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Date: Sat, 3 Dec 2016 19:36:24 +0000
From: "Richard W.M. Jones" <rich@annexia.org>
To: immanuel litzroth <ilitzroth@gmail.com>
Cc: OCaML List Mailing <caml-list@inria.fr>
Message-ID: <20161203193624.GB28111@annexia.org>
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Subject: Re: [Caml-list] Raising invalid_argument with a constructed string.

On Sat, Dec 03, 2016 at 03:00:57PM +0100, immanuel litzroth wrote:
> Yes, I've used that solution too, keeping a static fixed string around,
> it's just not very nice and will break if it's ever multithreaded.

You shouldn't make the string static, and we do *not* do that in
libguestfs.  You should simply allocate it on the stack.  This is
thread safe.

Also on the bug it was stated:

> The stack-based solutions rely on guessing arbitrary size limits on
> the dynamic strings, which is often possibles but sometimes
> inconvenient/inelegant.

but this is not true either.  You can use alloca to allocate a
variable sized string on the stack.

As Xavier Leroy says, fixing this is not necessary, although there's
perhaps a usability argument.

Rich.