Re: [ptxdist] Building x86_64 without host libs (e.g. zlib)

[Michael Olbrich <m.olbrich@pengutronix.de>]

On Fri, Jan 31, 2025 at 03:41:05PM +0000, John Graham wrote:
> I'm trying to build an x86_64 toolchain that's independent of the host. By
> default in the ptxconfigs/x86_64-unknown-linux-gnu_gcc config, it has e.g.
> `PTXCONF_HOST_SYSTEM_ZLIB=y`. I expected I could set this to `=n`, but when
> I do that, `ptxdist go` fails with:
> 
> ```
> 
> ptxdist: error: 'host-system-zlib' is not selected.
> ptxdist: error: This can happen if the ptxconfig is outdated or
> ptxdist: error: the package is disabled for the current architecture
> 
> ```
> 
> Can anyone tell me if this is the proper approach to disabling use of the
> host libraries, and/or what I'm doing wrong? Any help appreciated!

There are issues on multiple levels:

1. just changing the config file will not make the dependency go away. If
you look at the package rules in rules/ you'll see multiple ones that have
'select HOST_SYSTEM_ZLIB'. That's what is causing the error you're seeing.

2. Even if you remove those, building will probably fail. The dependency is
there for a reason. You would definitely need to remove the
--with-system-zlib that's there in several places. But I'm not sure, if
that's enough. It's quite possible that for some of the packages, zlib is
a hard requirement.

Why would you want to build without zlib anyways? It's not the only
requirement and removing just that seem odd.

Michael

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