http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59867
--- Comment #10 from Ed Smith-Rowland <3dw4rd at verizon dot net> --- Right now, -std=c++1y means anything after c++11. Does anyone have an idea about what happens when C++14 and these other TSen actually come out? I guess I was thinking as far as this extension is concerned: 1) It is left *on* for c++1y and gnu++1y for backward compatibility. Sigh. 2) It is *on* with gnu++14 as an extension. 3) It is *off* with c++14 for strict ANSI compatibility. 4) It is maybe on for c++17 and gnu++17 when & if it ever gets in. We seem to have dynamically sized array (VLA) in this category as well.