async-task excessive monomorphization example (https://github.com/smol-rs/async-task/issues/66)

Cargo.toml

[package]
name = "async-task-stresstest"
version = "0.1.0"
edition = "2021"

[dependencies]
# Apply the provided patch to the local copy of async-task.
async-task = {path = "../../async-task"}

main.rs

fn main() {
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
    let (_, _) = async_task::spawn(async move {}, |_| {});
}

remove_future_boxing.patch

diff --git a/src/runnable.rs b/src/runnable.rs
index 8b1b062..b413d58 100644
--- a/src/runnable.rs
+++ b/src/runnable.rs
@@ -6,7 +6,7 @@ use core::ptr::NonNull;
 use core::sync::atomic::Ordering;
 use core::task::Waker;
 
-use alloc::boxed::Box;
+//use alloc::boxed::Box;
 
 use crate::header::Header;
 use crate::raw::RawTask;
@@ -513,16 +513,7 @@ impl<M> Builder<M> {
         M: 'a,
     {
         // Allocate large futures on the heap.
-        let ptr = if mem::size_of::<Fut>() >= 2048 {
-            let future = |meta| {
-                let future = future(meta);
-                Box::pin(future)
-            };
-
-            RawTask::<_, Fut::Output, S, M>::allocate(future, schedule, self)
-        } else {
-            RawTask::<Fut, Fut::Output, S, M>::allocate(future, schedule, self)
-        };
+        let ptr = { RawTask::<Fut, Fut::Output, S, M>::allocate(future, schedule, self) };
 
         let runnable = Runnable {
             ptr,