Re: do {} while (0) nitpick - Mailing list pgsql-hackers

From Bruce Momjian
Subject Re: do {} while (0) nitpick
Date
Msg-id 20200501015236.GB31271@momjian.us
Whole thread Raw
In response to Re: do {} while (0) nitpick  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: do {} while (0) nitpick
Re: do {} while (0) nitpick
List pgsql-hackers
On Thu, Apr 30, 2020 at 09:51:10PM -0400, Tom Lane wrote:
> John Naylor <john.naylor@2ndquadrant.com> writes:
> > As I understand it, the point of having "do {} while (0)" in a
> > multi-statement macro is to turn it into a simple statement.
> 
> Right.
> 
> > As such,
> > ending with a semicolon in both the macro definition and the
> > invocation will turn it back into multiple statements, creating
> > confusion if someone were to invoke the macro in an "if" statement.
> 
> Yeah.  I'd call these actual bugs, and perhaps even back-patch worthy.

Agreed.  Those semicolons could easily create bugs.

-- 
  Bruce Momjian  <bruce@momjian.us>        https://momjian.us
  EnterpriseDB                             https://enterprisedb.com

+ As you are, so once was I.  As I am, so you will be. +
+                      Ancient Roman grave inscription +



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