430112 - <nsAutoLock.cpp>: 2 "warning: unused variable status"

Status: RESOLVED FIXED

(Core :: XPCOM, defect)

Description

[Serge Gautherie (:sgautherie)]

"Linux cb-sea-linux-tbox Depend Nightly on 2008/04/21 09:16:00"
{{
/xpcom/glue/nsAutoLock.cpp: In member function ‘void nsAutoMonitor::Exit()’:
/xpcom/glue/nsAutoLock.cpp:451: warning: unused variable ‘status’
/xpcom/glue/nsAutoLock.cpp: In member function ‘void nsAutoCMonitor::Exit()’:
/xpcom/glue/nsAutoLock.cpp:478: warning: unused variable ‘status’
}}

Comment 1

[Serge Gautherie (:sgautherie)]

Attachment: (Av1) <nsAutoLock.cpp>

Comment 2

[:Gavin Sharp [email: [e-mail]]]

That's the wrong bsmedberg to request review from, you want ":bs" or "[e-mail]".

Comment 3

[Benjamin Smedberg]

Comment on attachment 316852 [details] [diff] [review]
(Av1) <nsAutoLock.cpp>

This is ugly. Does GCC report the same warning if you do:

  PRStatus status;
  status = PR_ExitMonitor(mMonitor);
  NS_ASSERTION(...);

Comment 4

[Serge Gautherie (:sgautherie)]

http://tinderbox.mozilla.org/showlog.cgi?log=Firefox/1245837743.1245841544.9931.gz&fulltext=1
Linux mozilla-central nightly on 2009/06/24 03:02:23
http://tinderbox.mozilla.org/showlog.cgi?log=Firefox/1245839844.1245844096.16862.gz&fulltext=1
OS X 10.5.2 mozilla-central nightly on 2009/06/24 03:37:24
(Windows: no warnings.)

I'll _Try_ comment 3...

Comment 5

[Serge Gautherie (:sgautherie)]

Attachment: (Bv1-Try) 2 other ways to rewrite [Checkin: See comment 8]

"sgautherie.bz#free.fr / try-ca1dd5a900a":
both ways suppress the warning :-)

I think the latter should give smaller/faster compiled code.
(The former would need a comment to explain why 2 lines.)
I'll check it in with the way you want...

Comment 6

[Serge Gautherie (:sgautherie)]

Comment on attachment 385005 [details] [diff] [review]
(Bv1-Try) 2 other ways to rewrite
[Checkin: See comment 8]


Benjamin, thanks for the review, but which way do you want for checkin?

Comment 7

[Benjamin Smedberg]

Comment on attachment 385005 [details] [diff] [review]
(Bv1-Try) 2 other ways to rewrite
[Checkin: See comment 8]

Oh, I didn't realize you had two different options here! Use the first way... any good compiler will optimize away the unused local.

Comment 8

[Serge Gautherie (:sgautherie)]

Comment on attachment 385005 [details] [diff] [review]
(Bv1-Try) 2 other ways to rewrite
[Checkin: See comment 8]


http://hg.mozilla.org/mozilla-central/rev/232b3e116bbd
(Bv1) Split the init to 2 instructions