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From: Stefan Monnier <monnier@iro.umontreal.ca>
To: emacs-devel@gnu.org
Subject: extract_data_from_object considered dangerous
Date: Sun, 22 Sep 2019 09:39:54 -0400	[thread overview]
Message-ID: <jwv5zlke9nx.fsf-monnier+emacs@gnu.org> (raw)

I was just looking at the calling convention of extract_data_from_object
and it seems intrinsically dangerous:

    It returns a char* into a Lisp_Object without associating it with
    any specific Lisp_Object

In some cases, the Lisp_Object into which the result points is freshly
allocated during the call, so once we return from the function, there is
no Lisp_Object reference to it anywhere any more to keep it from
being GC'd.


        Stefan




             reply	other threads:[~2019-09-22 13:39 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-09-22 13:39 Stefan Monnier [this message]
2019-09-22 16:50 ` extract_data_from_object considered dangerous Eli Zaretskii
2019-09-22 20:53   ` Stefan Monnier
2019-09-23  2:28     ` Eli Zaretskii

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