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Date: Wed, 4 Nov 2015 12:43:21 +0000
From: "Richard W.M. Jones" <rich@annexia.org>
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Subject: [Caml-list] Are refs volatile?

Some code I wrote recently does:

  let quit = ref false in
  let set_quit _ = quit := true in
  Sys.set_signal Sys.sigint (Sys.Signal_handle set_quit);
  Sys.set_signal Sys.sigquit (Sys.Signal_handle set_quit);

and later on (where `tasks' is a list of long-running tasks):

  List.iter (
    fun task ->
      if not !quit then task ();
  ) tasks;

This works fine.  My question is, could a change to the compiler in
future cause the reference to !quit to be optimized away?  And if so,
is there a way to mark it as "volatile" (in the C sense)?

Rich.

-- 
Richard Jones
Red Hat