Improve null terminated lists handling

Author: mgreter

src/context.cpp

@@ -101,9 +101,12 @@ namespace Sass {
 
     // load plugins and register custom behaviors
     for(auto plug : plugin_paths) { plugins.load_plugins(plug); }
-    for(auto fn : plugins.get_headers()) { c_headers.push_back(fn); }
-    for(auto fn : plugins.get_importers()) { c_importers.push_back(fn); }
-    for(auto fn : plugins.get_functions()) { c_functions.push_back(fn); }
+    const std::vector<Sass_Importer_Entry> headers = plugins.get_headers();
+    const std::vector<Sass_Importer_Entry> importers = plugins.get_importers();
+    const std::vector<Sass_Function_Entry> functions = plugins.get_functions();
+    for(Sass_Importer_Entry fn : headers) { c_headers.push_back(fn); }
+    for(Sass_Importer_Entry fn : importers) { c_importers.push_back(fn); }
+    for(Sass_Function_Entry fn : functions) { c_functions.push_back(fn); }
 
     // sort the items by priority (lowest first)
     sort (c_headers.begin(), c_headers.end(), sort_importers);