Galera 4 reprodicibility on i386 - help needed

[Chris Lamb]

Hi Otto,

> I would also like to request help with Galera 4, which fails to build
> in a reproducible way on i386 only:
> https://tests.reproducible-builds.org/debian/rb-pkg/unstable/i386/diffoscope-results/galera-4.html

This isn't, as far as I can tell, due to a build path issue. Rather,
I believe this occurs because the build system is looking for CRC
hardware support and is using different compiler flags as a result.
This is because we (deliberately) build with both an 32-bit and 64-bit
kernel, even on the Debian i386 architecture.

You can confirm this in the build logs:

  - Checking for hardware CRC support for x86_64
  - Hardwared CRC support enabled: -msse4.2
  + Checking for hardware CRC support for i686
  + No hardware CRC support

You should probably 'just' need to instruct the Debian build to not
perform this autodetection... or to simply ignore the result of it.
But you probably only want to do this on Debian i386 only — otherwise,
you prevent the hardware support from being activated elsewhere.

Looking at the logic of crc32c.cmake, I'm not entirely sure that
passing, for example, -DGU_CRC32C_NO_HARDWARE from debian/rules will
prevent -msse4.2 being added to the compiler... but I'm sure that
you'll be able to work that bit out, especially with upstream's
involvement.

Hope that helps.


Regards,

--
      ,''`.
     : :'  :     Chris Lamb
     `. `'`      lamby at debian.org 🍥 chris-lamb.co.uk
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