diff --git a/libc/include/pthread.h b/libc/include/pthread.h
index 97f023d..8d95a3b 100644
--- a/libc/include/pthread.h
+++ b/libc/include/pthread.h
@@ -230,7 +230,7 @@
 int pthread_setname_np(pthread_t __pthread, const char* __name);
 
 int pthread_setschedparam(pthread_t __pthread, int __policy, const struct sched_param* __param);
-int pthread_setschedprio(pthread_t __pthread, int __priority) __INTRODUCED_IN_FUTURE;
+int pthread_setschedprio(pthread_t __pthread, int __priority) __INTRODUCED_IN(28);
 
 int pthread_setspecific(pthread_key_t __key, const void* __value);