2 files changed, 8 insertions, 11 deletions

diff --git a/core/io/resource_loader.cpp b/core/io/resource_loader.cpp
index a27341dd2c..f852e8d382 100644
--- a/core/io/resource_loader.cpp
+++ b/core/io/resource_loader.cpp
@@ -1136,10 +1136,7 @@ void ResourceLoader::initialize() {}
 void ResourceLoader::finalize() {}
 
 ResourceLoadErrorNotify ResourceLoader::err_notify = nullptr;
-void *ResourceLoader::err_notify_ud = nullptr;
-
 DependencyErrorNotify ResourceLoader::dep_err_notify = nullptr;
-void *ResourceLoader::dep_err_notify_ud = nullptr;
 
 bool ResourceLoader::create_missing_resources_if_class_unavailable = false;
 bool ResourceLoader::abort_on_missing_resource = true;
diff --git a/core/io/resource_loader.h b/core/io/resource_loader.h
index ffe9d5de9a..592befb603 100644
--- a/core/io/resource_loader.h
+++ b/core/io/resource_loader.h
@@ -89,8 +89,8 @@ public:
 
 VARIANT_ENUM_CAST(ResourceFormatLoader::CacheMode)
 
-typedef void (*ResourceLoadErrorNotify)(void *p_ud, const String &p_text);
-typedef void (*DependencyErrorNotify)(void *p_ud, const String &p_loading, const String &p_which, const String &p_type);
+typedef void (*ResourceLoadErrorNotify)(const String &p_text);
+typedef void (*DependencyErrorNotify)(const String &p_loading, const String &p_which, const String &p_type);
 
 typedef Error (*ResourceLoaderImport)(const String &p_path);
 typedef void (*ResourceLoadedCallback)(Ref<Resource> p_resource, const String &p_path);
@@ -218,24 +218,24 @@ public:
 	static void set_timestamp_on_load(bool p_timestamp) { timestamp_on_load = p_timestamp; }
 	static bool get_timestamp_on_load() { return timestamp_on_load; }
 
+	// Loaders can safely use this regardless which thread they are running on.
 	static void notify_load_error(const String &p_err) {
 		if (err_notify) {
-			err_notify(err_notify_ud, p_err);
+			callable_mp_static(err_notify).bind(p_err).call_deferred();
 		}
 	}
-	static void set_error_notify_func(void *p_ud, ResourceLoadErrorNotify p_err_notify) {
+	static void set_error_notify_func(ResourceLoadErrorNotify p_err_notify) {
 		err_notify = p_err_notify;
-		err_notify_ud = p_ud;
 	}
 
+	// Loaders can safely use this regardless which thread they are running on.
 	static void notify_dependency_error(const String &p_path, const String &p_dependency, const String &p_type) {
 		if (dep_err_notify) {
-			dep_err_notify(dep_err_notify_ud, p_path, p_dependency, p_type);
+			callable_mp_static(dep_err_notify).bind(p_path, p_dependency, p_type).call_deferred();
 		}
 	}
-	static void set_dependency_error_notify_func(void *p_ud, DependencyErrorNotify p_err_notify) {
+	static void set_dependency_error_notify_func(DependencyErrorNotify p_err_notify) {
 		dep_err_notify = p_err_notify;
-		dep_err_notify_ud = p_ud;
 	}
 
 	static void set_abort_on_missing_resources(bool p_abort) { abort_on_missing_resource = p_abort; }