From 283712d6bcb4949b7dba5c1af10f15614cb48928 Mon Sep 17 00:00:00 2001
From: Ryan Mansfield <ryan_mansfield@apple.com>
Date: Tue, 30 Sep 2025 16:04:58 -0400
Subject: [PATCH] Fix swift driver hanging on SIGINT by adding timeout forced
 exit

When users interrupt swift driver with ctrl+c, the llbuild engine.build()
call can hang indefinitely even after child processes are terminated.
Add a two second timeout to force exit if graceful termination fails.

Resolves https://github.com/swiftlang/swift-driver/issues/1798
---
 Sources/swift-driver/main.swift | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/Sources/swift-driver/main.swift b/Sources/swift-driver/main.swift
index d34ee8115..baa6610d4 100644
--- a/Sources/swift-driver/main.swift
+++ b/Sources/swift-driver/main.swift
@@ -67,6 +67,11 @@ do {
     // to return a corresponding exit code when done.
     processSet.terminate()
     driverInterrupted = true
+
+    // If graceful termination doesn't work within a reasonable time, force exit
+    DispatchQueue.global().asyncAfter(deadline: .now() + 2.0) {
+      exit(1)
+    }
   }
   interruptSignalSource.resume()