From: Tom Lane <tgl@sss.pgh.pa.us>
To: Thomas Munro <thomas.munro@gmail.com>
cc: Justin Pryzby <pryzby@telsasoft.com>,
        PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>,
        Andrew Dunstan <andrew@dunslane.net>
Subject: Re: Cygwin cleanup
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Comments: In-reply-to Thomas Munro <thomas.munro@gmail.com>
	message dated "Thu, 04 Aug 2022 17:19:47 +1200"
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Date: Thu, 04 Aug 2022 01:23:09 -0400
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Thomas Munro <thomas.munro@gmail.com> writes:
> It may be madness to try to work around this, but I wonder if we could
> use a static local variable that we update with atomic compare
> exhange, inside PG_SIGNAL_HANDLER_ENTRY(), and
> PG_SIGNAL_HANDLER_EXIT() macros that do nothing on every other system.
> On entry, if you can do 0->1 it means you are allowed to run the
> function.  If it's non-zero, set n->n+1 and return immediately: signal
> blocked, but queued for later.  On exit, you CAS n->0.  If n was > 1,
> then you have to jump back to the top and run the function body again.

And ... we're expending all this effort for what exactly?

			regards, tom lane