Due to the high amount of refactoring changes in develop, I have decided to target those to a new version branch 2.2.x.
There is also a lot of fixes and minor improvements, so those will be backported and released as 2.1.7.

To work around the #1708 issue (incompatibility with applications mis-using the zlib zalloc/zfree API), #1710 is merged instead of backporting the much bigger #1713.

Backported Changes

Buildsystem

• Generate CMake package configuration files #1647
• Relocate CMake target export definitions #1657
• Fix xsave intrinsic test for clang, and gcc 8.2 or newer, and icc #1664
• Disable Intel Compiler diagnostic message 10441 #1666
• Add missing checks for 64bit arm/intel with msvc compiler #1667
• Don't export git/github-related files in tar/zip archives #1688
• Add more result variables to the cmake package configuration #1671
• Fix building with NVHPC #1698
• CMake: Replace ; by $ in generator-expression #1707
• Bump max CMake policy version to 3.29.0 #1709
• make darwin cross compilation possible #1714

CI/Test

• Improve code coverage handling #1640 #1642 #1675 #1729
• Add VPCLMULQDQ crc32 tests to Google benchmarks #1651
• Add small compress() benchmark #1721 #1730
• Add back-and-forth inflateCopy() test #1731
• Enable orphaned unit tests for compare256_rle family of functions #1739
• Fix MSAN error in test_dict #1726
• CI workflows
  • Add dependabot for github actions #1687
  • Upgrade ilammy/msvc-dev-cmd to v1.13.0 #1665
  • Upgrade codecov/codecov-action to v4. #1676
  • Upgrade github/codeql-action from 2 to 3 #1691
  • Upgrade actions/upload-artifact from 3 to 4 #1692
  • Upgrade mymindstorm/setup-emsdk to v14. #1677
  • Update dependencies for 32-bit MinGW CI run #1711
  • Use windows-2019 for build with toolset v141 #1725
  • Fix macOS Github Actions #1720

Cleanup

• Removing some outdated comments #1655
• Remove obsolete TARGET_OS_MAC check #1703

Refactoring and Optimizations

• Remove unneeded pointer for functable.longest_match in deflate_slow #1633

ARM

• Add test for checking if -march=native needs -mfpu=neon for 32-bit ARM. #1683
• Override Clang x4 NEON intrinsics for Android #1694
• Add AArch64 feature detection support for OpenBSD #1732

Power

• Fix regression in Power8/9 detection #1649

RVV

• arch/riscv/riscv_features.c: fix uclibc build #1700
• Disable CodeCov for RISC-V as the toolchain doesn't support generating code coverage #1679

S390x

• IBM zSystems DFLTCC: Extend sanitizer checks #1717
• Update s390x dockerfile #1716

x86

• Fix PCLMULQDQ, AVX512VNNI and VPCLMULQDQ feature tests for Intel LLVM compiler (icx) #1672
• Fix invalid instruction usage in Xeon Phi x200 processors #1723

Misc

• free_aligned: validate passed in pointer #1710
• Sync changes with zlib 1.3.1 (LIT_MEM changes not included) #1654
• Improve Z_NULL compatibility with zlib #1736
• .gitattributes: Enforce LF line-endings on all non-binary files #1715