ci: Turn CentOS config into Alpine musl config

maflcko commented at 12:30 pm on September 25, 2025: member

Historically, the centos task was added to add CI coverage for old packages and 32-bit depends builds, but both are now covered by different tasks.

The CentOS task aligns with Ubuntu/Debian CI tasks in terms of libc usage, but (slightly) differs in package naming and update philosophy. I am not aware of the task ever discovering a centos-related issue, so it seems fine to recycle it into an Alpine Linux task.

The main difference would be that musl libc is now used. Also, busybox is used in Alpine, so in theory the busybox install could be removed from the arm CI task in the future.

Packaging considerations: All packages should roughly be the same (gcc remains at version 14, python remains at version 3.12, etc). Also, all packages are from the Alpine main track, coming with 2 years of support. The only exception is the py3-pip package (https://pkgs.alpinelinux.org/packages?name=py3-pip&branch=v3.22&repo=&arch=riscv64) from the community track, however, I don’t expect any issues arising from that.

ci: Turn centos config into alpine musl config fa6b2e9efe

DrahtBot added the label Tests on Sep 25, 2025

DrahtBot commented at 12:30 pm on September 25, 2025: contributor

The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.

Code Coverage & Benchmarks

For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/33480.

Reviews

See the guideline for information on the review process.

Type	Reviewers
ACK	janb84
Concept ACK	willcl-ark

If your review is incorrectly listed, please react with 👎 to this comment and the bot will ignore it on the next update.

Conflicts

Reviewers, this pull request conflicts with the following ones:

#31349 (ci: detect outbound internet traffic generated while running tests by vasild)

If you consider this pull request important, please also help to review the conflicting pull requests. Ideally, start with the one that should be merged first.

willcl-ark commented at 12:31 pm on September 25, 2025: member

Concept ACK

maflcko commented at 2:24 pm on September 25, 2025: member

Interesting side note: Looks like most unit tests are minimally faster on Alpine, except for the secp tests:

https://github.com/bitcoin/bitcoin/actions/runs/18007497948/job/51231174310?pr=33480#step:9:3415:

0148/150 Test   [#4](/bitcoin-bitcoin/4/): secp256k1_noverify_tests .............   Passed   38.88 sec
1149/150 Test   [#5](/bitcoin-bitcoin/5/): secp256k1_tests ......................   Passed   57.62 sec

https://github.com/bitcoin/bitcoin/actions/runs/18007193787/job/51230198016#step:9:2625 :

0145/150 Test   [#4](/bitcoin-bitcoin/4/): secp256k1_noverify_tests .............   Passed   12.96 sec
1148/150 Test   [#5](/bitcoin-bitcoin/5/): secp256k1_tests ......................   Passed   26.79 sec

janb84 commented at 2:48 pm on September 25, 2025: contributor

So Centos as CI task was not added to give good RHEL distro / Enterprise Linux support ?

maflcko commented at 3:18 pm on September 25, 2025: member

So Centos as CI task was not added to give good RHEL distro / Enterprise Linux support ?

No, as mentioned in the pull description. For reference, the history was:

#17635: Add centos 7 CI to check “old packages”.
#17900: Drop the “old packages” and use depends (32-bit).
#31651: Use native depends instead of 32-bit.
#31593: Bump to stream10, so that even the build system is using recent packages (gcc, cmake, python), to avoid warnings and errors. Also, …
#32560: … to be able to run a GCC hardened debug build with a recent GCC.

janb84 commented at 3:54 pm on September 25, 2025: contributor

Concept ACK fa6b2e9efece2d728bdc257c36c95db03e1a7bc4

This PR introduces more libc diversity in the CI pipeline (in the form of using Alpine), which is welcome.

Not completely agreeing with this PR sentence;

“So basically, the centos task is similar to all the Ubuntu/Debian CI tasks, possibly with some packages named slightly differently. "

Yes and No; (Risk of being too much of a nitpicker.)

Yes from a Libc perspective; Centos is glibc and Debian is also glibc
No from a distro philosophy; Ubuntu/Debian and RHEL distro’s are different in philosophy REHL is slower, more enterprise-focused. But do we need it as a CI step ? no as you mentioned, it does not give us new information.

There for this seems like a good improvement.

Also thanks for the extensive answer.

maflcko commented at 4:20 pm on September 25, 2025: member

nitpicker

No worries. Happy to adjust the pull description, if you have any suggestions I could take over.

maflcko commented at 5:05 pm on September 25, 2025: member

Also confirmed that the gcc debug mode works on alpine: https://github.com/maflcko/bitcoin-core-with-ci/actions/runs/18013008390/job/51250509812#step:8:2473 :

 0/usr/include/c++/14.2.0/debug/vector:508:
 1In function:
 2    constexpr std::debug::vector<_Tp, _Allocator>::reference std::
 3    debug::vector<_Tp, _Allocator>::operator[](size_type) [with _Tp = 
 4    CTxOut; _Allocator = std::allocator<CTxOut>; reference = CTxOut&; 
 5    size_type = long unsigned int]
 6
 7Error: attempt to subscript container with out-of-bounds index 3, but 
 8container only holds 3 elements.
 9
10Objects involved in the operation:
11    sequence "this" @ 0x7fffcfe17008 {
12      type = std::debug::vector<CTxOut, std::allocator<CTxOut> >;
13    }

janb84 commented at 8:26 am on September 26, 2025: contributor

nitpicker

No worries. Happy to adjust the pull description, if you have any suggestions I could take over.

How about something like this:

The CentOS task aligns with Ubuntu/Debian CI tasks in terms of libc usage, but (slightly) differs in package naming and update philosophy. I am not aware of the task ever discovering a centos-related issue, so it seems fine to recycle it into an Alpine Linux task.

maflcko commented at 8:29 am on September 26, 2025: member

thx, edited description

janb84 commented at 8:48 am on September 26, 2025: contributor

ACK fa6b2e9efece2d728bdc257c36c95db03e1a7bc4

This PR introduces more libc diversity in the CI pipeline (in the form of using Alpine), which is welcome.

DrahtBot requested review from willcl-ark on Sep 26, 2025

ci: Turn CentOS config into Alpine musl config #33480

Code Coverage & Benchmarks

Reviews

Conflicts