thread, lock, cond, tls: Remove support for Pth threads.

* m4/threadlib.m4 (gl_THREADLIB_EARLY_BODY): Don't document
--enable-threads=pth any more.
(gl_THREADLIB_BODY): Don't set USE_PTH_THREADS any more.
* m4/pthread_sigmask.m4 (gl_FUNC_PTHREAD_SIGMASK): Update comment.
* m4/threads.m4 (gl_THREADS_H): Remove test for conflict between Pth
threads and ISO C11 threads.
* lib/glthread/thread.h: Remove code for USE_PTH_THREADS.
* lib/glthread/lock.h: Likewise.
* lib/glthread/lock.c: Likewise.
* lib/glthread/cond.h: Likewise.
* lib/glthread/cond.c: Likewise.
* lib/glthread/tls.h: Likewise.
* lib/glthread/tls.c: Likewise.
* lib/glthread/yield.h: Likewise.
* lib/regex_internal.h: Likewise.
* tests/test-thread_create.c: Likewise.
* tests/test-lock.c: Likewise.
* tests/test-cond.c: Likewise.
* tests/test-tls.c: Likewise.
* tests/test-rwlock1.c: Don't include glthread/yield.h.
(main): Sleep without calling gl_thread_yield.

8 files changed, 9 insertions, 560 deletions

diff --git a/lib/glthread/cond.c b/lib/glthread/cond.c
index 72aeca4a32..f6a06cc9fa 100644
--- a/lib/glthread/cond.c
+++ b/lib/glthread/cond.c
@@ -24,34 +24,6 @@
 
 /* ========================================================================= */
 
-#if USE_PTH_THREADS
-
-/* -------------------------- gl_cond_t datatype -------------------------- */
-
-int
-glthread_cond_timedwait_multithreaded (gl_cond_t *cond,
-                                       gl_lock_t *lock,
-                                       struct timespec *abstime)
-{
-  int ret, status;
-  pth_event_t ev;
-
-  ev = pth_event (PTH_EVENT_TIME, pth_time (abstime->tv_sec, abstime->tv_nsec / 1000));
-  ret = pth_cond_await (cond, lock, ev);
-
-  status = pth_event_status (ev);
-  pth_event_free (ev, PTH_FREE_THIS);
-
-  if (status == PTH_STATUS_OCCURRED)
-    return ETIMEDOUT;
-
-  return ret;
-}
-
-#endif
-
-/* ========================================================================= */
-
 #if USE_WINDOWS_THREADS
 
 #endif
diff --git a/lib/glthread/cond.h b/lib/glthread/cond.h
index b03ffe300c..4c6f4d94c0 100644
--- a/lib/glthread/cond.h
+++ b/lib/glthread/cond.h
@@ -56,7 +56,7 @@
 #include "glthread/lock.h"
 
 #if !defined c11_threads_in_use
-# if HAVE_THREADS_H && (USE_POSIX_THREADS_WEAK || USE_PTH_THREADS_WEAK)
+# if HAVE_THREADS_H && USE_POSIX_THREADS_WEAK
 #  include <threads.h>
 #  pragma weak thrd_exit
 #  define c11_threads_in_use() (thrd_exit != NULL)
@@ -168,65 +168,6 @@ typedef pthread_cond_t gl_cond_t;
 
 /* ========================================================================= */
 
-#if USE_PTH_THREADS
-
-/* Use the GNU Pth threads library.  */
-
-# include <pth.h>
-
-# ifdef __cplusplus
-extern "C" {
-# endif
-
-# if USE_PTH_THREADS_WEAK
-
-/* Use weak references to the GNU Pth threads library.  */
-
-#  pragma weak pth_cond_init
-#  pragma weak pth_cond_await
-#  pragma weak pth_cond_notify
-#  pragma weak pth_event
-#  pragma weak pth_timeout
-
-#  pragma weak pth_cancel
-#  define pth_in_use() (pth_cancel != NULL || c11_threads_in_use ())
-
-# else
-
-#  define pth_in_use() 1
-
-# endif
-
-/* -------------------------- gl_cond_t datatype -------------------------- */
-
-typedef pth_cond_t gl_cond_t;
-# define gl_cond_define(STORAGECLASS, NAME) \
-    STORAGECLASS gl_cond_t NAME;
-# define gl_cond_define_initialized(STORAGECLASS, NAME) \
-    STORAGECLASS gl_cond_t NAME = gl_cond_initializer;
-# define gl_cond_initializer \
-    PTH_COND_INIT
-# define glthread_cond_init(COND) \
-    (pth_in_use () && !pth_cond_init (COND) ? errno : 0)
-# define glthread_cond_wait(COND, LOCK) \
-    (pth_in_use () && !pth_cond_await (COND, LOCK, NULL) ? errno : 0)
-# define glthread_cond_timedwait(COND, LOCK, ABSTIME) \
-    (pth_in_use () ? glthread_cond_timedwait_multithreaded (COND, LOCK, ABSTIME) : 0)
-# define glthread_cond_signal(COND) \
-    (pth_in_use () && !pth_cond_notify (COND, FALSE) ? errno : 0)
-# define glthread_cond_broadcast(COND) \
-    (pth_in_use () && !pth_cond_notify (COND, TRUE) ? errno : 0)
-# define glthread_cond_destroy(COND) 0
-extern int glthread_cond_timedwait_multithreaded (gl_cond_t *cond, gl_lock_t *lock, struct timespec *abstime);
-
-# ifdef __cplusplus
-}
-# endif
-
-#endif
-
-/* ========================================================================= */
-
 #if USE_WINDOWS_THREADS
 
 # define WIN32_LEAN_AND_MEAN  /* avoid including junk */
@@ -273,7 +214,7 @@ typedef glwthread_cond_t gl_cond_t;
 
 /* ========================================================================= */
 
-#if !(USE_POSIX_THREADS || USE_PTH_THREADS || USE_WINDOWS_THREADS)
+#if !(USE_POSIX_THREADS || USE_WINDOWS_THREADS)
 
 /* Provide dummy implementation if threads are not supported.  */
 
diff --git a/lib/glthread/lock.c b/lib/glthread/lock.c
index e7fa3f8961..89f1f50ab1 100644
--- a/lib/glthread/lock.c
+++ b/lib/glthread/lock.c
@@ -499,186 +499,6 @@ glthread_once_singlethreaded (pthread_once_t *once_control)
 
 /* ========================================================================= */
 
-#if USE_PTH_THREADS
-
-/* Use the GNU Pth threads library.  */
-
-/* -------------------------- gl_lock_t datatype -------------------------- */
-
-/* ------------------------- gl_rwlock_t datatype ------------------------- */
-
-# if !HAVE_PTH_RWLOCK_ACQUIRE_PREFER_WRITER
-
-int
-glthread_rwlock_init_multithreaded (gl_rwlock_t *lock)
-{
-  if (!pth_mutex_init (&lock->lock))
-    return errno;
-  if (!pth_cond_init (&lock->waiting_readers))
-    return errno;
-  if (!pth_cond_init (&lock->waiting_writers))
-    return errno;
-  lock->waiting_writers_count = 0;
-  lock->runcount = 0;
-  lock->initialized = 1;
-  return 0;
-}
-
-int
-glthread_rwlock_rdlock_multithreaded (gl_rwlock_t *lock)
-{
-  if (!lock->initialized)
-    glthread_rwlock_init_multithreaded (lock);
-  if (!pth_mutex_acquire (&lock->lock, 0, NULL))
-    return errno;
-  /* Test whether only readers are currently running, and whether the runcount
-     field will not overflow, and whether no writer is waiting.  The latter
-     condition is because POSIX recommends that "write locks shall take
-     precedence over read locks", to avoid "writer starvation".  */
-  while (!(lock->runcount + 1 > 0 && lock->waiting_writers_count == 0))
-    {
-      /* This thread has to wait for a while.  Enqueue it among the
-         waiting_readers.  */
-      if (!pth_cond_await (&lock->waiting_readers, &lock->lock, NULL))
-        {
-          int err = errno;
-          pth_mutex_release (&lock->lock);
-          return err;
-        }
-    }
-  lock->runcount++;
-  return (!pth_mutex_release (&lock->lock) ? errno : 0);
-}
-
-int
-glthread_rwlock_wrlock_multithreaded (gl_rwlock_t *lock)
-{
-  if (!lock->initialized)
-    glthread_rwlock_init_multithreaded (lock);
-  if (!pth_mutex_acquire (&lock->lock, 0, NULL))
-    return errno;
-  /* Test whether no readers or writers are currently running.  */
-  while (!(lock->runcount == 0))
-    {
-      /* This thread has to wait for a while.  Enqueue it among the
-         waiting_writers.  */
-      lock->waiting_writers_count++;
-      if (!pth_cond_await (&lock->waiting_writers, &lock->lock, NULL))
-        {
-          int err = errno;
-          lock->waiting_writers_count--;
-          pth_mutex_release (&lock->lock);
-          return err;
-        }
-      lock->waiting_writers_count--;
-    }
-  lock->runcount--; /* runcount becomes -1 */
-  return (!pth_mutex_release (&lock->lock) ? errno : 0);
-}
-
-int
-glthread_rwlock_unlock_multithreaded (gl_rwlock_t *lock)
-{
-  int err;
-
-  if (!lock->initialized)
-    return EINVAL;
-  if (!pth_mutex_acquire (&lock->lock, 0, NULL))
-    return errno;
-  if (lock->runcount < 0)
-    {
-      /* Drop a writer lock.  */
-      if (!(lock->runcount == -1))
-        {
-          pth_mutex_release (&lock->lock);
-          return EINVAL;
-        }
-      lock->runcount = 0;
-    }
-  else
-    {
-      /* Drop a reader lock.  */
-      if (!(lock->runcount > 0))
-        {
-          pth_mutex_release (&lock->lock);
-          return EINVAL;
-        }
-      lock->runcount--;
-    }
-  if (lock->runcount == 0)
-    {
-      /* POSIX recommends that "write locks shall take precedence over read
-         locks", to avoid "writer starvation".  */
-      if (lock->waiting_writers_count > 0)
-        {
-          /* Wake up one of the waiting writers.  */
-          if (!pth_cond_notify (&lock->waiting_writers, FALSE))
-            {
-              int err = errno;
-              pth_mutex_release (&lock->lock);
-              return err;
-            }
-        }
-      else
-        {
-          /* Wake up all waiting readers.  */
-          if (!pth_cond_notify (&lock->waiting_readers, TRUE))
-            {
-              int err = errno;
-              pth_mutex_release (&lock->lock);
-              return err;
-            }
-        }
-    }
-  return (!pth_mutex_release (&lock->lock) ? errno : 0);
-}
-
-int
-glthread_rwlock_destroy_multithreaded (gl_rwlock_t *lock)
-{
-  lock->initialized = 0;
-  return 0;
-}
-
-# endif
-
-/* --------------------- gl_recursive_lock_t datatype --------------------- */
-
-/* -------------------------- gl_once_t datatype -------------------------- */
-
-static void
-glthread_once_call (void *arg)
-{
-  void (**gl_once_temp_addr) (void) = (void (**) (void)) arg;
-  void (*initfunction) (void) = *gl_once_temp_addr;
-  initfunction ();
-}
-
-int
-glthread_once_multithreaded (pth_once_t *once_control, void (*initfunction) (void))
-{
-  void (*temp) (void) = initfunction;
-  return (!pth_once (once_control, glthread_once_call, &temp) ? errno : 0);
-}
-
-int
-glthread_once_singlethreaded (pth_once_t *once_control)
-{
-  /* We know that pth_once_t is an integer type.  */
-  if (*once_control == PTH_ONCE_INIT)
-    {
-      /* First time use of once_control.  Invert the marker.  */
-      *once_control = ~ PTH_ONCE_INIT;
-      return 1;
-    }
-  else
-    return 0;
-}
-
-#endif
-
-/* ========================================================================= */
-
 #if USE_WINDOWS_THREADS
 
 /* ------------------------- gl_rwlock_t datatype ------------------------- */
diff --git a/lib/glthread/lock.h b/lib/glthread/lock.h
index 2db8b7ecab..bc3a4def38 100644
--- a/lib/glthread/lock.h
+++ b/lib/glthread/lock.h
@@ -81,7 +81,7 @@
 #include <stdlib.h>
 
 #if !defined c11_threads_in_use
-# if HAVE_THREADS_H && (USE_POSIX_THREADS_WEAK || USE_PTH_THREADS_WEAK)
+# if HAVE_THREADS_H && USE_POSIX_THREADS_WEAK
 #  include <threads.h>
 #  pragma weak thrd_exit
 #  define c11_threads_in_use() (thrd_exit != NULL)
@@ -405,156 +405,6 @@ extern int glthread_once_singlethreaded (pthread_once_t *once_control);
 
 /* ========================================================================= */
 
-#if USE_PTH_THREADS
-
-/* Use the GNU Pth threads library.  */
-
-# include <pth.h>
-
-# ifdef __cplusplus
-extern "C" {
-# endif
-
-# if USE_PTH_THREADS_WEAK
-
-/* Use weak references to the GNU Pth threads library.  */
-
-#  pragma weak pth_mutex_init
-#  pragma weak pth_mutex_acquire
-#  pragma weak pth_mutex_release
-#  pragma weak pth_rwlock_init
-#  pragma weak pth_rwlock_acquire
-#  pragma weak pth_rwlock_release
-#  pragma weak pth_once
-#  pragma weak pth_cond_init
-#  pragma weak pth_cond_await
-#  pragma weak pth_cond_notify
-
-#  pragma weak pth_cancel
-#  define pth_in_use() (pth_cancel != NULL || c11_threads_in_use ())
-
-# else
-
-#  define pth_in_use() 1
-
-# endif
-
-/* -------------------------- gl_lock_t datatype -------------------------- */
-
-typedef pth_mutex_t gl_lock_t;
-# define gl_lock_define(STORAGECLASS, NAME) \
-    STORAGECLASS pth_mutex_t NAME;
-# define gl_lock_define_initialized(STORAGECLASS, NAME) \
-    STORAGECLASS pth_mutex_t NAME = gl_lock_initializer;
-# define gl_lock_initializer \
-    PTH_MUTEX_INIT
-# define glthread_lock_init(LOCK) \
-    (pth_in_use () && !pth_mutex_init (LOCK) ? errno : 0)
-# define glthread_lock_lock(LOCK) \
-    (pth_in_use () && !pth_mutex_acquire (LOCK, 0, NULL) ? errno : 0)
-# define glthread_lock_unlock(LOCK) \
-    (pth_in_use () && !pth_mutex_release (LOCK) ? errno : 0)
-# define glthread_lock_destroy(LOCK) \
-    ((void)(LOCK), 0)
-
-/* ------------------------- gl_rwlock_t datatype ------------------------- */
-
-/* Pth pth_rwlock_acquire always prefers readers.  No autoconf test so far.  */
-# if HAVE_PTH_RWLOCK_ACQUIRE_PREFER_WRITER
-
-typedef pth_rwlock_t gl_rwlock_t;
-#  define gl_rwlock_define(STORAGECLASS, NAME) \
-     STORAGECLASS pth_rwlock_t NAME;
-#  define gl_rwlock_define_initialized(STORAGECLASS, NAME) \
-     STORAGECLASS pth_rwlock_t NAME = gl_rwlock_initializer;
-#  define gl_rwlock_initializer \
-     PTH_RWLOCK_INIT
-#  define glthread_rwlock_init(LOCK) \
-     (pth_in_use () && !pth_rwlock_init (LOCK) ? errno : 0)
-#  define glthread_rwlock_rdlock(LOCK) \
-     (pth_in_use () && !pth_rwlock_acquire (LOCK, PTH_RWLOCK_RD, 0, NULL) ? errno : 0)
-#  define glthread_rwlock_wrlock(LOCK) \
-     (pth_in_use () && !pth_rwlock_acquire (LOCK, PTH_RWLOCK_RW, 0, NULL) ? errno : 0)
-#  define glthread_rwlock_unlock(LOCK) \
-     (pth_in_use () && !pth_rwlock_release (LOCK) ? errno : 0)
-#  define glthread_rwlock_destroy(LOCK) \
-     ((void)(LOCK), 0)
-
-# else
-
-typedef struct
-        {
-          int initialized;
-          pth_mutex_t lock; /* protects the remaining fields */
-          pth_cond_t waiting_readers; /* waiting readers */
-          pth_cond_t waiting_writers; /* waiting writers */
-          unsigned int waiting_writers_count; /* number of waiting writers */
-          int runcount; /* number of readers running, or -1 when a writer runs */
-        }
-        gl_rwlock_t;
-#  define gl_rwlock_define(STORAGECLASS, NAME) \
-     STORAGECLASS gl_rwlock_t NAME;
-#  define gl_rwlock_define_initialized(STORAGECLASS, NAME) \
-     STORAGECLASS gl_rwlock_t NAME = gl_rwlock_initializer;
-#  define gl_rwlock_initializer \
-     { 0 }
-#  define glthread_rwlock_init(LOCK) \
-     (pth_in_use () ? glthread_rwlock_init_multithreaded (LOCK) : 0)
-#  define glthread_rwlock_rdlock(LOCK) \
-     (pth_in_use () ? glthread_rwlock_rdlock_multithreaded (LOCK) : 0)
-#  define glthread_rwlock_wrlock(LOCK) \
-     (pth_in_use () ? glthread_rwlock_wrlock_multithreaded (LOCK) : 0)
-#  define glthread_rwlock_unlock(LOCK) \
-     (pth_in_use () ? glthread_rwlock_unlock_multithreaded (LOCK) : 0)
-#  define glthread_rwlock_destroy(LOCK) \
-     (pth_in_use () ? glthread_rwlock_destroy_multithreaded (LOCK) : 0)
-extern int glthread_rwlock_init_multithreaded (gl_rwlock_t *lock);
-extern int glthread_rwlock_rdlock_multithreaded (gl_rwlock_t *lock);
-extern int glthread_rwlock_wrlock_multithreaded (gl_rwlock_t *lock);
-extern int glthread_rwlock_unlock_multithreaded (gl_rwlock_t *lock);
-extern int glthread_rwlock_destroy_multithreaded (gl_rwlock_t *lock);
-
-# endif
-
-/* --------------------- gl_recursive_lock_t datatype --------------------- */
-
-/* In Pth, mutexes are recursive by default.  */
-typedef pth_mutex_t gl_recursive_lock_t;
-#  define gl_recursive_lock_define(STORAGECLASS, NAME) \
-     STORAGECLASS pth_mutex_t NAME;
-#  define gl_recursive_lock_define_initialized(STORAGECLASS, NAME) \
-     STORAGECLASS pth_mutex_t NAME = gl_recursive_lock_initializer;
-#  define gl_recursive_lock_initializer \
-     PTH_MUTEX_INIT
-#  define glthread_recursive_lock_init(LOCK) \
-     (pth_in_use () && !pth_mutex_init (LOCK) ? errno : 0)
-#  define glthread_recursive_lock_lock(LOCK) \
-     (pth_in_use () && !pth_mutex_acquire (LOCK, 0, NULL) ? errno : 0)
-#  define glthread_recursive_lock_unlock(LOCK) \
-     (pth_in_use () && !pth_mutex_release (LOCK) ? errno : 0)
-#  define glthread_recursive_lock_destroy(LOCK) \
-     ((void)(LOCK), 0)
-
-/* -------------------------- gl_once_t datatype -------------------------- */
-
-typedef pth_once_t gl_once_t;
-# define gl_once_define(STORAGECLASS, NAME) \
-    STORAGECLASS pth_once_t NAME = PTH_ONCE_INIT;
-# define glthread_once(ONCE_CONTROL, INITFUNCTION) \
-    (pth_in_use ()                                                             \
-     ? glthread_once_multithreaded (ONCE_CONTROL, INITFUNCTION)                \
-     : (glthread_once_singlethreaded (ONCE_CONTROL) ? (INITFUNCTION (), 0) : 0))
-extern int glthread_once_multithreaded (pth_once_t *once_control, void (*initfunction) (void));
-extern int glthread_once_singlethreaded (pth_once_t *once_control);
-
-# ifdef __cplusplus
-}
-# endif
-
-#endif
-
-/* ========================================================================= */
-
 #if USE_WINDOWS_THREADS
 
 # define WIN32_LEAN_AND_MEAN  /* avoid including junk */
@@ -677,7 +527,7 @@ typedef glwthread_once_t gl_once_t;
 
 /* ========================================================================= */
 
-#if !(USE_POSIX_THREADS || USE_PTH_THREADS || USE_WINDOWS_THREADS)
+#if !(USE_POSIX_THREADS || USE_WINDOWS_THREADS)
 
 /* Provide dummy implementation if threads are not supported.  */
 
diff --git a/lib/glthread/thread.h b/lib/glthread/thread.h
index eed2eb6e9c..eef9a46aff 100644
--- a/lib/glthread/thread.h
+++ b/lib/glthread/thread.h
@@ -74,7 +74,7 @@
 #include <stdlib.h>
 
 #if !defined c11_threads_in_use
-# if HAVE_THREADS_H && (USE_POSIX_THREADS_WEAK || USE_PTH_THREADS_WEAK)
+# if HAVE_THREADS_H && USE_POSIX_THREADS_WEAK
 #  include <threads.h>
 #  pragma weak thrd_exit
 #  define c11_threads_in_use() (thrd_exit != NULL)
@@ -222,60 +222,6 @@ extern const gl_thread_t gl_null_thread;
 
 /* ========================================================================= */
 
-#if USE_PTH_THREADS
-
-/* Use the GNU Pth threads library.  */
-
-# include <pth.h>
-
-# ifdef __cplusplus
-extern "C" {
-# endif
-
-# if USE_PTH_THREADS_WEAK
-
-/* Use weak references to the GNU Pth threads library.  */
-
-#  pragma weak pth_init
-#  pragma weak pth_spawn
-#  pragma weak pth_sigmask
-#  pragma weak pth_join
-#  pragma weak pth_self
-#  pragma weak pth_exit
-
-#  pragma weak pth_cancel
-#  define pth_in_use() (pth_cancel != NULL || c11_threads_in_use ())
-
-# else
-
-#  define pth_in_use() 1
-
-# endif
-/* -------------------------- gl_thread_t datatype -------------------------- */
-
-typedef pth_t gl_thread_t;
-# define glthread_create(THREADP, FUNC, ARG) \
-    (pth_in_use () ? (pth_init (), ((*(THREADP) = pth_spawn (NULL, FUNC, ARG)) ? 0 : errno)) : 0)
-# define glthread_sigmask(HOW, SET, OSET) \
-    (pth_in_use () ? (pth_init (), (pth_sigmask (HOW, SET, OSET) ? 0 : errno)) : 0)
-# define glthread_join(THREAD, RETVALP) \
-    (pth_in_use () ? (pth_init (), (pth_join (THREAD, RETVALP) ? 0 : errno)) : 0)
-# define gl_thread_self() \
-    (pth_in_use () ? (pth_init (), (void *) pth_self ()) : NULL)
-# define gl_thread_self_pointer() \
-    gl_thread_self ()
-# define gl_thread_exit(RETVAL) \
-    (pth_in_use () ? (pth_init (), pth_exit (RETVAL)) : 0)
-# define glthread_atfork(PREPARE_FUNC, PARENT_FUNC, CHILD_FUNC) 0
-
-# ifdef __cplusplus
-}
-# endif
-
-#endif
-
-/* ========================================================================= */
-
 #if USE_WINDOWS_THREADS
 
 # define WIN32_LEAN_AND_MEAN  /* avoid including junk */
@@ -312,7 +258,7 @@ typedef glwthread_thread_t gl_thread_t;
 
 /* ========================================================================= */
 
-#if !(USE_POSIX_THREADS || USE_PTH_THREADS || USE_WINDOWS_THREADS)
+#if !(USE_POSIX_THREADS || USE_WINDOWS_THREADS)
 
 /* Provide dummy implementation if threads are not supported.  */
 
diff --git a/lib/glthread/tls.c b/lib/glthread/tls.c
index cc6d4e1b4a..d182266c56 100644
--- a/lib/glthread/tls.c
+++ b/lib/glthread/tls.c
@@ -28,12 +28,6 @@
 
 /* ========================================================================= */
 
-#if USE_PTH_THREADS
-
-#endif
-
-/* ========================================================================= */
-
 #if USE_WINDOWS_THREADS
 
 #endif
diff --git a/lib/glthread/tls.h b/lib/glthread/tls.h
index a86dcd46ec..cfc96061c1 100644
--- a/lib/glthread/tls.h
+++ b/lib/glthread/tls.h
@@ -47,7 +47,7 @@
 #include <stdlib.h>
 
 #if !defined c11_threads_in_use
-# if HAVE_THREADS_H && (USE_POSIX_THREADS_WEAK || USE_PTH_THREADS_WEAK)
+# if HAVE_THREADS_H && USE_POSIX_THREADS_WEAK
 #  include <threads.h>
 #  pragma weak thrd_exit
 #  define c11_threads_in_use() (thrd_exit != NULL)
@@ -126,59 +126,6 @@ typedef union
 
 /* ========================================================================= */
 
-#if USE_PTH_THREADS
-
-/* Use the GNU Pth threads library.  */
-
-# include <pth.h>
-
-# if USE_PTH_THREADS_WEAK
-
-/* Use weak references to the GNU Pth threads library.  */
-
-#  pragma weak pth_key_create
-#  pragma weak pth_key_getdata
-#  pragma weak pth_key_setdata
-#  pragma weak pth_key_delete
-
-#  pragma weak pth_cancel
-#  define pth_in_use() (pth_cancel != NULL || c11_threads_in_use ())
-
-# else
-
-#  define pth_in_use() 1
-
-# endif
-
-/* ------------------------- gl_tls_key_t datatype ------------------------- */
-
-typedef union
-        {
-          void *singlethread_value;
-          pth_key_t key;
-        }
-        gl_tls_key_t;
-# define glthread_tls_key_init(KEY, DESTRUCTOR) \
-    (pth_in_use ()                                             \
-     ? (!pth_key_create (&(KEY)->key, DESTRUCTOR) ? errno : 0) \
-     : ((KEY)->singlethread_value = NULL, 0))
-# define gl_tls_get(NAME) \
-    (pth_in_use ()                  \
-     ? pth_key_getdata ((NAME).key) \
-     : (NAME).singlethread_value)
-# define glthread_tls_set(KEY, POINTER) \
-    (pth_in_use ()                                            \
-     ? (!pth_key_setdata ((KEY)->key, (POINTER)) ? errno : 0) \
-     : ((KEY)->singlethread_value = (POINTER), 0))
-# define glthread_tls_key_destroy(KEY) \
-    (pth_in_use ()                                \
-     ? (!pth_key_delete ((KEY)->key) ? errno : 0) \
-     : 0)
-
-#endif
-
-/* ========================================================================= */
-
 #if USE_WINDOWS_THREADS
 
 # define WIN32_LEAN_AND_MEAN  /* avoid including junk */
@@ -202,7 +149,7 @@ typedef glwthread_tls_key_t gl_tls_key_t;
 
 /* ========================================================================= */
 
-#if !(USE_POSIX_THREADS || USE_PTH_THREADS || USE_WINDOWS_THREADS)
+#if !(USE_POSIX_THREADS || USE_WINDOWS_THREADS)
 
 /* Provide dummy implementation if threads are not supported.  */
 
diff --git a/lib/glthread/yield.h b/lib/glthread/yield.h
index 3a2877b1a5..27bca55b79 100644
--- a/lib/glthread/yield.h
+++ b/lib/glthread/yield.h
@@ -46,27 +46,6 @@ extern "C" {
 
 /* ========================================================================= */
 
-#if USE_PTH_THREADS
-
-/* Use the GNU Pth threads library.  */
-
-# include <pth.h>
-
-# ifdef __cplusplus
-extern "C" {
-# endif
-
-# define gl_thread_yield() \
-    pth_yield (NULL)
-
-# ifdef __cplusplus
-}
-# endif
-
-#endif
-
-/* ========================================================================= */
-
 #if USE_WINDOWS_THREADS
 
 # define WIN32_LEAN_AND_MEAN  /* avoid including junk */
@@ -87,7 +66,7 @@ extern "C" {
 
 /* ========================================================================= */
 
-#if !(USE_POSIX_THREADS || USE_PTH_THREADS || USE_WINDOWS_THREADS)
+#if !(USE_POSIX_THREADS || USE_WINDOWS_THREADS)
 
 /* Provide dummy implementation if threads are not supported.  */