swift package show-dependencies taking inordinate amount of time with Xcode 16 toolchain

[brianmichel]

Is it reproducible with SwiftPM command-line tools: swift build, swift test, swift package etc?

• Confirmed reproduction steps with SwiftPM CLI. The description text must include reproduction steps with either of command-line SwiftPM commands, swift build, swift test, swift package etc.

Description

We use swift package show-dependencies --disable-automatic-resolution --multiroot-data-file ./App.xcworkspace --scratch-path path/to/checked/out/packages to parse warnings and add them to github prs. Starting with Xcode 16 this command now takes roughly 10 minutes to complete when it used to just be a minute or two. This seems like a pretty major regression.

Expected behavior

I would expect this to complete in a reasonable amount of time (single digit minutes) like it used to prior to Xcode 16.

Actual behavior

This takes 10 or so minutes to complete in a larger project when it used to take single digit minutes. There is also no log output for a very long time after working copies have been checked out which makes this even harder to debug locally.

Steps to reproduce

1. run the command as mentioned

Swift Package Manager version/commit hash

No response

Swift & OS version (output of swift --version ; uname -a)

swift-driver version: 1.115 Apple Swift version 6.0.2 (swiftlang-6.0.2.1.2 clang-1600.0.26.4)
Target: arm64-apple-macosx14.0
Darwin brianmichel-WN7VD2T019 23.6.0 Darwin Kernel Version 23.6.0: Thu Sep 12 23:35:29 PDT 2024; root:xnu-10063.141.1.701.1~1/RELEASE_ARM64_T6000 arm64

[brianmichel]

As a work around would swift package describe print similar package warnings?