There’s a very large body of closed issues on most popular open source projects showing that “it compiles” is nowhere close to “it works.”

When you think about GNU autotools they're all about being able to compile on platforms that the software has never been compiled on before - that's why there are all those feature tests to see what the OS and compiler support.

I've done this many times on things like AIX 4.3 and HP-UX and so on. Sometimes you can get through the compile without any problems at all and the tool often works enough for your usecase and that's a win.

Sometimes there are particular little problems, sometimes it's something serious like an actual missing C library call or whatever and then you have to do some work. With nicely designed tools that have fairly wide support to begin with this tends to be easier.