diff --git a/compat/dispatch_semaphore/semaphore.h b/compat/dispatch_semaphore/semaphore.h
new file mode 100644
index 0000000000..008c637c01
--- /dev/null
+++ b/compat/dispatch_semaphore/semaphore.h
@@ -0,0 +1,42 @@
+/*
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#ifndef COMPAT_DISPATCH_SEMAPHORE_SEMAPHORE_H
+#define COMPAT_DISPATCH_SEMAPHORE_SEMAPHORE_H
+
+#include <dispatch/dispatch.h>
+#include <errno.h>
+
+#define sem_t dispatch_semaphore_t
+#define sem_post(psem)              dispatch_semaphore_signal(*psem)
+#define sem_wait(psem)              dispatch_semaphore_wait(*psem, DISPATCH_TIME_FOREVER)
+#define sem_timedwait(psem, val)    dispatch_semaphore_wait(*psem, dispatch_walltime(val, 0))
+#define sem_destroy(psem)           dispatch_release(*psem)
+
+static inline int compat_sem_init(dispatch_semaphore_t *psem,
+                                  int unused, int val)
+{
+    int ret = !!(*psem = dispatch_semaphore_create(val)) - 1;
+    if (ret < 0)
+        errno = ENOMEM;
+    return ret;
+}
+
+#define sem_init compat_sem_init
+
+#endif /* COMPAT_DISPATCH_SEMAPHORE_SEMAPHORE_H */
diff --git a/configure b/configure
index 21808eae52..bbf5709528 100755
--- a/configure
+++ b/configure
@@ -4615,7 +4615,8 @@ case $target_os in
         enabled x86_64 && objformat="macho64"
         enabled_any pic shared x86_64 ||
             { check_cflags -mdynamic-no-pic && add_asflags -mdynamic-no-pic; }
-        check_header dispatch/dispatch.h
+        check_header dispatch/dispatch.h &&
+            add_cppflags '-I\$(SRC_PATH)/compat/dispatch_semaphore'
         ;;
     msys*)
         die "Native MSYS builds are discouraged, please use the MINGW environment.";
@@ -5522,6 +5523,9 @@ if enabled pthreads; then
   check_func pthread_cancel
 fi
 
+enabled pthreads &&
+    check_builtin sem_timedwait semaphore.h "sem_t *s; sem_init(s,0,0); sem_timedwait(s,0); sem_destroy(s)"
+
 disabled  zlib || check_lib   zlib.h      zlibVersion -lz   || disable  zlib
 disabled bzlib || check_lib2 bzlib.h BZ2_bzlibVersion -lbz2 || disable bzlib
 disabled  lzma || check_lib2  lzma.h lzma_version_number -llzma || disable lzma