XCode 9.2 Server build bot is unable to compile large projects
This repository is intended to demonstrate the bug reported to Apple as incident 36711458.
It seems a build bot (tested with XCode 9.2 (9C40b)) is unable to compile a project if the number of files in a target exceeds some limit.
The branch does_work of this repository contains a target with 2099 files to be compiled. A build bot configured to integrate this branch is working:
If the 2100th file is added to the target, the build is unable to succeed: According to the build log, the build phase
Compile Sources is missing the step
CompileSwiftSources normal arm64 com.apple.xcode.tools.swift.compiler which leads to a linker failure in a subsequent step:
You can find the log files in this repository under Assets.
Using xcodebuild on the command line is not failing in both cases.
I do not think the issue depends on the concrete number of files to be compiled: An other project I'm working with is able to be compiled by the build bot when its build target contains 1384 files, but a commit where the target contains 1392 files is failing in the same way as this project: The number of files is less than here, but their file names are quite longer.
On my system
getconf ARG_MAX results in 262144, maybe the build bot is reaching this limit.