TestActionFail fails on ppc64el

[Curtis Hovey]

A commit in the last few days introduced a regression in the unit-tests for trust ppc64el. The TestActionComplete, TestActionEvents, and TestActionFail tests consistently fail: There are other failures that look more random.
    http://juju-ci.vapour.ws:8080/view/Juju%20Revisions/job/run-unit-tests-trusty-ppc64el/1649/consoleText

[Curtis Hovey (sinzui)]

The suspect commits are
d56adba Merge pull request #894 from johnweldon/api-impl-listall
c01219d Merge pull request #893 from axw/lp1364200-aptmirror-config

^ Neither of these look like a direct cause. Maybe they made the tests brittle?

[Curtis Hovey (sinzui)]

Attached is a log with of a run with just the common failures, which might help identify the true issue.

[John Weldon (johnweldon4)]

FWIW the first CI error seemed to be with a13bad5c which was pull request #902 from johnweldon/api-impl-listpending

I'm investigating, but I don't see a direct cause either.

[Katherine Cox-Buday (cox-katherine-e)]

Ran through git bisect and came up with this. Continuing my investigation.

3565683e2b82c3254f19654c6a1e3ad93376fbe3 is the first bad commit
commit 3565683e2b82c3254f19654c6a1e3ad93376fbe3
Author: John Weldon <email address hidden>
Date: Mon Sep 29 19:01:40 2014 -0700

    Actions API :: ListAll

    List all Actions associated with given ActionReceivers

    Address review comments

    update dependencies

:040000 040000 e9f1026fae6dd769d59820f33b105a1a70f2b4ec 644f1cd83836f31c495bee7f7574f3a4769f32b2 M api
:040000 040000 1a5e01b2541e6e24febe44ec5ef4cd933e849547 567e7041d6bf73716c03b89bd23fc814402aa2ed M apiserver
:100644 100644 762e62eee1b27d6410cd07d3e666c4442e5a71b5 ca46074a52acf6318b34b4e6023195d5961779e7 M dependencies.tsv
:040000 040000 347a3001d0dd8e612edc2a31cf6d47bf5df6068b be679863e7de5417b212c20540b49da9f1e7e684 M state

[Katherine Cox-Buday (cox-katherine-e)]

Receiving new error, but strangely doesn't look like a direct result of the change. Investigating side-effects.

action_test.go:90:
    c.Assert(err, gc.IsNil)
... value *params.Error = &params.Error{"unauthorized access", "permission denied"} ("permission denied")

[Katherine Cox-Buday (cox-katherine-e)]

So far, from what I can tell, there may be an issue with how gccgo performs reflection. In uniter_base.go::FinishActions(...) the argument passed in doesn't contain a usable tag. I'm iterating over this issue by running the following:

go test -compiler=gccgo github.com/juju/juju/api/uniter/... -gocheck.f TestActionComplete

[John Weldon (johnweldon4)]

The bug is a serialization difference between go and gccgo

It was introduced by switching from a string to an ActionTag, and the names.ActionTag has a composed type that is not exported: idPrefixer.

I will propose a fix to names.ActionTag and then update dependencies.tsv to resolve this issue.

[John Weldon (johnweldon4)]

Fix committed : https://github.com/juju/juju/pull/912