C3 is a language designed as an evolution of C, without retaining strict backwards compatibility, but excellent interop with C.

This version brings - among other things: struct splatting (some_call(...a_struct, 1, 2)) and vector swizzle initialization (int[<3>] x = { .xy = 3, .z = 5 }). Together with other improvements and fixes.

Full change log:

Changes / improvements

• Improve multiline string parser inside compiler #2552.
• Missing imports allowed if module @if evaluates to false #2251.
• Add default exception handler to Win32 #2557.
• Accept "$schema" as key in project.json #2554.
• Function referencing in @return? for simplified fault declarations. Check @return? eagerly #2340.
• Enums now work with membersof to return the associated values. #2571
• Deprecated SomeEnum.associated in favour of SomeEnum.membersof
• Refactored @simd implementation.
• Improve error message for Foo{} when Foo is not a generic type #2574.
• Support @param directives for ... parameters. #2578
• Allow splatting of structs. #2555
• Deprecate --test-nocapture in favour of --test-show-output #2588.
• Xtensa target no longer enabled by default on LLVM 22, Compile with -DXTENSA_ENABLE to enable it instead
• Add float[<3>] x = { .xy = 1.2, .z = 3.3 } swizzle initialization for vectors. #2599
• Support int $foo... arguments. #2601
• Add musl support with --linux-libc=musl.

Fixes

• Foo.is_eq would return false if the type was a typedef and had an overload, but the underlying type was not comparable.
• Remove division-by-zero checks for floating point in safe mode #2556.
• Fix division-by-zero checks on a /= 0 and b /= 0f #2558.
• Fix fmod a %= 0f.
• Regression vector ABI: initializing a struct containing a NPOT vector with a constant value would crash LLVM. #2559
• Error message with hashmap shows "mangled" name instead of original #2562.
• Passing a compile time type implicitly converted to a typeid would crash instead of producing an error. #2568
• Compiler assert with const enum based on vector #2566
• Fix to Path handling c:\foo and \home parent. #2569
• Fix appending to c:\ or \ #2569.
• When encountering a foreach over a ZString* it would not properly emit a compilation error, but hit an assert #2573.
• Casting a distinct type based on a pointer to an any would accidentally be permitted. #2575
• overflow_* vector ops now correctly return a bool vector.
• Regression vector ABI: npot vectors would load incorrectly from pointers and other things. #2576
• Using defer catch with a (void), would cause an assertion. #2580
• Fix decl attribute in the wrong place causing an assertion. #2581
• Passing a single value to @wasm would ignore the renaming.
• *(int*)1 incorrectly yielded an assert in LLVM IR lowering #2584.
• Fix issue when tests encounter a segmentation fault or similar.
• With project.json, when overriding with an empty list the base settings would still be used. #2583
• Add sigsegv stacktrace in test and regular errors for Darwin Arm64. #1105
• Incorrect error message when using generic type that isn't imported #2589
• String.to_integer does not correctly return in some cases where it should #2590.
• Resolving a missing property on a const enum with inline, reached an assert #2597.
• Unexpected maybe-deref subscript error with out parameter #2600.
• Bug on rethrow in return with defer #2603.
• Fix bug when converting from vector to distinct type of wider vector. #2604
• $defined(hashmap.init(mem)) causes compiler segfault #2611.
• Reference macro parameters syntax does not error in certain cases. #2612
• @param name parsing too lenient #2614.

Stdlib changes

• Add CGFloat CGPoint CGSize CGRect types to core_foundation (macOS).
• Add NSStatusItem const enum to ns module (macOS).
• Add NSWindowCollectionBehavior NSWindowLevel NSWindowTabbingMode to ns module (macOS).
• Add ns::eventmask_from_type function to objc (macOS).
• Deprecate objc enums in favour of const inline enums backed by NS numerical types, and with the NS prefix, to better align with the objc api (macOS).
• Deprecate event_type_from function in favour of using NSEvent directly, to better align with the objc api (macOS).
• Add unit tests for objc and core_foundation (macOS).
• Make printing typeids give some helpful typeid data.
• Add NSApplicationTerminateReply to ns module (macOS).
• Add registerClassPair function to objc module (macOS).
• Somewhat faster BigInt output.
• Cache printf output.