From c2e57a67eccb7ef95d998723baea9bb6f37f49e4 Mon Sep 17 00:00:00 2001
From: Walter Bright <walter@walterbright.com>
Date: Mon, 9 May 2016 00:52:25 -0700
Subject: [PATCH] fix Issue 13727 - std.stdio.File not thread-safe

---
 test/runnable/extra-files/extra13727.txt |  1 +
 test/runnable/test13727.d                | 23 +++++++++++++++++++++++
 2 files changed, 24 insertions(+)
 create mode 100644 test/runnable/extra-files/extra13727.txt
 create mode 100644 test/runnable/test13727.d

diff --git a/test/runnable/extra-files/extra13727.txt b/test/runnable/extra-files/extra13727.txt
new file mode 100644
index 000000000000..6530e9aceb3a
--- /dev/null
+++ b/test/runnable/extra-files/extra13727.txt
@@ -0,0 +1 @@
+It doesn't matter what this file contains, any old junk will do.
diff --git a/test/runnable/test13727.d b/test/runnable/test13727.d
new file mode 100644
index 000000000000..d39e2086cd29
--- /dev/null
+++ b/test/runnable/test13727.d
@@ -0,0 +1,23 @@
+// https://issues.dlang.org/show_bug.cgi?id=13727
+
+import std.array;
+import std.parallelism;
+import std.stdio;
+
+void main()
+{
+    foreach (fn;
+        ["runnable/extra-files/extra13727.txt"]
+        .replicate(1000)
+        .parallel
+    )
+    {
+        // synchronized
+	version (Windows)
+	    string mode = "rb";
+	else
+	    string mode = "r";
+        { File f = File(fn, mode); }
+    }
+}
+