# CI Testing hangs on MacOS nightly

**URL:** <https://discourse.julialang.org/t/ci-testing-hangs-on-macos-nightly/133909>\
**Category:** Package Management\
**Tags:** testing\
**Created:** [November 16, 2025, 11:04am UTC](https://discourse.julialang.org/t/ci-testing-hangs-on-macos-nightly/133909 "2025-11-16T11:04:27Z")\
**Posts on this page:** 6\
**Page:** 1

<div class="post-metadata">

**Author:** ![TimG](https://avatars.discourse-cdn.com/v4/letter/t/82dd89/32.png) [@TimG](https://discourse.julialang.org/u/TimG)\
**Post date:** [November 16, 2025, 11:04am UTC](https://discourse.julialang.org/t/ci-testing-hangs-on-macos-nightly/133909/1 "2025-11-16T11:04:27Z")

</div>

How can I get any diagnostic information on why this one CI test seems to be hanging while all the others pass as expected?

```julia-auto
in progress checks
CI / Julia nightly - macOS-latest - default - pull_request (pull_request)Started 39 minutes ago — This check has started...

successful checks
CI / Documentation (pull_request)Successful in 1m
CI / Julia 1 - macOS-latest - default - pull_request (pull_request)Successful in 3m
CI / Julia 1 - ubuntu-latest - default - pull_request (pull_request)Successful in 5m
CI / Julia 1 - windows-latest - default - pull_request (pull_request)Successful in 6m
CI / Julia 1.8 - macOS-latest - default - pull_request (pull_request)Successful in 3m
CI / Julia 1.8 - ubuntu-latest - default - pull_request (pull_request)Successful in 4m
CI / Julia 1.8 - windows-latest - default - pull_request (pull_request)Successful in 4m
CI / Julia 1.9 - macOS-latest - default - pull_request (pull_request)Successful in 3m
CI / Julia 1.9 - ubuntu-latest - default - pull_request (pull_request)Successful in 3m
CI / Julia 1.9 - windows-latest - default - pull_request (pull_request)Successful in 4m
CI / Julia lts - macOS-latest - default - pull_request (pull_request)Successful in 3m
CI / Julia lts - ubuntu-latest - default - pull_request (pull_request)Successful in 3m
CI / Julia lts - windows-latest - default - pull_request (pull_request)Successful in 4m
CI / Julia nightly - ubuntu-latest - default - pull_request (pull_request)Successful in 6m
CI / Julia nightly - windows-latest - default - pull_request (pull_request)Successful in 6m
CI / Julia pre - macOS-latest - default - pull_request (pull_request)Successful in 4m
CI / Julia pre - ubuntu-latest - default - pull_request (pull_request)Successful in 5m
CI / Julia pre - windows-latest - default - pull_request (pull_request)Successful in 6m

codecov/patch — 95.89% of diff hit (target 93.46%)
codecov/project — 94.37% (+0.91%) compared to 168f7af

```

Clicking on the 3 dots to the right hand side and asking for more information gives

```julia-auto
Run julia-actions/julia-buildpkg@v1 40m 3s
Run echo "JULIA_PKG_SERVER_REGISTRY_PREFERENCE=${JULIA_PKG_SERVER_REGISTRY_PREFERENCE:-eager}" >> ${GITHUB_ENV}
Run if "false" == "false" && !isdir(DEPOT_PATH[1])

```

Also, how can I kill this - or will it time-out in the end?

(Edit: Just passed 1hr and still going…)

---

<div class="post-metadata">

**Author:** ![TimG](https://avatars.discourse-cdn.com/v4/letter/t/82dd89/32.png) [@TimG](https://discourse.julialang.org/u/TimG)\
**Post date:** [November 16, 2025, 3:14pm UTC](https://discourse.julialang.org/t/ci-testing-hangs-on-macos-nightly/133909/2 "2025-11-16T15:14:48Z")

</div>

I went out and it was still running 3 hours later when I came back.

I’ve manged to restart by adding a single blank line in the code of the PR, but the behaviour so far is the same.

The task that is hanging (`julia-actions/julia-buildpkg@v1`) ran in 3s on `Julia Pre - MacOS latest` and in 6s on `Julia 1 - MacOS latest`. It seems to be the task the builds the test environment, before even trying to run the package’s test suite.

I don’t have a Mac myself, so can’t explore this locally.

I don’t know how to kill the process, so it’s still running.

---

<div class="post-metadata">

**Author:** ![giordano](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/giordano/32/2166_2.png) [@giordano](https://discourse.julialang.org/u/giordano)\
**Post date:** [November 16, 2025, 4:08pm UTC](https://discourse.julialang.org/t/ci-testing-hangs-on-macos-nightly/133909/3 "2025-11-16T16:08:32Z")

</div>

We’ve seen this issue in other repos (I also mentioned it on Slack the other day), but I didn’t have the time to investigate

> [@TimG](#):
>
> I don’t have a Mac myself, so can’t explore this locally.

Yes, you can: [GitHub - mxschmitt/action-tmate: Debug your GitHub Actions via SSH by using tmate to get access to the runner system itself.](https://github.com/mxschmitt/action-tmate)

---

<div class="post-metadata">

**Author:** ![TimG](https://avatars.discourse-cdn.com/v4/letter/t/82dd89/32.png) [@TimG](https://discourse.julialang.org/u/TimG)\
**Post date:** [November 17, 2025, 9:45am UTC](https://discourse.julialang.org/t/ci-testing-hangs-on-macos-nightly/133909/4 "2025-11-17T09:45:34Z")

</div>

> [@giordano](#):
>
> Yes, you can: [GitHub - mxschmitt/action-tmate: Debug your GitHub Actions via SSH by using tmate to get access to the runner system itself.](https://github.com/mxschmitt/action-tmate)

I will look at this but on first inspection I don’t really understand it. Let’s see how I get on!

The test itself was cancelled when it timed out after 6hours last night. The message was as follows:

```julia-auto
Run julia-actions/julia-buildpkg@v1
Run echo "JULIA_PKG_SERVER_REGISTRY_PREFERENCE=${JULIA_PKG_SERVER_REGISTRY_PREFERENCE:-eager}" >> ${GITHUB_ENV}
Run if "false" == "false" && !isdir(DEPOT_PATH[1])

[1145] signal 2: Interrupt: 2
in expression starting at none:0
__psynch_cvwait at /usr/lib/system/libsystem_kernel.dylib (unknown line)
unknown function (ip: 0x0) at (unknown file)
__psynch_mutexwait at /usr/lib/system/libsystem_kernel.dylib (unknown line)
unknown function (ip: 0x0) at (unknown file)
Allocations: 1 (Pool: 1; Big: 0); GC: 0
Error: The operation was canceled.

```

> **For comparison, here is the output of the successful runs on MacOS (e.g. Julia 1)...**
>
> ```julia
> Run julia-actions/julia-buildpkg@v1
> Run echo "JULIA_PKG_SERVER_REGISTRY_PREFERENCE=${JULIA_PKG_SERVER_REGISTRY_PREFERENCE:-eager}" >> ${GITHUB_ENV}
> Run if "false" == "false" && !isdir(DEPOT_PATH[1])
> Installing known registries into `~/.julia`
> Added `General` registry to ~/.julia/registries
> Updating registry at `~/.julia/registries/General.toml`
> Installed InputBuffers ──────────────── v1.1.1
> Installed DataValueInterfaces ───────── v1.0.0
> Installed Tables ────────────────────── v1.12.1
> Installed XML ───────────────────────── v0.3.8
> Installed OrderedCollections ────────── v1.8.1
> Installed TranscodingStreams ────────── v0.11.3
> Installed ColorTypes ────────────────── v0.12.1
> Installed Colors ────────────────────── v0.13.1
> Installed ZipArchives ───────────────── v2.6.0
> Installed DataAPI ───────────────────── v1.16.0
> Installed ArgCheck ──────────────────── v2.5.0
> Installed FixedPointNumbers ─────────── v0.8.5
> Installed CodecZlib ─────────────────── v0.7.8
> Installed Reexport ──────────────────── v1.2.2
> Installed CodecInflate64 ────────────── v0.1.3
> Installed Preferences ───────────────── v1.5.0
> Installed TableTraits ───────────────── v1.0.1
> Installed Statistics ────────────────── v1.11.1
> Installed IteratorInterfaceExtensions ─ v1.0.0
> Installed PrecompileTools ───────────── v1.3.3
> Updating `~/work/XLSX.jl/XLSX.jl/Project.toml`
> [5ae59095] + Colors v0.13.1
> [aea7be01] + PrecompileTools v1.3.3
> [bd369af6] + Tables v1.12.1
> [72c71f33] + XML v0.3.8
> [49080126] + ZipArchives v2.6.0
> [56f22d72] ~ Artifacts ⇒ v1.11.0
> [ade2ca70] ~ Dates ⇒ v1.11.0
> [a63ad114] ~ Mmap ⇒ v1.11.0
> [de0858da] ~ Printf ⇒ v1.11.0
> [9a3f8284] ~ Random ⇒ v1.11.0
> [cf7118a7] ~ UUIDs ⇒ v1.11.0
> [4ec0a83e] ~ Unicode ⇒ v1.11.0
> Updating `~/work/XLSX.jl/XLSX.jl/Manifest.toml`
> [dce04be8] + ArgCheck v2.5.0
> [6309b1aa] + CodecInflate64 v0.1.3
> [944b1d66] + CodecZlib v0.7.8
> [3da002f7] + ColorTypes v0.12.1
> [5ae59095] + Colors v0.13.1
> [9a962f9c] + DataAPI v1.16.0
> [e2d170a0] + DataValueInterfaces v1.0.0
> [53c48c17] + FixedPointNumbers v0.8.5
> [0c81fc1b] + InputBuffers v1.1.1
> [82899510] + IteratorInterfaceExtensions v1.0.0
> [bac558e1] + OrderedCollections v1.8.1
> [aea7be01] + PrecompileTools v1.3.3
> [21216c6a] + Preferences v1.5.0
> [189a3867] + Reexport v1.2.2
> [10745b16] + Statistics v1.11.1
> [3783bdb8] + TableTraits v1.0.1
> [bd369af6] + Tables v1.12.1
> [3bb67fe8] + TranscodingStreams v0.11.3
> [72c71f33] + XML v0.3.8
> [49080126] + ZipArchives v2.6.0
> [56f22d72] ~ Artifacts ⇒ v1.11.0
> [ade2ca70] ~ Dates ⇒ v1.11.0
> [8f399da3] + Libdl v1.11.0
> [37e2e46d] + LinearAlgebra v1.12.0
> [a63ad114] ~ Mmap ⇒ v1.11.0
> [de0858da] ~ Printf ⇒ v1.11.0
> [9a3f8284] ~ Random ⇒ v1.11.0
> [ea8e919c] + SHA v0.7.0
> [fa267f1f] + TOML v1.0.3
> [cf7118a7] ~ UUIDs ⇒ v1.11.0
> [4ec0a83e] ~ Unicode ⇒ v1.11.0
> [e66e0078] + CompilerSupportLibraries_jll v1.3.0+1
> [4536629a] + OpenBLAS_jll v0.3.29+0
> [83775a58] + Zlib_jll v1.3.1+2
> [8e850b90] + libblastrampoline_jll v5.15.0+0
> 
> ```

Just to clarify, I’m making a [PR on XLSX.jl](https://github.com/felipenoris/XLSX.jl/pull/326), which is a package I don’t own. More specifically, I’m making a minor update on an existing PR of mine which previously passed all tests. I changed a very few lines - mostly (but not all) comments - and now I get this failure.

I will also try to back out these changes one at a time to see if any of them specifically is triggering the failure but, as I said before, I think this process hangs before it even gets to my code.

---

<div class="post-metadata">

**Author:** ![giordano](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/giordano/32/2166_2.png) [@giordano](https://discourse.julialang.org/u/giordano)\
**Post date:** [November 17, 2025, 8:41pm UTC](https://discourse.julialang.org/t/ci-testing-hangs-on-macos-nightly/133909/5 "2025-11-17T20:41:53Z")

</div>

> [@TimG](#):
>
> Just to clarify, I’m making a [PR on XLSX.jl](https://github.com/felipenoris/XLSX.jl/pull/326), which is a package I don’t own. More specifically, I’m making a minor update on an existing PR of mine which previously passed all tests. I changed a very few lines - mostly (but not all) comments - and now I get this failure.
> 
> I will also try to back out these changes one at a time to see if any of them specifically is triggering the failure but, as I said before, I think this process hangs before it even gets to my code.

I tried to explain this in my previous message, but perhaps it wasn’t clear enough: this issue has **nothing** to do with your code, it happens in all julia nightly jobs. _Something_ changed over the last ~week in either the Julia nightly build, or the macOS environment on GitHub Actions (but somehow only affecting only the nightly version of Julia?), someone will have to investigate it.

---

<div class="post-metadata">

**Author:** ![giordano](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/giordano/32/2166_2.png) [@giordano](https://discourse.julialang.org/u/giordano)\
**Post date:** [November 21, 2025, 10:25pm UTC](https://discourse.julialang.org/t/ci-testing-hangs-on-macos-nightly/133909/6 "2025-11-21T22:25:19Z")

</div>

> [@giordano](#):
>
> someone will have to investigate it.

I did it:

> <https://github.com/JuliaLang/julia/pull/60196>
>
> Reverts JuliaLang/julia#60105. Nightly builds of aarch64-darwin Julia hang at s…tartup on some systems, notably on GitHub Actions, making all nightly jobs timeout (after 6 hours...), see https://discourse.julialang.org/t/ci-testing-hangs-on-macos-nightly/133909 (previously reported on Slack at https://julialang.slack.com/archives/CPWJ5DGG1/p1763055610279379). See also https://github.com/julia-actions/julia-runtest/pull/155. The error message when the process receives a SIGTERM signal is
> \`\`\`
> in expression starting at none:0
> \_\_psynch\_cvwait at /usr/lib/system/libsystem\_kernel.dylib (unknown line)
> unknown function (ip: 0x0) at (unknown file)
> \_\_psynch\_mutexwait at /usr/lib/system/libsystem\_kernel.dylib (unknown line)
> unknown function (ip: 0x0) at (unknown file)
> Allocations: 1 (Pool: 1; Big: 0); GC: 0
> \`\`\`
> I can reliably reproduce it locally on a M1 box with MacOSX 12.6 21.6.0, I can provide more information as needed.
> 
> I bisected the issue to #60105. CC @xal-0 for your information.

I used a different system, but I’m pretty sure it would have been possible to find the offending commit also using tmate on GitHub Actions as I suggested above.