fix build with -default +unstable

Fixes #842

Signed-off-by: Marc-Antoine Perennou <Marc-Antoine@Perennou.com>

Author: Keruspe

src/utils.rs

@@ -66,7 +66,7 @@ mod timer {
 
 #[cfg(any(feature = "unstable", feature = "default"))]
 pub(crate) fn timer_after(dur: std::time::Duration) -> timer::Timer {
-    #[cfg(not(target_os = "unknown"))]
+    #[cfg(all(not(target_os = "unknown"), feature = "default"))]
     once_cell::sync::Lazy::force(&crate::rt::RUNTIME);
 
     Timer::new(dur)
@@ -84,7 +84,7 @@ mod timer {
     pub(crate) struct Timer(futures_timer::Delay);
 
     impl Timer {
-        pub(crate) fn after(dur: std::time::Duration) -> Self {
+        pub(crate) fn new(dur: std::time::Duration) -> Self {
             Timer(futures_timer::Delay::new(dur))
         }
     }