diff --git a/libc/bionic/fortify.cpp b/libc/bionic/fortify.cpp
index cf50664..117de48 100644
--- a/libc/bionic/fortify.cpp
+++ b/libc/bionic/fortify.cpp
@@ -71,6 +71,8 @@
 
 #include "private/bionic_fortify.h"
 
+struct __bionic_zero_size_is_okay_t __bionic_zero_size_is_okay;
+
 //
 // For more details see:
 //   http://gcc.gnu.org/onlinedocs/gcc/Object-Size-Checking.html
diff --git a/libc/bionic/getcwd.cpp b/libc/bionic/getcwd.cpp
index bcd6a57..c2a7e23 100644
--- a/libc/bionic/getcwd.cpp
+++ b/libc/bionic/getcwd.cpp
@@ -34,7 +34,7 @@
 
 extern "C" int __getcwd(char* buf, size_t size);
 
-char* getcwd(char* buf, size_t size) {
+char* getcwd(char* buf, size_t size) __overloadable {
   // You can't specify size 0 unless you're asking us to allocate for you.
   if (buf != NULL && size == 0) {
     errno = EINVAL;
diff --git a/libc/bionic/poll.cpp b/libc/bionic/poll.cpp
index 23ef90a..eded56a 100644
--- a/libc/bionic/poll.cpp
+++ b/libc/bionic/poll.cpp
@@ -37,7 +37,7 @@
 extern "C" int __ppoll(pollfd*, unsigned int, timespec*, const kernel_sigset_t*, size_t);
 extern "C" int __pselect6(int, fd_set*, fd_set*, fd_set*, timespec*, void*);
 
-int poll(pollfd* fds, nfds_t fd_count, int ms) {
+int poll(pollfd* fds, nfds_t fd_count, int ms) __overloadable {
   timespec ts;
   timespec* ts_ptr = NULL;
   if (ms >= 0) {
@@ -47,7 +47,7 @@
   return __ppoll(fds, fd_count, ts_ptr, NULL, 0);
 }
 
-int ppoll(pollfd* fds, nfds_t fd_count, const timespec* ts, const sigset_t* ss) {
+int ppoll(pollfd* fds, nfds_t fd_count, const timespec* ts, const sigset_t* ss) __overloadable {
   timespec mutable_ts;
   timespec* mutable_ts_ptr = NULL;
   if (ts != NULL) {