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	Fri, 21 Jun 2019 09:25:31 -0400
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: Re: using explicit_bzero
In-reply-to: <42d26bde-5d5b-c90d-87ae-6cab875f73be@2ndquadrant.com>
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Comments: In-reply-to Peter Eisentraut <peter.eisentraut@2ndquadrant.com>
	message dated "Fri, 21 Jun 2019 09:25:43 +0200"
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Date: Fri, 21 Jun 2019 09:25:31 -0400
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Peter Eisentraut <peter.eisentraut@2ndquadrant.com> writes:
> +#ifndef HAVE_EXPLICIT_BZERO
> +#define explicit_bzero(b, len) bzero(b, len)
> +#endif

This presumes that every platform has bzero, which is unsafe (POSIX
doesn't specify it) and is an assumption we kicked to the curb a dozen
years ago (067a5cdb3).  Please use memset() for the substitute instead.

Also, I'm a bit suspicious of using AC_CHECK_FUNCS for this; that
generally Doesn't Work for anything that's not a vanilla out-of-line
function.  Are we worried about people implementing this as a macro,
compiler built-in, etc?

			regards, tom lane