Z:gnu-www-ja-gcc-exception-3.1-faq--9268f4-So, if you use GCC, with or wi/en

So, if you use GCC, with or without GPL-compatible enhancements, that would be an Eligible Compilation Process. If you only use GPL-incompatible compiler tools, that would be an Eligible Compilation Process as well. (It's not uncommon for people who build software for GNU/Linux to link against the GCC libraries even if they're using a different compiler.) However, if you used GCC in conjunction with GPL-incompatible software during the process of transforming high-level code to low-level code, that would not be an Eligible Compilation Process. This would happen if, for example, you used GCC with a proprietary plugin.