Fix compilation error on wasm (#549)

Fix compilation error on wasm

.github/workflows/ci.yml

@@ -55,6 +55,13 @@ jobs:
           CARGO_INCREMENTAL: 0
           RUSTFLAGS: "-C debuginfo=0 -D warnings"
 
+      - name: Check wasm
+        uses: actions-rs/cargo@v1
+        with:
+          command: check
+          target: wasm32-unknown-unknown
+          override: true
+
   clean:
     runs-on: ubuntu-latest
     steps:

crates/bevy_tasks/src/single_threaded_task_pool.rs

@@ -1,7 +1,6 @@
 use std::{
     future::Future,
     mem,
-    pin::Pin,
     sync::{Arc, Mutex},
 };
 
@@ -63,10 +62,12 @@ impl TaskPool {
         F: FnOnce(&mut Scope<'scope, T>) + 'scope + Send,
         T: Send + 'static,
     {
-        let executor = async_executor::LocalExecutor::new();
+        let executor = &async_executor::LocalExecutor::new();
+        let executor: &'scope async_executor::LocalExecutor<'scope> =
+            unsafe { mem::transmute(executor) };
 
         let mut scope = Scope {
-            executor: &executor,
+            executor,
             results: Vec::new(),
         };