Created attachment 6491 [details] failing gcc config On fedora 24 (gcc v6) I cannot build the gcc 4 or 5 toolchains with c++ support
This has already been fixed as part of commit 45ce84f1fe3174fdada4b9bc947be2ddfb8c92eb. This commit was not in Buildroot 2016.05, so if you're using Buildroot 2016.05, you should either upgrade to the latest Git master, or backport commit 45ce84f1fe3174fdada4b9bc947be2ddfb8c92eb on top of Buildroot 2016.05.