building the IDE within Eclipse

I followed the instructions here - Building Arduino · arduino/Arduino Wiki · GitHub and was able to build the ide. I had to install the 32-bit java 1.8 sdk as instructed. Now, I want to build the IDE project from eclipse 64-bit IDE. Is that possible?

yep, I make all my Arduino ports in Eclipse+CDT and GCC it is difficult to write instructions how to set eclipse(gcc) options

New C++ project Project properties: Set GCC path, folders, libraries search paths, linker script GCC C and C++ settings... and compile

I make all my Arduino ports in Eclipse+CDT and GCC

I believe that he's talking about building the IDE itself, not building Arduino Sketches. That means Java, and perhaps a bunch of other stuff (aren't some pieces written in go, these days?) I have no idea. If you really like the Eclipse editor and source-browsing features, I imagine you could get pretty far using the standard Eclipse Java environment, and then still use "ant" in the cli to do the actual (rather complex) build...