Exploring large codebase (unity build) compilation time

Intro &#xA; Previously I wrote a post about compiling inkscape&rsquo;s codebase using &ldquo;unity&#xA;build&rdquo; methods where all files that need to&#xA;be compiled are joined during preprosessing phase and then compiled as single&#xA;compilation unit. Compiling all that code in one go took from 3 to 6 minutes&#xA;depending on optimization parameters. I got some free time and want to…