More bandaids to avoid #1309

Even though we only bind the shared_ptr in the after callback, the
worker thread was still copying the callback and therefore gaining
a shared reference. Here we try to eliminate the copies.

1 files changed, 4 insertions, 4 deletions

diff --git a/src/mbgl/util/thread.hpp b/src/mbgl/util/thread.hpp
index 415bda38d8..189182464c 100644
--- a/src/mbgl/util/thread.hpp
+++ b/src/mbgl/util/thread.hpp
@@ -49,14 +49,14 @@ public:
 
     // Invoke object->fn(args...) in the runloop thread, then invoke callback(result) in the current thread.
     template <typename Fn, class R, class... Args>
-    void invokeWithResult(Fn fn, std::function<void (R)> callback, Args&&... args) {
-        loop->invokeWithResult(std::bind(fn, object, args...), callback);
+    void invokeWithResult(Fn fn, std::function<void (R)>&& callback, Args&&... args) {
+        loop->invokeWithResult(std::bind(fn, object, args...), std::move(callback));
     }
 
     // Invoke object->fn(args...) in the runloop thread, then invoke callback() in the current thread.
     template <typename Fn, class... Args>
-    void invokeWithResult(Fn fn, std::function<void ()> callback, Args&&... args) {
-        loop->invokeWithResult(std::bind(fn, object, args...), callback);
+    void invokeWithResult(Fn fn, std::function<void ()>&& callback, Args&&... args) {
+        loop->invokeWithResult(std::bind(fn, object, args...), std::move(callback));
     }
 
     // Invoke object->fn(args...) in the runloop thread, and wait for the result.