Odin Files

BREAKING Changes

• core:os has been replaced with our newly improved and rewritten v2, previously available at core:os/os2. The old core:os implementation will remain available at core:os/old until sometime in Q3 of 2026.

• Article on Moving Towards a New "core:os"

• core:sys/info previously retrieved all information before main was entered, using @(init), and exposed everything via globals. It now gathers more information on demand, and returns everything via accessors for a consistent API. Where practical - like cpu name + features - those values will be cached.

New Language Features

• for init; x in y {} style loops

New Compiler Improvements

• Stop silently ignoring unknown directives on an inline asm expression
• Do not allow duplicated #partial directives on switch statements
• Add broadcasting to strings (Fix [#1837])
• Improve LLVM version picking
• Fix name canonicalization for typed ranges in bit_set
• Fix bit_set parapoly specialization
• Fix separating of diverging procedure types from block statements
• Update Type_Info_Bit_Set to always record underlying type. Add runtime.type_info_underlying
• Fix [#6347]
• Fix [#6270]

New Packages

• core:crypto/ecdsa: Add ECDSA support

Package Improvements

• [BREAKING] core:os/os2 -> core:os integration
• [BREAKING] core:sys/info: Change API from globals to calls. Do as little work in @(init) as practical.
• Allow test names to be specified as a command line option for tests executable
• vendor:x11/xlib: Fix signature of XChangeWindowAttributes
• vendor:directx/d3d12: Added IGraphicsCommandList7 and fix access violation errors
• Minimize some internal depencies in the core packages, e.g. don't import core:mem just for mem.Allocator_Error
• vendor:box2d: Fix and try Git LFS
• core:log: Add support for js/wasm
• core:container/xar: Fixes and improvements
• core:container/pool: Fix parapoly type inference around address sanitization when using multiple Pool types
• core:container/handle_map: Improvement
• demo.odin Fix cross_3d typo
• core:encoding/hex: Add uppercase encoding
• core:bytes: Update comment on compare; add additional caller location propagation
• core:math/big: Clean up
• core:os: Fix silent failure in os.replace_path_separators if the separator was multi-byte
• Add additional tests
• core:sys/es: Fix build errors
• core:unicode/utf8: Fix utf-8 validation
• Vendor Wycheproof cryptographic tests under tests/core/
• Propagate allocator errors from certain unicode functions
• Fix some tools and examples after core:os update and using-stmt feature
• Fix typo in atomic.odin documentation
• core:os: Remove process_close and add process_terminate
• core:time: Correct 12-hour clock string
• Update Unicode specification
• vendor:curl: Fix what argument for url_set
• Small optimization for dynamic arrays
• vendor:miniaudio: Upgrade to 0.11.24
• core:container/priority_queue: Add example and tests
• core:text/regex: Fix \b handling in iterator
• vendor:sdl3: Update to 3.4.2
• Add bindings to allow custom hardware cursors
• core:nbio: Fix op reuse
• core:strings: Fix substring not returning end of range
• core:sys/windows: Add more win32 API bindings
• core:sys/windows: Fix incorrect PVOID/VOID use in some signatures
• core:sys/windows: Tighten up MultiByteToWideChar usage in utf8_to_wstring_buf
• vendor:stb/vorbis: Remove unnecessary core:c/libc import
• vendor:wasm/WebGL: Add bindings, fix Tex*Image*D
• core:os: Return .Permission_Denied for .EACCES in Posix and Linux
• core:crypto/_blake2: Fix final blocks call with partial block
• Kill deprecated file tags and fix assignment of package docs

Full Change Log

Full Changelog: https://github.com/odin-lang/Odin/compare/dev-2026-02...dev-2026-03