230001 - <ptio.c>: Fix 2* ['start' might be used uninitialized in this function] from 'Blamed Build Warnings; Linux brad Clobber'; and code cleanup.

Status: RESOLVED WORKSFORME

(NSPR :: NSPR, defect)

Description

[Serge Gautherie (:sgautherie)]

The two ("bogus") warnings are:

{ (unblamed)
3.	nsprpub/pr/src/pthreads/ptio.c:3748 (See build log excerpt)
	`start' might be used uninitialized in this function

3746 

4.	nsprpub/pr/src/pthreads/ptio.c:4816 (See build log excerpt)
	`start' might be used uninitialized in this function

4814 
}

The code is right, but the compiler does not track the |if| conditions.

Comment 1

[Serge Gautherie (:sgautherie)]

Attachment: (Av1) <ptio.c> warning fix

Comment 2

[Serge Gautherie (:sgautherie)]

Comment on attachment 138360 [details] [diff] [review]
(Av1) <ptio.c> warning fix


'r=?': (see comment 0)
I have no compiler: Could you compile/test/review it ? Thanks.

Comment 3

[Serge Gautherie (:sgautherie)]

Attachment: (Bv1) <ptio.c> code cleanup

Comment 4

[Serge Gautherie (:sgautherie)]

Comment on attachment 138364 [details] [diff] [review]
(Bv1) <ptio.c> code cleanup


I have no compiler: Could you compile/test/review it ? Thanks.

Comment 5

[Serge Gautherie (:sgautherie)]

Attachment: (Av1a) ptio.c: warning fix and little code cleanup

Uncompiled, as this directory is not present in my Windows objdir.

I'll realign the code in a follow-up patch.

***

Bug still there:
http://office.smedbergs.us:8080/search?user=&path=%25pthreads%25&msg=%25uninitialized%25&id=1280
# nsprpub/pr/src/pthreads/ptio.c:3762 - 'start' may be used uninitialized in this function
# nsprpub/pr/src/pthreads/ptio.c:4916 - 'start' may be used uninitialized in this function

Comment 6

[Serge Gautherie (:sgautherie)]

(In reply to comment #5)
> Uncompiled, as this directory is not present in my Windows objdir.

Tryserver is green with this as 'try-a6cb5e72ff8'.

Yet there are additional warnings:
{
Linux:
/builds/buildbot/sendchange-slave/sendchange-linux-hg/mozilla/nsprpub/pr/src/pthreads/ptio.c: In function ‘pt_writev_cont’:
/builds/buildbot/sendchange-slave/sendchange-linux-hg/mozilla/nsprpub/pr/src/pthreads/ptio.c:903: warning: dereferencing type-punned pointer will break strict-aliasing rules

Mac PPC:
/builds/slave/sendchange-mac-hg/mozilla/nsprpub/pr/src/pthreads/ptio.c: In function '_PR_InitIO':
/builds/slave/sendchange-mac-hg/mozilla/nsprpub/pr/src/pthreads/ptio.c:1174: warning: pointer targets in passing argument 5 of 'getsockopt' differ in signedness
/builds/slave/sendchange-mac-hg/mozilla/nsprpub/pr/src/pthreads/ptio.c: In function 'PR_Socket':
/builds/slave/sendchange-mac-hg/mozilla/nsprpub/pr/src/pthreads/ptio.c:3456: warning: unused variable 'tmp_domain'

Mac i386:
/builds/slave/sendchange-mac-hg/mozilla/nsprpub/pr/src/pthreads/ptio.c: In function '_PR_InitIO':
/builds/slave/sendchange-mac-hg/mozilla/nsprpub/pr/src/pthreads/ptio.c:1174: warning: pointer targets in passing argument 5 of 'getsockopt' differ in signedness
/builds/slave/sendchange-mac-hg/mozilla/nsprpub/pr/src/pthreads/ptio.c: In function 'PR_Socket':
/builds/slave/sendchange-mac-hg/mozilla/nsprpub/pr/src/pthreads/ptio.c:3456: warning: unused variable 'tmp_domain'
/builds/slave/sendchange-mac-hg/mozilla/nsprpub/pr/src/pthreads/ptio.c: In function 'pt_Available_f':
/builds/slave/sendchange-mac-hg/mozilla/nsprpub/pr/src/pthreads/ptio.c:1472: warning: 'end' may be used uninitialized in this function
/builds/slave/sendchange-mac-hg/mozilla/nsprpub/pr/src/pthreads/ptio.c: In function 'pt_Available64_f':
/builds/slave/sendchange-mac-hg/mozilla/nsprpub/pr/src/pthreads/ptio.c:1491: warning: 'end' may be used uninitialized in this function
}

Comment 7

[Nelson Bolyard (seldom reads bugmail)]

Comment on attachment 371851 [details] [diff] [review]
(Av1a) ptio.c: warning fix and little code cleanup

The following change moves executable code up, so that it 
precedes an automatic variable definition.  That's OK in c++
and in some versions of c, but some of the c compilers on 
platforms supported by NSPR do not allow it.  So, r- for that.

> static PRInt32 _pr_poll_with_poll(
>     PRPollDesc *pds, PRIntn npds, PRIntervalTime timeout)
> {
>+    if (pt_TestAbort())
>+        return -1;
>+
>+    if (0 == npds) {
>+        PR_Sleep(timeout);
>+        return 0;
>+    }
>+
>     PRInt32 ready = 0;

Comment 8

[Atul Aggarwal]

We don't have uninitialized variable in ptio.c file. We do have "variable xx set but not used" warning but that will be tracked by different bug.
Hence Closing this bug.