Loader: small exception safety tweak.

Cannot use make_unique because we are using a private constructor,
but the same reasoning applies.

Author: rpavlik

changes/sdk/mr.3475.gl.md

@@ -0,0 +1,4 @@
+---
+- pr.413.gh.OpenXR-SDK-Source
+---
+Improvement: Loader: Code cleanup and robustness improvements.

src/loader/api_layer_interface.cpp

@@ -422,9 +422,10 @@ XrResult ApiLayerInterface::LoadApiLayers(const std::string& openxr_command, uin
         }
 
         // Add this API layer to the vector
-        api_layer_interfaces.emplace_back(new ApiLayerInterface(manifest_file->LayerName(), layer_library, supported_extensions,
-                                                                api_layer_info.getInstanceProcAddr,
-                                                                api_layer_info.createApiLayerInstance));
+        std::unique_ptr<ApiLayerInterface> iface{new ApiLayerInterface(manifest_file->LayerName(), layer_library,
+                                                                       supported_extensions, api_layer_info.getInstanceProcAddr,
+                                                                       api_layer_info.createApiLayerInstance)};
+        api_layer_interfaces.emplace_back(std::move(iface));
 
         // If we load one, clear all errors.
         any_loaded = true;

src/loader/manifest_file.cpp

@@ -638,7 +638,8 @@ void RuntimeManifestFile::CreateIfValid(const Json::Value &root_node, const std:
     }
 
     // Add this runtime manifest file
-    manifest_files.emplace_back(new RuntimeManifestFile(filename, lib_path));
+    std::unique_ptr<RuntimeManifestFile> manifest{new RuntimeManifestFile(filename, lib_path)};
+    manifest_files.emplace_back(std::move(manifest));
 
     // Add any extensions to it after the fact, while handling any renamed functions
     manifest_files.back()->ParseCommon(runtime_root_node);
@@ -891,8 +892,9 @@ void ApiLayerManifestFile::CreateIfValid(ManifestFileType type, const std::strin
     }
 
     // Add this layer manifest file
-    manifest_files.emplace_back(
-        new ApiLayerManifestFile(type, filename, layer_name, description, api_version, implementation_version, library_path));
+    std::unique_ptr<ApiLayerManifestFile> manifest{
+        new ApiLayerManifestFile(type, filename, layer_name, description, api_version, implementation_version, library_path)};
+    manifest_files.emplace_back(std::move(manifest));
 
     // Add any extensions to it after the fact, while handling any renamed functions
     manifest_files.back()->ParseCommon(layer_root_node);