Horton

Re: do {} while (0) nitpick

Tom Lane <tgl@sss.pgh.pa.us>

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From: Tom Lane <tgl@sss.pgh.pa.us>
To: John Naylor <john.naylor@2ndquadrant.com>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2020-05-01T01:51:10Z
Lists: pgsql-hackers 
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.

			regards, tom lane

Commits

  1. Get rid of trailing semicolons in C macro definitions.