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Title: Gentoo raises s390x baseline to z10
Author: Andreas K. Hüttel <dilfridge@gentoo.org>
Posted: xxxx-xx-xx
Revision: x
News-Item-Format: 2.0
Display-If-Profile: default/linux/s390/17.0/s390x
Display-If-Profile: default/linux/s390/17.0/s390x/systemd/merged-usr Display-If-Profile: default/linux/s390/23.0/split-usr/s390x
Display-If-Profile: default/linux/s390/23.0/s390x
Display-If-Profile: default/linux/s390/23.0/s390x/systemd

Since more and more software for s390x assumes the presence of a more
recent processor, we will raise in 64bit s390x profiles the ISA baseline
for the catalyst stage builds and the published binary packages from
z900 to z10 (i.e., -march=z10).

* If you are running an installation and emerge locally from source,
this does not affect you.

* If you are running an installation and use our binary packages,
please make sure you have compatibility for z10 or switch to building
from source.

* The 64bit s390x stages will only work with machines compatible with
z10.

* This does not affect the 31bit s390 stages or packages.

The z10 Enterprise Class (2097 series) was introduced in February 2008 [1], which essentially means everyone except hardware archaeologists should be
fine.

Note that z10 is still a very conservative setting; on modern machines
a newer ISA is strongly recommended.

[1] https://en.wikipedia.org/wiki/IBM_Z

--
Andreas K. Hüttel
dilfridge@gentoo.org
Gentoo Linux developer
(council, toolchain, base-system, perl, libreoffice)
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