Stream: git-wasmtime

Topic: wasmtime / issue #13981 Unchecked memory consumption with...

Wasmtime GitHub notifications bot (Jul 25 2026 at 19:42):

alexcrichton opened issue #13981:

This program:

      (module
        (memory (export "mem") 65536 65536 shared)
        (func (export "run") (param $end i32)
          (local $i i32)
          (block $done
            (loop $l
              (br_if $done (i32.ge_u (local.get $i) (local.get $end)))
              (drop (memory.atomic.wait32 (local.get $i) (i32.const 0) (i64.const 0)))
              (local.set $i (i32.add (local.get $i) (i32.const 4)))
              (br $l)
            )
          )
        )
      )

when invoked as:

$ wasmtime -Wshared-memory --invoke run foo.wat 1000000000

will consume an unbounded amount of memory allocating wait queues on addresses which are never cleaned up (within Wasmtime's ParkingSpot implementation)

Wasmtime GitHub notifications bot (Jul 25 2026 at 19:42):

alexcrichton added the wasm-proposal:threads label to Issue #13981.

Last updated: Jul 29 2026 at 05:03 UTC