C++14 support: xtensa-gcc

platform = espressif8266
board = nodemcuv2
framework = arduino
;build_unflags = -Os -std=gnu++11
build_flags = -std=c++14 -O3

this is my platformio.ini. It does not recognize the c++14 flag.

xtensa-lx106-elf-g++: error: unrecognized command line option ‘-std=c++14’

What version of gcc is exactly used here by PlatformIO? Is C++14 even supported?

GitHub - jcmvbkbc/gcc-xtensa: gcc for xtensa anyone knows what standard is supported?

See Service End for Bintray, JCenter, GoCenter, and ChartCenter | JFrog

Late to the game, but I too would like to know whether C++14 can be supported on esp8266 - the bintray link is now a 404.

UPDATE - Ah, this post seems to indicate it’s not an option.