Article View: gnu.gcc.bug
Article #2813Re: gcc warning: empty body in else-statement
From: Arthur David Olson
Date: Tue, 09 Jan 1990 01:23
Date: Tue, 09 Jan 1990 01:23
31 lines
1423 bytes
1423 bytes
> If I compile with -Wall, I get warnings about else statements with
> empty bodies, e.g.
>
> if (expr)
> f();
> else ;
>
> ...These warnings don't seem very useful to me; am I missing something?
> Is there a common error that will be caught by the warning?
The "common" error caught by the code generating the above message is...
if (expression);
statement;
...where the extra semicolon at the end of the first line results in
"statement" being executed unconditionally. The "else" case is designed to
guard against the less-common...
if (expression);
statement;
else; if (expression2)
statement2;
else statement3;
On the system here at least, you can eliminate the warning by having the
macro generate code in the form...
if (expr)
f();
else {}
--
1972: Canada has no Saturn V equivalent
1990: Canada has no Saturn V equivalent
Arthur David Olson ado@alw.nih.gov ADO is a trademark of Ampex.
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Path: arc1-ca.pugleaf.net!utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!aplcen!uakari.primate.wisc.edu!brutus.cs.uiuc.edu!psuvax1!ukma!dftsrv!mimsy!cvl!elsie!ado From: ado@elsie.UUCP (Arthur David Olson) Newsgroups: gnu.gcc.bug Subject: Re: gcc warning: empty body in else-statement Message-ID: <9237@elsie.UUCP> Date: 9 Jan 90 01:23:40 GMT References: <9001082242.AA00768@jan.ultra.nyu.edu> Distribution: gnu Organization: NIH-LEC, Bethesda, MD Lines: 31