Date: Wed, 23 Mar 2022 18:06:36 -0700
To: Thomas Munro <thomas.munro@gmail.com>
Cc: Peter Eisentraut <peter.eisentraut@enterprisedb.com>,
	David Christensen <david.christensen@crunchydata.com>,
	Bharath Rupireddy <bharath.rupireddyforpostgres@gmail.com>,
	PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: [PATCH] add relation and block-level filtering to pg_waldump
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[IFrom: Andres Freund <andres@anarazel.de>
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On 2022-03-24 11:54:15 +1300, Thomas Munro wrote:
> Erm, is that really OK?  C says "Each enumerated type shall be
> compatible with char, a signed integer type, or an
> unsigned integer type. The choice of type is implementation-defined,
> but shall be capable of representing the values of all the members of
> the enumeration."  It could even legally vary from enum to enum,
> though in practice most compilers probably just use ints all the time
> unless you use weird pragma pack incantation.  Therefore I think you
> need an intermediate variable with the size and signedness matching the
> format string, if you're going to scanf directly into it, which
> David's V6 did.

/me yearns for the perfectly reasonable C++ 11 feature of defining the base
type for enums (enum name : basetype { }). One of those features C should have
adopted long ago. Not that we could use it yet, given we insist that C
standards have reached at least european drinking age before relying on them.