Prepare for release with Boost 1.86

[striezel]

Seeing that the last Boost release with changes in GIL was Boost 1.80.0 in August 2022 and seeing that some fixes and features have landed on the develop branch during that time, it is probably a good time to perform the next true merge of develop into master to prepare for the next release of GIL / Boost.

Steps:

1. Merge (@mloskot?)
2. Build locally before git push (optional, because the CI should catch any errors)
3. Push
4. Review CI status
5. Collect release notes to RELEASES.md (see docs: Add release notes for Boost 1.86 #749)
6. Copy release notes to https://github.com/boostorg/website/ (Add release notes for GIL in Boost 1.86.0 website#844)

Changes

Below is an initial log of commits that will get merged from current develop into master for release with Boost 1.86 (as of 30 June 2024):

git log origin/master..develop --reverse --pretty=format:" | %cs | [%h](http://github.com/boostorg/gil/commit/%H) | %s |" | nl | sed -E 's/^\s/\|/g'

#	Date	Hash	Subject
1	2022-08-10	8465d5463	ci: partially replace Ubuntu 18.04 on GHA with Ubuntu 20.04 (#716)
2	2022-08-12	1f89d622e	ci: replace macOS 10.15 with macOS 11 in CI pipelines (#717)
3	2022-10-05	135edcfad	docs: Support newer version of Sphinx (#719)
4	2022-10-06	3f7daa99b	docs: Fix HTML syntax
5	2022-11-14	1df8c2407	ci: Update actions/checkout in GitHub Actions workflows to v3 (#720)
6	2023-02-07	712b827ed	fix: Convolution in convolve_2d (#723)
7	2023-02-07	d6e67f38c	fix: Normalize Gaussian 2D kernel. (#725)
8	2023-02-21	8f4cdcbcc	fix: Fixed custom color converter in dynamic_factory and added corresponding (#726)
9	2023-02-22	ecea33a90	fix: Make locator.hpp self contained (#729)
10	2023-03-16	eabd679f6	fix: Documentation (#731)
11	2023-10-01	e24c87fde	ci: ubuntu-18.04 environment is deprecated (#738)
12	2023-12-25	3a4d45443	ci: update actions/checkout in GitHub Actions workflows to v4 (#739)
13	2023-12-25	822c19ee7	ci: fix Python package in coverage workflow (#740)
14	2024-01-27	322c4e2e1	Updated Boost.Filesystem usage. (#741)
15	2024-04-18	2c3ee866b	Portable minmax Win32-API workaround #744 (#745)
16	2024-05-10	4fec872fe	feat: Guard boost::filesystem usage (#743)
17	2024-05-13	abb561a22	fix: Wrong buffer size in path string conversion functions (#746)
18	2024-05-17	481b6e7c1	feat: add tell() and error() functions to istream + ostream devices (#747)

(If this looks familiar, then because it was shamelessly copied from #667, the issue for the Boost 1.80 release.)

Timeline

According to the calender on https://www.boost.org/community/index.html the following dates are relevant for the release:

Date	Subject	Description
2024-06-24	Boost 1.86.0 closed for new libraries and breaking changes	Release branch is closed for new libraries and breaking changes to existing libraries. Still open for bug fixes and other routine changes to all libraries without release manager review.
2024-07-03	Boost 1.86.0 closed for major changes	Release closed for major code changes. Still open for serious problem fixes and docs changes without release manager review.
2024-07-10	Boost 1.86.0 closed for beta	Release closed for all changes
2024-07-17	Boost 1.86.0 beta	Beta posted for download.
2024-07-18	Boost 1.86.0 open for bug fixes	Release open for bug fixes and documentation updates. Other changes by permission of a release manager.
2024-08-07	Boost 1.86.0 closed	Release closed for all changes
2024-08-14	Boost 1.86.0 release	Release posted for download.

We are already past the first date in that list, but a first glance at the commit list above shows no obvious breaking changes, so it probably is still fine. There are still a few days left before the beta is closed for major changes, so we should still be able to get the changes from develop in right in time before the beta.

[mloskot]

Preparing for merge

git switch master
cd libs/gil
git switch develop
../../b2 cxxstd=14 test

All tests passed.

[mloskot]

Merge

$ git merge --no-ff develop
Merge made by the 'ort' strategy.
 .azure-pipelines.yml                                             | 71 -----------------------------------------------------------------------
 .ci/azure-pipelines/steps-check-cmake.yml                        |  9 ---------
 .ci/azure-pipelines/steps-cmake-build-and-test.yml               | 51 ---------------------------------------------------
 .ci/azure-pipelines/steps-install-boost.yml                      | 41 -----------------------------------------
 .ci/azure-pipelines/steps-install-conan.yml                      | 17 -----------------
 .ci/azure-pipelines/steps-install-gcc.yml                        | 18 ------------------
 .github/workflows/ci.yml                                         | 48 +++++++++++++++++++++++++++++++-----------------
 .github/workflows/coverage.yml                                   |  5 ++---
 .github/workflows/docs.yaml                                      |  2 +-
 CMakeLists.txt                                                   | 26 ++++++++++++++++++++++----
 README.md                                                        |  8 ++++----
 RELEASES.md                                                      | 23 +++++++++++++++++++++++
 doc/_static/boost.css                                            | 19 +++++++++++++++++++
 doc/_templates/layout.html                                       |  3 +++
 doc/design/dynamic_image.rst                                     |  6 +++---
 doc/io.rst                                                       |  6 ++++--
 include/boost/gil/detail/math.hpp                                |  2 +-
 include/boost/gil/extension/dynamic_image/image_view_factory.hpp | 20 ++++++--------------
 include/boost/gil/extension/histogram/std.hpp                    |  4 ++--
 include/boost/gil/extension/io/tiff/detail/read.hpp              |  6 +++---
 include/boost/gil/histogram.hpp                                  | 12 ++++++------
 include/boost/gil/image_processing/convolve.hpp                  |  2 +-
 include/boost/gil/image_processing/histogram_equalization.hpp    |  8 ++++----
 include/boost/gil/image_processing/histogram_matching.hpp        |  8 ++++----
 include/boost/gil/image_processing/numeric.hpp                   | 15 ++++++++++-----
 include/boost/gil/io/device.hpp                                  | 33 ++++++++++++++++++++++++++++++++-
 include/boost/gil/io/path_spec.hpp                               | 23 +++++++++++++++--------
 test/core/image_processing/convolve_2d.cpp                       | 93 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 test/core/image_processing/simple_kernels.cpp                    | 17 ++++++++++-------
 test/extension/dynamic_image/image_view_factory.cpp              | 67 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 test/extension/io/png/png_file_format_test.cpp                   |  6 +++---
 31 files changed, 369 insertions(+), 300 deletions(-)
 delete mode 100644 .azure-pipelines.yml
 delete mode 100644 .ci/azure-pipelines/steps-check-cmake.yml
 delete mode 100644 .ci/azure-pipelines/steps-cmake-build-and-test.yml
 delete mode 100644 .ci/azure-pipelines/steps-install-boost.yml
 delete mode 100644 .ci/azure-pipelines/steps-install-conan.yml
 delete mode 100644 .ci/azure-pipelines/steps-install-gcc.yml

Post-merge build

Locally, on Linux with GCC 14

cd libs/gil
../../b2 cxxstd=14 test
../../b2 cxxstd=14 variant=release address-model=64 test ## double check

All tests passed.

[mloskot]

Merge of develop to master pushed.

/cc @striezel @sdebionne

[striezel]

Thank you.

The merge happened before the beta is closed, so people will have the chance to test these changes when the beta is posted for download. :)

By the way, the CI on the master branch passed, so I marked the task "Review CI status" as done.

[mloskot]

I think this issue has been complete, hasn't it? And, thanks to your priceless help @striezel, we are good to be released with Boost 1.86, aren't we?

https://github.com/boostorg/gil/milestones/Boost%201.86 still lists numerous open PR-s/issues but those are drafts or unfinished work, so those will be moved to another milestone.

[marco-langer]

I think that I also have some open PRs / drafts which are older than 1-2 years.

I will have a look at them and close them if I think they will be never finished.

[mloskot]

@marco-langer We all have unfinished projects out there, so please don't worry about closing any of your PR-s. If we keep them open, that may catch an eye of a contributor who would be interested to pick up and continue any unfinished work.

[striezel]

I think this issue has been complete, hasn't it? And, thanks to your priceless help @striezel, we are good to be released with Boost 1.86, aren't we?

Yes, the issue is completed and GIL bsically is in a good shape for the release of Boost 1.86.0. I'll close the issue.

https://github.com/boostorg/gil/milestones/Boost%201.86 still lists numerous open PR-s/issues but those are drafts or unfinished work, so those will be moved to another milestone.

Maybe. The Boost 1.86.0 beta is closed for changes (in my timezone it's already 2024-07-10) and will be posted for download next week.

However, there will still be a few weeks time after that for bugfixes and documentation changes. Maybe some of the issues of that milestone will get fixed during that time. In that case another true merge from develop to master branch would be required before the release is closed for all changes. For example, I still would like to get the changes from #751 into Boost 1.86.0, because there are some awkward typos in there. 😆

[mloskot]

My apologies for no reaction, summer holidays period is not the best time for attending releases.

[striezel]

My apologies for no reaction

Don't worry. I think all the important stuff (that is, bugfixes and features) got merged in time before the 1.86 release. And for the rest there's always the next release.