From mboxrd@z Thu Jan  1 00:00:00 1970
From: Jilles Tjoelker <jilles@stack.nl>
Subject: Re: Declaring local variables inside while loop leads to memory leak
Date: Tue, 26 Jul 2016 23:35:06 +0200
Message-ID: <20160726213506.GC16428@stack.nl>
References: <CAHRK1yP1GyUJEPNLSicUatRJPOJg=Oeac1daJkuJs6eDD+xi9Q@mail.gmail.com>
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To: Vladimir Didenko <vladimir.didenko@gmail.com>
Cc: dash@vger.kernel.org

On Tue, Jul 26, 2016 at 01:35:53PM +0300, Vladimir Didenko wrote:
> I found that declaring local variables inside while loop leads to
> memory leak. Code sample:

> test()
> {
>    while [ true ]; do
>       local a=
>    done
> }

> test

This can indeed consume a lot of memory. The memory is freed when the
function returns.

This could be fixed by adding a check before making a variable local but
that might make functions with many distinct locals slower.

Also note that the problem does not occur if local is used at the top of
a function only, as recommended by the man page.

-- 
Jilles Tjoelker