Horton

Re: taking stdbool.h into use

Michael Paquier <michael.paquier@gmail.com>

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From: Michael Paquier <michael.paquier@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Alvaro Herrera <alvherre@alvh.no-ip.org>, Peter Eisentraut <peter.eisentraut@2ndquadrant.com>, pgsql-hackers <pgsql-hackers@postgresql.org>, Thomas Munro <thomas.munro@enterprisedb.com>
Date: 2017-10-28T23:11:34Z
Lists: pgsql-hackers 
On Thu, Oct 26, 2017 at 5:41 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> While warnings for this would be lovely, I don't see how we can expect to
> get any.  This is perfectly correct C code no matter whether isprimary
> is C99 bool or is typedef'd to char ... you just end up with different
> values of isprimary, should the RHS produce something other than 1/0.
> The compiler has no way to know that assigning, say, 4 in the char
> variable case is not quite your intent.  Maybe you could hope for a
> warning if the bit value were far enough left to actually not fit into
> "char", but otherwise there's nothing wrong.

This reminded me of
https://www.postgresql.org/message-id/20160212144735.7zkg5527i3un3254%40alap3.anarazel.de
which has caused commit af4472bc when using stdbool.h for MSVC
2013/2015 builds. So I would really assume that there are places where
we could see warnings.
-- 
Michael

Commits

  1. Use stdbool.h if suitable

  2. Add configure tests for stdbool.h and sizeof bool

  3. Remove useless use of bit-masking macros

  4. Change various Gin*Is* macros to return 0/1.

  5. Fix several possibly non-portable gaffs in record_image_ops.