diff --git a/docs/README-versions.md b/docs/README-versions.md new file mode 100644 index 000000000..097dba1c7 --- /dev/null +++ b/docs/README-versions.md @@ -0,0 +1,60 @@ +# Versioning + +## Since 2.23.0 + +SDL follows an "odd/even" versioning policy, similar to GLib, GTK, Flatpak +and older versions of the Linux kernel: + +* The major version (first part) increases when backwards compatibility + is broken, which will happen infrequently. + +* If the minor version (second part) is divisible by 2 + (for example 2.24.x, 2.26.x), this indicates a version of SDL that + is believed to be stable and suitable for production use. + + * In stable releases, the patchlevel or micro version (third part) + indicates bugfix releases. Bugfix releases should not add or + remove ABI, so the ".0" release (for example 2.24.0) should be + forwards-compatible with all the bugfix releases from the + same cycle (for example 2.24.1). + + * The minor version increases when new API or ABI is added, or when + other significant changes are made. Newer minor versions are + backwards-compatible, but not fully forwards-compatible. + For example, programs built against SDL 2.24.x should work fine + with SDL 2.26.x, but programs built against SDL 2.26.x will not + necessarily work with 2.24.x. + +* If the minor version (second part) is not divisible by 2 + (for example 2.23.x, 2.25.x), this indicates a development prerelease + of SDL that is not suitable for stable software distributions. + Use with caution. + + * The patchlevel or micro version (third part) increases with + each prerelease. + + * Each prerelease might add new API and/or ABI. + + * Prereleases are backwards-compatible with older stable branches. + For example, 2.25.x will be backwards-compatible with 2.24.x. + + * Prereleases are not guaranteed to be backwards-compatible with + each other. For example, new API or ABI added in 2.25.1 + might be removed or changed in 2.25.2. + If this would be a problem for you, please do not use prereleases. + + * Only upgrade to a prerelease if you can guarantee that you will + promptly upgrade to the stable release that follows it. + For example, do not upgrade to 2.23.x unless you will be able to + upgrade to 2.24.0 when it becomes available. + + * Software distributions that have a freeze policy (in particular Linux + distributions with a release cycle, such as Debian and Fedora) + should usually only package stable releases, and not prereleases. + +## Before 2.23.0 + +Older versions of SDL followed a similar policy, but instead of the +odd/even rule applying to the minor version, it applied to the patchlevel +(micro version, third part). For example, 2.0.22 was a stable release +and 2.0.21 was a prerelease. diff --git a/docs/README.md b/docs/README.md index fd0078a5c..d9953c08f 100644 --- a/docs/README.md +++ b/docs/README.md @@ -47,6 +47,7 @@ More documentation and FAQs are available online at [the wiki](http://wiki.libsd - [PSP](README-psp.md) - [Raspberry Pi](README-raspberrypi.md) - [Touch](README-touch.md) +- [Versions](README-versions.md) - [WinCE](README-wince.md) - [Windows](README-windows.md) - [WinRT](README-winrt.md)