Bug#1020559: libc6: After upgrading libc6 expr is crashing with "stack smashing detected"

[Vasudev Kamath <vasudev-debian@copyninja.info>]

> Hello Vasudev,
> ok, reverting back would explain reportbug using version 2.34-8.
> 
> But was this core taken at a time where all libc packages
> should have been at 2.35-1 ?
> Then I don't understand that "Module" line,
> which shows the build-id from 2.34-8.

Ah sorry I did coredumpctl debug post reverting the libc6. But core file attached is taken when actual 2.35 was installed.

> 
> And if I understand you right the stack smashing
> is from "autoreconf --version".
> But I could not find it executing any "expr" processes in my test VM.

Actually just invoking autoconf was crashing and just executing expr itself was also crashing. If needed I can install latest libc and provide any required information. Do let me know

Thanks and Regards 
Vasudev