Vix v0.2.0 Release Notes

Breaking Changes — This is a major language redesign release.

Syntax Changes

1. Removed global and const Keywords

Module-level let declarations now automatically have persistent storage duration (like globals). No special keyword is needed.

Before (v0.1.x):

global counter: i32 = 100
const MAX_SIZE = 1024
let const N = 10

After (v0.2.0):

let counter: i32 = 100
let MAX_SIZE = 1024

• Variables declared at module level with let are automatically global and persistent.
• Variables declared at function level with let are stack-local (as before).
• Use let mut for mutable variables at any scope.

2. Removed Auto-Generated main() Function

The compiler no longer auto-generates a main() function. You must define fn main() explicitly.

Before (v0.1.x):

print("hello")

After (v0.2.0):

fn main(): i32
{
    print("hello")
    return 0
}

If no fn main() is defined and #[no_main] is not set, the compiler will emit an error.

3. Variables Are Immutable by Default

All let declarations are now immutable by default. Use let mut to declare mutable variables.

let x = 10        // immutable
let mut y = 20    // mutable
y = 30            // OK

4. Function-Level Static Variables

For rare cases requiring static storage duration inside functions, use let static mut:

fn get_id(): i32
{
    let static mut id = 0
    id += 1
    return id
}

Bug Fixes

Windows Linker

• Fixed MinGW linker failing to find -lmoldname, -lpthread, -ladvapi32, -lshell32, -luser32 when the bundled libc/ directory is incomplete.
• Added automatic probing of Windows SDK and MSVC library paths.
• Libraries are now only linked if they are actually found on the system, preventing linker errors from missing optional libraries.

Migration Guide

1. Replace all global declarations with let.
2. Replace all const and let const declarations with let.
3. Replace all pub global declarations with let (add pub support for let in future releases).
4. Add fn main(): i32 { ... return 0 } to any file that previously relied on top-level code execution.
5. Add mut to any variable that needs to be reassigned.

Test Results

• 732/732 pytest tests passing
• 220/220 compilation tests passing
• 209/209 run tests passing