From 2ec8efea9155498e7f0fa2018542696d110fcd84 Mon Sep 17 00:00:00 2001
From: Allan Shortlidge <shortlidge@apple.com>
Date: Mon, 9 Sep 2024 12:25:22 -0700
Subject: [PATCH] Sema: Allow some @_implementationOnly imports in stdlib
 modules.

The `_Concurrency` module imports a C module that is not available in the
toolchain or SDK, which means that `@_implementationOnly` must be used to hide
the dependency on this module from clients.
---
 lib/Sema/ImportResolution.cpp | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/lib/Sema/ImportResolution.cpp b/lib/Sema/ImportResolution.cpp
index 355a31b37a3..80c7f453bea 100644
--- a/lib/Sema/ImportResolution.cpp
+++ b/lib/Sema/ImportResolution.cpp
@@ -797,6 +797,9 @@ void UnboundImport::validateInterfaceWithPackageName(ModuleDecl *topLevelModule,
 /// be hidden from clients.
 static bool shouldSuppressNonResilientImplementationOnlyImportDiagnostic(
     StringRef targetName, StringRef importerName) {
+  if (targetName == "SwiftConcurrencyInternalShims")
+    return importerName == "_Concurrency";
+
   if (targetName == "CCryptoBoringSSL" || targetName == "CCryptoBoringSSLShims")
     return importerName == "Crypto" || importerName == "_CryptoExtras" ||
            importerName == "CryptoBoringWrapper";