From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alvaro Herrera <alvherre@2ndquadrant.com>
cc: pgsql-hackers@lists.postgresql.org
Subject: Re: printf format selection vs. reality
In-reply-to: <8383.1527107335@sss.pgh.pa.us>
References: <20180523201046.4znqfw52bmr6o3gr@alvherre.pgsql>
 <8383.1527107335@sss.pgh.pa.us>
Comments: In-reply-to Tom Lane <tgl@sss.pgh.pa.us>
	message dated "Wed, 23 May 2018 16:28:55 -0400"
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Date: Wed, 23 May 2018 18:04:04 -0400
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Sigh, I'm an idiot.  I forgot that USE_REPL_SNPRINTF doesn't just
replace snprintf, it replaces the entire *printf family; see
port.h lines 137ff.  So actually we're OK as far as these %z and
argument-reordering concerns go.  Maybe the comments in configure
could use a bit of work though.

There's maybe also an argument for reverting b929614f5, because
actually that code did do something useful, ie allow us to work on
platforms without %ll.  But I'm inclined to leave that alone;
it's an extra configure test to detect a case that probably no longer
occurs in the wild.  Moreover, since %ll and %z are both C99-isms,
and the former had considerable currency even before C99 (evidence:
gaur/pademelon) it's pretty hard to credit that a platform's *printf
would fail the %ll test yet pass the %z test.  So I think we're
likely OK without it, even on dinosaur platforms.

			regards, tom lane