diff --git a/openssl-sys-extras/src/openssl_shim.c b/openssl-sys-extras/src/openssl_shim.c
index a4b40280..11df1ca6 100644
--- a/openssl-sys-extras/src/openssl_shim.c
+++ b/openssl-sys-extras/src/openssl_shim.c
@@ -3,32 +3,6 @@
 #include <openssl/dh.h>
 #include <openssl/bn.h>
 
-#if defined(__APPLE__) || defined(__linux)
-
-#include <pthread.h>
-#include <openssl/crypto.h>
-
-unsigned long thread_id()
-{
-    return (unsigned long) pthread_self();
-}
-
-void rust_openssl_set_id_callback() {
-  CRYPTO_set_id_callback(thread_id);
-}
-
-#else
-// Openssl already handles Windows directly, so we don't
-// need to explicitly set it
-
-void rust_openssl_set_id_callback() {
-  // We don't know how to set the callback for arbitrary OSes
-  // Let openssl use its defaults and hope they work.
-}
-
-#endif
-
-
 #if OPENSSL_VERSION_NUMBER < 0x10000000L
 // Copied from openssl crypto/hmac/hmac.c
 int HMAC_CTX_copy(HMAC_CTX *dctx, HMAC_CTX *sctx)