This is a bug fix release. There are a few minor API changes. Making way for 3.2.0 work.

There are no documentation updates with this releases.

What's Changed

• Warning as error off by default by @erincatto in https://github.com/erincatto/box2d/pull/914
• functions to get and set surface material by @erincatto in https://github.com/erincatto/box2d/pull/921
• Fixed another shape distance assert by @erincatto in https://github.com/erincatto/box2d/pull/926
• Revolute and prismatic targets by @erincatto in https://github.com/erincatto/box2d/pull/929
• Cast initial overlap by @erincatto in https://github.com/erincatto/box2d/pull/933
• Tunable joint stiffness by @erincatto in https://github.com/erincatto/box2d/pull/934
• _aligned_free for mingw by @erincatto in https://github.com/erincatto/box2d/pull/939
• Removed MSVC static library setting by @erincatto in https://github.com/erincatto/box2d/pull/940

Full Changelog: https://github.com/erincatto/box2d/compare/v3.1.0...v3.1.1