CMake FetchContent_Populate stalls forever on Cygwin as of recently

Daniel's Avatar


12 Dec, 2021 09:48 PM

Hello friends,

Until very recently (two weeks ago), everything was fine. We use CMake to build our C++ code, and within it, we use the FetchContent module to clone remote dependencies from Github (in particular, the Google Test framework).

As of recently, this step of the build now stalls forever with no output, see e.g.,

Strangely, however, this only happens when building inside of Cygwin. We have other jobs that use MSVS, and WSL, and an entire set of tests on Ubuntu that run on Github Actions, that all work perfectly. Only Cygwin builds on Appveyor are running into this issue. We have not pushed any changes to the Appveyor configuration recently, and indeed, even builds that previous succeeded as of two weeks ago are failing if re-ran. Was any change made to Appveyor since then that could have caused an issue? Or is it possible that something in Cygwin was changed in the last few weeks that could have been a problem?

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