MAX Nightly 26.3.0.dev2026040805 Released

Nightly
1

:astronaut: A new nightly version has been released! :astronaut:

See the quickstart guide for installation instructions: Quickstart | Modular

MAX changelog updates:

  • Setting MODULAR_MAX_UNINITIALIZED_READ_CHECK=true enables detection of
    uninitialized memory reads in Mojo kernels. InferenceSession automatically
    enables the debug allocator poison and compiles kernels with load-time
    poison checks for all float types. When a load matches a poison pattern,
    the process aborts with a descriptive message.
  • Added distributed.allreduce.sum op handler to the experimental eager
    interpreter, enabling multi-GPU eager execution of allreduce collectives
  • Added distributed.allgather op handler to the experimental eager
    interpreter, enabling multi-GPU eager execution of allgather collectives
    without falling back to compilation.

Mojo changelog updates:

  • [stdlib] Suppress abort message on Apple GPU
  • [stdlib] Implement IterableOwned for Span
  • [stdlib] Print abort message on GPU
  • [stdlib][MAX] Add uninitialized memory read detection for float loads

Raw MAX diff: https://github.com/modular/modular/compare/4ebbf94df7ce225199478a7204a474707631e25f...8d0e779b0699fffc9011e1579f9445ec4aaa657f)>
Current Mojo changelog: https://github.com/modular/modular/blob/main/mojo/docs/nightly-changelog.md