diff --git a/libc/include/poll.h b/libc/include/poll.h
index 13b7385..e3a9039 100644
--- a/libc/include/poll.h
+++ b/libc/include/poll.h
@@ -49,7 +49,7 @@
  * Returns the number of ready file descriptors on success, 0 for timeout,
  * and returns -1 and sets `errno` on failure.
  */
-int poll(struct pollfd* _Nonnull __fds, nfds_t __count, int __timeout_ms);
+int poll(struct pollfd* _Nullable __fds, nfds_t __count, int __timeout_ms);
 
 /**
  * [ppoll(3)](http://man7.org/linux/man-pages/man3/ppoll.3.html) waits on a set of file descriptors
@@ -61,12 +61,12 @@
  *
  * Available since API level 28.
  */
-int ppoll(struct pollfd* _Nonnull __fds, nfds_t __count, const struct timespec* _Nullable __timeout, const sigset_t* _Nullable __mask) __INTRODUCED_IN(21);
+int ppoll(struct pollfd* _Nullable __fds, nfds_t __count, const struct timespec* _Nullable __timeout, const sigset_t* _Nullable __mask) __INTRODUCED_IN(21);
 
 /**
  * Like ppoll() but allows setting a signal mask with RT signals even from a 32-bit process.
  */
-int ppoll64(struct pollfd* _Nonnull __fds, nfds_t __count, const struct timespec* _Nullable __timeout, const sigset64_t* _Nullable __mask) __INTRODUCED_IN(28);
+int ppoll64(struct pollfd* _Nullable  __fds, nfds_t __count, const struct timespec* _Nullable __timeout, const sigset64_t* _Nullable __mask) __INTRODUCED_IN(28);
 
 #if defined(__BIONIC_INCLUDE_FORTIFY_HEADERS)
 #define _POLL_H_