Hello, it has been a while since I last did a source build, but it was previously supported to build a NAND image for GL-AR300M. I cannot find it now. I am expecting to find it if I select Atheros AR7xxx/AR9xxx Target System, Subtarget Generic Devices with NAND Flash, but it does not show up as a target profile.
I supposed at first maybe you had decided to drop GL-AR300M routers from librecmc support, but I see it is still possible to select GL-AR300M as a non-NAND (generic) build.
Am attempting to build using source taken a few weeks ago from commit 00f213da7e.