From 7dadf858f18d9e3e24ff48a5432b503c2d99952b Mon Sep 17 00:00:00 2001
From: Paul Beusterien <paulbeusterien@google.com>
Date: Thu, 10 Jun 2021 10:33:55 -0700
Subject: [PATCH] Fix future version of the Apple toolchain failure (#25611)

More detail at https://github.com/firebase/firebase-ios-sdk/pull/7563
---
 src/core/tsi/alts/crypt/gsec.h | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/core/tsi/alts/crypt/gsec.h b/src/core/tsi/alts/crypt/gsec.h
index c330ca69eb5..f7d1cdaec2c 100644
--- a/src/core/tsi/alts/crypt/gsec.h
+++ b/src/core/tsi/alts/crypt/gsec.h
@@ -29,12 +29,14 @@
 
 #include <grpc/grpc.h>
 
+#ifndef _STRUCT_IOVEC
 #ifndef GRPC_EVENT_ENGINE_POSIX
 struct iovec {
   void* iov_base;
   size_t iov_len;
 };
 #endif  // GRPC_EVENT_ENGINE_POSIX
+#endif  // _STRUCT_IOVEC
 
 /**
  * A gsec interface for AEAD encryption schemes. The API is thread-compatible.