test: Move cluster_linearize.h contents into cluster_linearize namespace #35737

1. 
   hebasto commented at 6:21 PM on July 16, 2026: member

   Clang recently enabled -Wunused-template under -Wall (see https://github.com/llvm/llvm-project/pull/206123, https://github.com/llvm/llvm-project/pull/207848, https://github.com/llvm/llvm-project/pull/208001). Our codebase triggers some of these warnings.

   This PR:

   1. Avoids Clang's -Wunused-template warnings in src/test/util/cluster_linearize.h when building the bench_bitcoin and fuzz targets.

   2. Follows the C++ Core Guidelines: "SF.21: Don't use an unnamed (anonymous) namespace in a header".

   3. Drops [[maybe_unused]] annotations, which are no longer needed after changing the linkage from internal to external.

   Along with #35679, this resolves all instances of this warning in the test/bench/fuzz code.

   Another related change: https://github.com/bitcoin-core/minisketch/pull/102.

   ---

   Steps to reproduce on the master branch @ 70d9ec7f3d452789d04dce81dc02db0b3b778bb5:

   $ CXXFLAGS="-Wunused-template" cmake -B build -DCMAKE_C_COMPILER=clang -DCMAKE_CXX_COMPILER=clang++ -DBUILD_BENCH=ON
   $ cmake --build build -t test_bitcoin
   $ cmake --build build -t bench_bitcoin
   [19/62] Building CXX object src/bench/CMakeFiles/bench_bitcoin.dir/cluster_linearize.cpp.o
   In file included from /home/hebasto/dev/bitcoin/src/bench/cluster_linearize.cpp:9:
   /home/hebasto/dev/bitcoin/src/test/util/cluster_linearize.h:122:17: warning: unused function template 'Ser' [-Wunused-template]
     122 |     static void Ser(Stream& s, const DepGraph<SetType>& depgraph)
         |                 ^~~
   /home/hebasto/dev/bitcoin/src/test/util/cluster_linearize.h:286:6: warning: unused function template 'SanityCheck' [-Wunused-template]
     286 | void SanityCheck(const DepGraph<SetType>& depgraph)
         |      ^~~~~~~~~~~
   /home/hebasto/dev/bitcoin/src/test/util/cluster_linearize.h:383:6: warning: unused function template 'SanityCheck' [-Wunused-template]
     383 | void SanityCheck(const DepGraph<SetType>& depgraph, std::span<const DepGraphIndex> linearization)
         |      ^~~~~~~~~~~
   3 warnings generated.
   [62/62] Linking CXX executable bin/bench_bitcoin
   

2. DrahtBot added the label Tests on Jul 16, 2026
3. 
   DrahtBot commented at 6:21 PM on July 16, 2026: contributor

   <!--e57a25ab6845829454e8d69fc972939a-->

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

   <!--006a51241073e994b41acfe9ec718e94-->

   Code Coverage & Benchmarks

   For details see: https://corecheck.dev/bitcoin/bitcoin/pulls/35737.

   <!--021abf342d371248e50ceaed478a90ca-->

   Reviews

   See the guideline and AI policy for information on the review process.

   Type	Reviewers
   ACK	sedited, maflcko

   If your review is incorrectly listed, please copy-paste <code>&lt;!--meta-tag:bot-skip--&gt;</code> into the comment that the bot should ignore.

   <!--5faf32d7da4f0f540f40219e4f7537a3-->

4. test: Move cluster_linearize.h contents into cluster_linearize namespace

   This change:
   1. Avoids Clang's `-Wunused-template` warnings when building the
      `bench_bitcoin` or `fuzz` targets.
   2. Follows C++ Core Guidelines: "SF.21: Don't use an unnamed (anonymous)
      namespace in a header".
   3. Drops `[[maybe_unused]]` annotations, which are no longer needed
      after changing the linkage from internal to external.

   21b4b790e4
5. hebasto force-pushed on Jul 17, 2026
6. sedited approved
7. 
   sedited commented at 12:18 PM on July 21, 2026: contributor

   ACK 21b4b790e4884e1edef6ea8da589e71f1ceacde8

8. 
   fanquake commented at 10:15 AM on July 22, 2026: member

   cc @sipa

9. 
   fanquake commented at 11:15 AM on July 24, 2026: member

   Our codebase triggers some

   Do cdash builds expire? Looks like this link is a 404 now?

10. 
    hebasto commented at 11:35 AM on July 24, 2026: member

    Our codebase triggers some

    Do cdash builds expire? Looks like this link is a 404 now?

    Hmm... The project has the "Build Retention" option set to 30 days. Still poking with settings...

    cc @willcl-ark

11. 
    hebasto commented at 11:43 AM on July 24, 2026: member

    Our codebase triggers some

    Do cdash builds expire? Looks like this link is a 404 now?

    I've updated the link to point to a GHA job instead.

12. 
    hebasto commented at 11:27 AM on July 31, 2026: member

    Here are fresh build logs with the most recent Clang snapshot: https://github.com/hebasto/bitcoin-core-nightly/actions/runs/30602794844.

13. fanquake referenced this in commit b33a5b5767 on Aug 4, 2026
14. 
    maflcko commented at 9:00 AM on August 5, 2026: member

    lgtm ACK 21b4b790e4884e1edef6ea8da589e71f1ceacde8

    thx

15. maflcko added this to the milestone 32.0 on Aug 5, 2026
16. sedited merged this on Aug 5, 2026
17. sedited closed this on Aug 5, 2026

    ---

Milestone
32.0