Re: Full rebuild required for aarch64

[nia <nia%NetBSD.org@localhost>]

On Thu, Oct 14, 2021 at 11:18:28AM -0700, Michael Cheponis wrote:
> ok, I'll byte: What is RELRO and MKPIE, and why does it force a
> build-release?
> 
> 
> On Thu, Oct 14, 2021 at 11:01 AM nia <nia%netbsd.org@localhost> wrote:
> 
> > Hi,
> >
> > I've enabled RELRO and MKPIE for aarch64 so update builds will not work,
> > you will need to do a full release build if you are updating from source.
> >
> > Thanks for the patience.
> >

In short, they are features for hardening ELF binaries.
The reason they require a full rebuild is that they cannot be enabled
selectively without introducing problems and must be applied to the
full tree.

More in-depth explanations of RELRO:

https://www.redhat.com/en/blog/hardening-elf-binaries-using-relocation-read-only-relro

and MKPIE:

https://en.wikipedia.org/wiki/Position-independent_code