On Tue, 2 Jul 2019, Jack Hill wrote:

>> Apparently these symbols were never supposed to be exported:
>> <https://github.com/libexpat/libexpat/pull/197>.  However, there could
>> be packages "in the wild" that uses these symbols and would silently
>> break with the grafted Expat.
>> 
>> IIUC the fix for CVE-2018-20843 is this commit:
>> <https://github.com/libexpat/libexpat/commit/11f8838bf99ea0a6f0b76f9760c43704d00c4ff6>.
>> 
>> I think it's better to graft a variant with only this patch to be on the
>> safe side.  Can you try that?
>
> Good idea. I didn't think to check. Yes, I can try to do that.
>
>> Could you also submit a second patch that adds GitHub as an additional
>> download location for the regular Expat package?  :-)
>
> I'll try that as well.

I've prepared the two attached patches that I believe implement Marius's 
proposed solution.

Thanks,
Jack