3 files changed, 15 insertions, 5 deletions
diff --git a/lib/glthread/lock.c b/lib/glthread/lock.c
index df05dbc0..9e148910 100644
--- a/lib/glthread/lock.c
+++ b/lib/glthread/lock.c
@@ -1,5 +1,5 @@
 /* Locking in multithreaded situations.
-   Copyright (C) 2005-2017 Free Software Foundation, Inc.
+   Copyright (C) 2005-2018 Free Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or
    modify it under the terms of either:
diff --git a/lib/glthread/lock.h b/lib/glthread/lock.h
index 06285558..ffb2b0e5 100644
--- a/lib/glthread/lock.h
+++ b/lib/glthread/lock.h
@@ -1,5 +1,5 @@
 /* Locking in multithreaded situations.
-   Copyright (C) 2005-2017 Free Software Foundation, Inc.
+   Copyright (C) 2005-2018 Free Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or
    modify it under the terms of either:
@@ -158,8 +158,18 @@ extern int glthread_in_use (void);
 #  endif
 
 #  if !PTHREAD_IN_USE_DETECTION_HARD
-#   pragma weak pthread_cancel
-#   define pthread_in_use() (pthread_cancel != NULL)
+    /* On most platforms, pthread_cancel or pthread_kill can be used to
+       determine whether libpthread is in use.
+       On newer versions of FreeBSD, however, this is no longer possible,
+       because pthread_cancel and pthread_kill got added to libc.  Therefore
+       use pthread_create to test whether libpthread is in use.  */
+#   if defined __FreeBSD__ || defined __DragonFly__ /* FreeBSD */
+#    pragma weak pthread_create
+#    define pthread_in_use() (pthread_create != NULL)
+#   else /* glibc, NetBSD, OpenBSD, IRIX, OSF/1, Solaris */
+#    pragma weak pthread_cancel
+#    define pthread_in_use() (pthread_cancel != NULL)
+#   endif
 #  endif
 
 # else
diff --git a/lib/glthread/threadlib.c b/lib/glthread/threadlib.c
index 82b8861b..3534b61e 100644
--- a/lib/glthread/threadlib.c
+++ b/lib/glthread/threadlib.c
@@ -1,5 +1,5 @@
 /* Multithreading primitives.
-   Copyright (C) 2005-2017 Free Software Foundation, Inc.
+   Copyright (C) 2005-2018 Free Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or
    modify it under the terms of either: