bug#23779: 25.0.95; consing "SHELLVAR" onto process-environment doesn't remove it from subprocess env

[Noam Postavsky]

On Fri, Jun 17, 2016 at 10:47 AM, Dmitry Gutov <dgutov@yandex.ru> wrote:
> On 06/17/2016 05:19 PM, Eli Zaretskii wrote:
>
>>> I wonder if we should make setenv work non-destructively now.
>>
>>
>> Why should we do that?  We have initial-environment if we need the
>> original value.
>
>
> Normally, we only want to change the environment for the duration of a
> command. So, what are the downsides?

process-environment could grow without bound. Only a serious problem
if some code calls setenv many times without let-binding
process-environment which is probably a mistake, but still there could
be code like that.