Is this a bug or normal behavior of vs2013 initializer_list?
Yes to both. VS2013's std::initializer_list implementation is buggy; see similar questions Why first element is destroyed? and Double delete in initializer_list vs 2013.
Someone reported one of those issues to Microsoft in November 2013: http://connect.microsoft.com/VisualStudio/feedback/details/807419/initializer-lists-leaking-memory
This is now fixed in the Spring Update:
Bugs Fixed in Visual Studio 2013 Update 2
