-std=c++14 support for XCC compiler in Xtensa Xplorer

Hello,

      I am trying to do some program with Vision P5 DSP. where I have to use some typecasting of class members and also to use templates that all are supported with the flag -std=c++14. But the xcc is throwing error that it is an unknown flag. I need to know whether the -std=c++14 flag is available in any new updates of the tool or any similar flags to -std=c++14 is available for the compiler. 

Thanks in advance,

Indrajith