Swift Compiler crash when building swift-testing with cmake

[Kyle-Ye]

Description

Following the Using CMake to build the project for macOS in CONTRIBUTING.md.

I got some compiler crash using Xcode 16.0.0's default Swift toolchain or the latest open source Swift 6.0.2 toolchain.

Expected behavior

Compile fine.

Actual behavior

Crash:

error: compile command failed due to signal 6 (use -v to see invocation)
Begin Error in Function: '$s7Testing13ConfigurationV15exitTestHandleryAA04ExitD9ArtifactsVAA0fD0VYaYbKcvpfiAfHYaYbKcfU_'
Found outside of lifetime use?!
Value:   %2 = load_borrow %1 : $*ExitTest                // users: %8, %4, %3
Consuming User:   end_borrow %2 : $ExitTest                       // id: %4
Non Consuming User:   debug_value %2 : $ExitTest, let, name "_0", argno 1 // id: %8
Block: bb0

End Error in Function: '$s7Testing13ConfigurationV15exitTestHandleryAA04ExitD9ArtifactsVAA0fD0VYaYbKcvpfiAfHYaYbKcfU_'
Found ownership error?!
triggering standard assertion failure routine
UNREACHABLE executed at /Users/ec2-user/jenkins/workspace/oss-swift-6.0.2-package-macos/swift/lib/SIL/Verifier/LinearLifetimeCheckerPrivate.h:211!
Please submit a bug report (https://swift.org/contributing/#reporting-bugs) and include the crash backtrace.

Full log file

log.txt

Steps to reproduce

gh repo clone swiftlang/swift-testing
cd swift-testing
# export CMAKE_Swift_COMPILER='/Library/Developer/Toolchains/swift-6.0.2-RELEASE.xctoolchain/usr/bin/swiftc'
cmake -G Ninja -B build
cmake --build build

swift-testing version/commit hash

a4ed760ce69261101fefffd1abf78ea663a4a44c

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

swift-driver version: 1.115 Apple Swift version 6.0 (swiftlang-6.0.0.9.10 clang-1600.0.26.2)
Target: arm64-apple-macosx15.0
Darwin Kyle-MiniMax.local 24.1.0 Darwin Kernel Version 24.1.0: Thu Oct 10 21:03:11 PDT 2024; root:xnu-11215.41.3~2/RELEASE_ARM64_T6020 arm64

CMake version

cmake version 3.30.5

CMake suite maintained and supported by Kitware (kitware.com/cmake).

[Kyle-Ye]

Looks like the doc is added via swiftlang/swift-testing#835. Would you help give an eye on this? cc @stmontgomery

[Kyle-Ye]

Checking the log, it says Compiling with effective version 5.10.

But we have set the swift version to 6 in the root CMakeLists.txt file via set(CMAKE_Swift_LANGUAGE_VERSION 6)

[grynspan]

Transferred because of the compiler crash. Thanks for filing!

[stmontgomery]

I was about to transfer as well and agree. Note that the -swift-version compiler flag is 6 as expected, that "effective version" log message is a red herring.

[Kyle-Ye]

Is there any suggested easy way to workaround it temporary? (Have tried to reset the HEAD into the 6 days ago, still not work)

I'm playing with some swift-testing patch and I'd like to verify it with the cmake build.

[stmontgomery]

You could try a release/6.1 or main branch snapshot toolchain instead. Trying one of those and posting the result here might help narrow down the issue, too.

[Kyle-Ye]

You could try a release/6.1 or main branch snapshot toolchain instead. Trying one of those and posting the result here might help narrow down the issue, too.

The issue is originally happening on the latest main branch. Tried with release/6.1 branch, it is the same crash issue.

[Kyle-Ye]

It seems the crash has been fixed with the latest commit for swift-testing. e2ec0411e5f7407fc2d325c9feea8f0ac10a60e2