I'd suggest you to check the Yocto documentation since those questions seems to be more related to the Yocto Linux Image instead the Galileo Board. I'll recommend you this Yocto document: http://www.yoctoproject.org/docs/current/mega-manual/mega-manual.html. You could visit the following Yocto site as well to check other Yocto documentation: https://www.yoctoproject.org/documentation
Also, I'd suggest you these following threads where there are discussions about similar topics regarding the cross compiler toolchain that you might find useful:
In addition, I believe the BSP guide describes how to build toolchain for eglibc, not for uclibc. I'm looking this guide: Intel® Quark BSP Build Guide
Thanks for all the support. Yes I believe the cross- compiler is for eglibc. I am building eglibc image right now to verify this.
I still am confused with point 3.
BSP guide says that installing this can break other non yocto tools so please clarify me how I can have this tool chain on the server without affecting other build environment.
Yes that is true. This happens when you run the script. There is a suggestion to mitigate it in the Intel® Quark BSP Build Guide on page 8. Check below the suggestion provided in the documentation:
"The script above may change your environment significantly, thus breaking other, non-Yocto tools you might be using (including anything which uses Python). To mitigate, Intel recommends that you open one terminal session to source the Yocto environment and run make, and run all your other commands in other terminal sessions."
alternatively you may want to look into the Intel IoT devkit SD card image https://software.intel.com/en-us/iot/devkit / meta-intel-iot-devkit - Intel IoT Developer Kit metadata which comes with eglibc + uclibc (such that it can run the sketches from default Arduino IDE for Galileo).
As crosscompiler you can use the Eclipse IDE which allows to deploy sw to the target and also comes with a remote debugger preinstalled.
If you are sick and tired of all the high level tutorial about how to set up cross compilation tool chain, I have step by step guide on how to do so (literally, step-by-step, which means all the changing directory, untar, and downloading required packages, where to put them, which exact line to change to what). In my example I downloaded boost BSP package from open-embedded, and I showed where to put it, and what lines in recipe you should change.
Check out my tutorial: https://www.gitbook.com/book/schwannden/ndn-on-galileo/details
The problem with this detailed step-by-step guide is that it is best that you use the same operating system: Debian 7.8.