[jll63]

(Written by Claude Code, on behalf of @jll63.)

Follow-up to #144, which raised the declared minimum to 3.16 because the tests call target_precompile_headers. That command is the only thing that needs 3.16, and it is only an optimisation, so this PR goes back down to 3.13:

• cmake_minimum_required(VERSION 3.13...3.20) in the root CMakeLists.txt and in test/cmake_test/CMakeLists.txt.
• The shared precompiled header in test/CMakeLists.txt is used only when CMAKE_VERSION is at least 3.16. Older CMake builds the tests without it: slower, not different.

3.13 is also the lower bound Boost.CI now uses (boostorg/boost-ci 7d792d689, "Use CMake 3.13 as lower bound"): below it, CMake does not install the package config files.

Testing

CMake 3.13.0 (the Linux binary from cmake.org), standalone build against a Boost super-project checkout, GCC, Debug: configure, build of the tests target, and ctest: 215/215 tests pass, with no precompiled headers.

A configure of the same tree with a bare cmake_minimum_required(VERSION 3.13) under CMake 3.28 and -Wdev printed no policy warnings, so no policy introduced after 3.13 changes anything on that path. That was only exercised on Linux/GCC; the MSVC-specific paths were not.

Not tested: the Boost.CI Min. CMake job on this branch (it will now build CMake 3.13), and Windows.

🤖 Generated with Claude Code

[cppalliance-bot]

An automated preview of the documentation is available at https://145.openmethod.prtest3.cppalliance.org/libs/openmethod/doc/html/index.html

If more commits are pushed to the pull request, the docs will rebuild at the same URL.

2026-11-10 22:42:22 UTC

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.57%. Comparing base (b681217) to head (36ae0b7).
⚠️ Report is 26 commits behind head on develop.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop     #145   +/-   ##
========================================
  Coverage    92.56%   92.57%           
========================================
  Files           29       29           
  Lines         2314     2316    +2     
  Branches       699      699           
========================================
+ Hits          2142     2144    +2     
  Misses         111      111           
  Partials        61       61           

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