From e9b10b21f11a84a8fbf74ce663935c7caea563fa Mon Sep 17 00:00:00 2001
From: Andres Amaya Garcia <Andres.AmayaGarcia@arm.com>
Date: Wed, 5 Sep 2018 11:25:30 +0100
Subject: [PATCH] Define _POSIX_C_SOURCE in threading.c before POSIX detection

---
 library/threading.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/library/threading.c b/library/threading.c
index 3d7f61b2e..c22a1dadc 100644
--- a/library/threading.c
+++ b/library/threading.c
@@ -19,6 +19,12 @@
  *  This file is part of mbed TLS (https://tls.mbed.org)
  */
 
+/*
+ * Ensure gmtime_r is available even with -std=c99; must be included before
+ * config.h, which pulls in glibc's features.h. Harmless on other platforms.
+ */
+#define _POSIX_C_SOURCE 200112L
+
 #if !defined(MBEDTLS_CONFIG_FILE)
 #include "mbedtls/config.h"
 #else