Bug#940679: pandas: FTBFS on amd64 - TestDatetimelikeSubtype::test_astype_category[index3] crash

[Gianfranco Costamagna]

Hello,
On Thu, 19 Sep 2019 11:41:22 +0200 Graham Inggs <ginggs at debian.org> wrote:
> Hi Rebecca
> 
> On 2019/09/18 23:51, Rebecca N. Palmer wrote:
> > Was your local build on a different architecture, or must this be 
> > something random / hardware-or-environment-dependent / a very recent 
> > change in a build-dependency?
> 
> I first ran into a problem with the arch:all build of 0.23.3+dfsg-5 [1].
> 
> This seemed to be upstream issue #24088 [2], so I tested a src:all build 
> including the patch on barriere.debian.org.
> 
> This should have been caught by the autopkgtest, but I noticed that 
> python3-statsmodels was missing from the test dependencies.
> 
> After the build was successful on barriere, I uploaded with both changes.
> 
> At this point, I should have filed a bug against statsmodels to prevent 
> the migration of 0.9.0-5 to testing, but was expecting the pandas builds 
> to go smoothly.
> 
> I see 0.23.3+dfsg-6 was given back on amd64, and has just built 
> successfully.  I'll keep an eye on the arch:all build, and investigate 
> further if needed.


I think there is a chicken-and-egg problem now, on arch:all.

There should be a python3-pandas old binary around to satisfy the arch:all build-deps, but for some reasons it is not being picked up by the builders, and even in a local chroot.

apt-cache policy python3-pandas
python3-pandas:
  Installed: (none)
  Candidate: (none)
  Version table:

Fetched 377 kB in 2s (228 kB/s)
Reading package lists... Done
Reading package lists... Done
Building dependency tree       
Reading state information... Done
Package python3-pandas is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source

E: Package 'python3-pandas' has no installation candidate


My suggestion is:

1) create an amd64 sid chroot
2) install python3-pandas there
3) install build-dependencies
4) dpkg-buildpackage -A
5) sign & upload

after the package is installed, a source-only upload is required to let the migration happen, since arch:all binNMUs are not a thing (yet).

This should unblock the migration.

G.