Interesting that you would bring up Go. Go is probably the most head-desk language of all for writing portable code. Go will fight you the whole way.

Even plain C is easier.

You can have a whole file be for OpenBSD, to work around that some standard library parts have different types on different platforms.

So now you need one file for all platforms and architectures where Timeval.Usec is int32, and another file for where it is int64. And you need to enumerate in your code all GOOS/GOARCH combinations that Go supports or will ever support.

You need a file for Linux 32 bit ARM (int32/int32 bit), one for Linux 64 bit ARM (int64,int64), one for OpenBSD 32 bit ARM (int64/int32), etc…. Maybe you can group them, but this is just one difference, so in the end you'll have to do one file per combination of OS and Arch. And all you wanted was pluggable "what's a Timeval?". Something that all build systems solved a long time ago.

And then maybe the next release of OpenBSD they've changed it, so now you cannot use Go's way to write portable code at all.

So between autotools, cmake, and the Go method, the Go method is by far the worst option for writing portable code.

I have specifically given an example of u.h defining types such as i32, u64, etc to avoid running a hundred silly tests like "how long is long", "how long is long long", etc.

> So now you need one file for all platforms and architectures where Timeval.Usec is int32, and another file for where it is int64. And you need to enumerate in your code all GOOS/GOARCH combinations that Go supports or will ever support.

I assume you mean [syscall.Timeval]?

    $ go doc syscall
    [...]
    Package syscall contains an interface to the low-level operating system
    primitives. The details vary depending on the underlying system [...].