diff --git a/Package.swift b/Package.swift
index 58c8b86a2..58ac2cad7 100644
--- a/Package.swift
+++ b/Package.swift
@@ -221,9 +221,9 @@ var sharedSwiftSettings: [SwiftSetting] = [
 
     .define("OPENSWIFTUI_RELEASE_\(releaseVersion)"),
     .unsafeFlags(["-Xfrontend", "-experimental-spi-only-imports"]),
-    // Swift 6.3.3 crashes while indexing AppKit with the private framework shims.
+    // Swift 6.3.3 can crash while indexing UIKit or AppKit with the private framework shims.
     // Keep source indexing enabled while skipping imported system modules.
-    .unsafeFlags(["-index-ignore-system-modules"], .when(platforms: [.macOS])),
+    .unsafeFlags(["-index-ignore-system-modules"], .when(platforms: [.macOS, .iOS])),
 ]
 
 if releaseVersion >= 2021 {