How to enable c11 on later versions of gcc?
The correct option is -std=c11.
However, it is not available in gcc 4.6. You need at least gcc 4.7 to have this option supported. In some older versions like gcc 4.6, the option -std=c1x was available with experimental (i.e., very limited) support of C11.
Note that the current version of gcc is gcc 8.2.
Just to let you know GCC 4.9.x has far more complete support than older versions. If you really need to use this feature, please switch to anything 4.8+Here is the support status -- https://gcc.gnu.org/wiki/C11Status