Fix can't compile features not_std and sync

Cargo.toml

@@ -27,7 +27,7 @@ bitflags = { version = "2.0.0", default-features = false }
 smartstring = { version = "1.0.0", default-features = false }
 rhai_codegen = { version = "2.1.0", path = "codegen" }
 
-no-std-compat = { git = "https://gitlab.com/jD91mZM2/no-std-compat", version = "0.4.1", default-features = false, features = ["alloc"], optional = true }
+no-std-compat = { git = "https://gitlab.com/jD91mZM2/no-std-compat", version = "0.4.1", default-features = false, features = ["alloc", "compat_sync"], optional = true }
 libm = { version = "0.2.0", default-features = false, optional = true }
 hashbrown = { version = "0.14.0", optional = true }
 core-error = { version = "0.0.0", default-features = false, features = ["alloc"], optional = true }

src/func/native.rs

@@ -534,20 +534,7 @@ pub fn locked_read<T>(value: &Locked<T>) -> Option<LockGuard<T>> {
 
     #[cfg(feature = "sync")]
     #[cfg(not(feature = "unchecked"))]
-    {
-        // Spin-lock for a short while before giving up
-        for _ in 0..10 {
-            match value.try_read() {
-                Ok(guard) => return Some(guard),
-                Err(std::sync::TryLockError::WouldBlock) => {
-                    std::thread::sleep(std::time::Duration::from_secs(1))
-                }
-                Err(_) => return None,
-            }
-        }
-
-        return None;
-    }
+    return value.try_read();
 }
 
 /// _(internals)_ Lock a [`Locked`] resource for mutable access.
@@ -565,20 +552,7 @@ pub fn locked_write<T>(value: &Locked<T>) -> Option<LockGuardMut<T>> {
 
     #[cfg(feature = "sync")]
     #[cfg(not(feature = "unchecked"))]
-    {
-        // Spin-lock for a short while before giving up
-        for _ in 0..10 {
-            match value.try_write() {
-                Ok(guard) => return Some(guard),
-                Err(std::sync::TryLockError::WouldBlock) => {
-                    std::thread::sleep(std::time::Duration::from_secs(1))
-                }
-                Err(_) => return None,
-            }
-        }
-
-        return None;
-    }
+    return value.try_write();
 }
 
 /// General Rust function trail object.

src/types/dynamic.rs

@@ -1701,7 +1701,7 @@ impl Dynamic {
                 #[cfg(not(feature = "sync"))]
                 Ok(value) => value.into_inner().flatten(),
                 #[cfg(feature = "sync")]
-                Ok(value) => value.into_inner().unwrap().flatten(),
+                Ok(value) => value.into_inner().flatten(),
                 // If there are outstanding references, return a cloned copy
                 Err(cell) => {
                     if let Some(guard) = crate::func::locked_read(&cell) {