Why does macports require a migration across major version bumps?

[Mojca Miklavec]

On 30 August 2017 at 03:01, Eitan Adler wrote:
> What is the underlying reason to require a reinstall across major
> versions? I did something silly/stupid/smart  and removed the check
> from libexec/macports/lib/macports1.0/macports.tcl and just did 'sudo
> port upgrade outdated' to rebuild the world. It got about 90% of the
> way through and only errored on a few expected
> broken-for-other-reasons ports.
>
> Obvious I'm down the deep hole of unsupported actions but I'm curious
> about what gets missed when someone does this?

It's hard or nearly impossible to tell. Most of the time everything
will work until you try to upgrade or install something new. Problems
might include:

- a port A that builds differently depending on OS version and another
port B that has certain expectations of A
- change of compiler, potentially incompatible cincompatible compiler