From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Eisentraut <peter.eisentraut@enterprisedb.com>
cc: Jacob Champion <pchampion@vmware.com>,
 "daniel@yesql.se" <daniel@yesql.se>,
        "pgsql-hackers@postgresql.org" <pgsql-hackers@postgresql.org>,
        "michael@paquier.xyz" <michael@paquier.xyz>
Subject: Re: Preventing abort() and exit() calls in libpq
In-reply-to: <9d35a4ac-2c75-cb44-95ab-61d69deb072e@enterprisedb.com>
References: <3128896.1624742969@sss.pgh.pa.us>
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 <622907.1625084114@sss.pgh.pa.us> <630837.1625092151@sss.pgh.pa.us>
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 <9d35a4ac-2c75-cb44-95ab-61d69deb072e@enterprisedb.com>
Comments: In-reply-to Peter Eisentraut <peter.eisentraut@enterprisedb.com>
	message dated "Thu, 01 Jul 2021 20:05:59 +0200"
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Date: Thu, 01 Jul 2021 14:14:24 -0400
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Peter Eisentraut <peter.eisentraut@enterprisedb.com> writes:
> On 01.07.21 00:41, Jacob Champion wrote:
>> Spitballing -- if you don't like the stamp file, you could add the
>> check to the end of the $(shlib) rule, surrounded by an ifeq check.
>> Then .DELETE_ON_ERROR should take care of the rest, I think.

> Somewhere in the $(shlib) rule would seem most appropriate.  But I don't 
> understand the rest: What ifeq, and why .DELETE_ON_ERROR?

The variant of this I'd been thinking of was

 $(shlib): $(OBJS) | $(SHLIB_PREREQS)
 	$(LINK.shared) -o $@ $(OBJS) $(LDFLAGS) $(LDFLAGS_SL) $(SHLIB_LINK)
+ifneq (,$(SHLIB_EXTRA_ACTION))
+	$(SHLIB_EXTRA_ACTION)
+endif

(and similarly in several other places); then libpq's Makefile
could set SHLIB_EXTRA_ACTION to the desired thing.

The problem then is, what happens when the extra action fails?
Without .DELETE_ON_ERROR, the shlib is still there and the next
make run will think everything's good.

			regards, tom lane