchar_t *__restrict, size_t);
 int wcscasecmp(const wchar_t *, const wchar_t *);
 int wcscasecmp_l(const wchar_t *, const wchar_t *, locale_t);
 int wcsncasecmp(const wchar_t *, const wchar_t *, size_t);
 int wcsncasecmp_l(const wchar_t *, const wchar_t *, size_t, locale_t);
 int wcscoll_l(const wchar_t *, const wchar_t *, locale_t);
-size_t wcsxfrm_l(wchar_t *, const wchar_t *, size_t n, locale_t);
+size_t wcsxfrm_l(wchar_t *__restrict, const wchar_t *__restrict, size_t n, locale_t);
 #endif
 
 #if defined(_XOPEN_SOURCE) || defined(_GNU_SOURCE)
diff --git a/include/wordexp.h b/include/wordexp.h
index 0691c8ea..e7eb3255 100644
--- a/include/wordexp.h
+++ b/include/wordexp.h
@@ -5,6 +5,12 @@
 extern "C" {
 #endif
 
+#if __STDC_VERSION__ >= 199901L
+#define __restrict restrict
+#elif !defined(__GNUC__)
+#define __restrict
+#endif
+
 #define __NEED_size_t
 
 #include <bits/alltypes.h>
@@ -30,7 +36,7 @@ typedef struct
 #define WRDE_CMDSUB  4
 #define WRDE_SYNTAX  5
 
-int wordexp (const char *, wordexp_t *, int);
+int wordexp (const char *__restrict, wordexp_t *__restrict, int);
 void wordfree (wordexp_t *);
 
 #ifdef __cplusplus