fix static linking dependency bloat with cancellation

previously, pthread_cleanup_push/pop were pulling in all of
pthread_create due to dependency on the __pthread_unwind_next
function. this was not needed, as cancellation cleanup handlers can
never be called unless pthread_exit or pthread_cancel is reachable.

1 files changed, 12 insertions, 0 deletions

diff --git a/src/thread/cancellation.c b/src/thread/cancellation.c
index 4976fedc..6dfee539 100644
--- a/src/thread/cancellation.c
+++ b/src/thread/cancellation.c
@@ -3,10 +3,22 @@
 #ifdef __pthread_register_cancel
 #undef __pthread_register_cancel
 #undef __pthread_unregister_cancel
+#undef __pthread_unwind_next
 #define __pthread_register_cancel __pthread_register_cancel_3
 #define __pthread_unregister_cancel __pthread_unregister_cancel_3
+#define __pthread_unwind_next __pthread_unwind_next_3
 #endif
 
+static void dummy(struct __ptcb *cb)
+{
+}
+weak_alias(dummy, __pthread_do_unwind);
+
+void __pthread_unwind_next(struct __ptcb *cb)
+{
+	__pthread_do_unwind(cb);
+}
+
 void __pthread_register_cancel(struct __ptcb *cb)
 {
 	struct pthread *self = pthread_self();