Re: [PATCH] qapi: Fix crash on redefinition with a different condition

[Eric Blake]

On Fri, Aug 06, 2021 at 02:05:10PM +0200, Markus Armbruster wrote:
> QAPISchema._make_implicit_object_type() asserts that when an implicit
> object type is used multiple times, @ifcond is the same for all uses.
> It will be for legitimate uses, i.e. simple union branch wrapper
> types.  A comment explains this.
> 
> The assertion fails when a command or event is redefined with a
> different condition.  The redefinition is an error, but it's flagged
> only later.
> 
> Fixing the assertion would complicate matters further.  Not
> worthwhile, drop it instead.  We really need to get rid of simple
> unions.
> 
> Tweak test case redefined-event to cover redefinition with a different
> condition.
> 
> Signed-off-by: Markus Armbruster <armbru@redhat.com>
> ---

6.2 material (this corner case doesn't fire in our 6.1 code base, and
really only matters for developers adding new interfaces which won't
happen in 6.1).

Reviewed-by: Eric Blake <eblake@redhat.com>

-- 
Eric Blake, Principal Software Engineer
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