From 43d2159be102d7561833a44ca144a26d8a56366a Mon Sep 17 00:00:00 2001
From: Yuta Saito <kateinoigakukun@gmail.com>
Date: Sat, 4 Sep 2021 07:45:29 +0000
Subject: [PATCH] StdlibUnittest: import _Concurrency explicitly

StdlibUnittest is built with `-disable-implicit-concurrency-module-import`
and it uses concurrency feature. Therefore, without explicit import,
StdlibUnittest.swiftmodule doesn't have `IMPORTED_MODULE` entry of
`_Concurrency`. And it results link-failure when static linking because
swift_Concurrency is not linked.
---
 stdlib/private/StdlibUnittest/StdlibUnittest.swift | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/stdlib/private/StdlibUnittest/StdlibUnittest.swift b/stdlib/private/StdlibUnittest/StdlibUnittest.swift
index 57d19a7cfee62..d06263c3f2044 100644
--- a/stdlib/private/StdlibUnittest/StdlibUnittest.swift
+++ b/stdlib/private/StdlibUnittest/StdlibUnittest.swift
@@ -31,6 +31,10 @@ import WinSDK
 import ObjectiveC
 #endif
 
+#if SWIFT_ENABLE_EXPERIMENTAL_CONCURRENCY
+import _Concurrency
+#endif
+
 extension String {
   /// Returns the lines in `self`.
   public var _lines : [String] {