Bug 445301 - -fmerge-all-constants could be more effective
Summary: -fmerge-all-constants could be more effective
Keywords:
Status: CLOSED WONTFIX
Alias: None
Product: Fedora
Classification: Fedora
Component: gcc
Version: 14
Hardware: All
OS: Linux
low
low
Target Milestone: ---
Assignee: Jakub Jelinek
QA Contact: Fedora Extras Quality Assurance
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2008-05-06 00:55 UTC by Ulrich Drepper
Modified: 2011-12-28 05:02 UTC (History)
1 user (show)

Fixed In Version:
Doc Type: Bug Fix
Doc Text:
Clone Of:
Environment:
Last Closed: 2011-12-28 05:02:53 UTC
Type: ---
Embargoed:


Attachments (Terms of Use)

Description Ulrich Drepper 2008-05-06 00:55:46 UTC
Description of problem:
Given this code

struct f { int a,b; };
const struct f f1[] = { { 1, 2 }, { 3, 4 } };
const struct f f2[] = { { 1, 2 }, { 3, 4 } };
const struct f f3[] = { { 1, 2 }, { 3, 4 } };

gcc today does not perform any kind of merging when -fmerge-all-contants is
used.  Possibilities:

- intra-CU merging should happen here in any case when the option is given

- inter-CU merging can also be tried by moving the data in an appropriately
  named section (until gas/bfd do not depend on names anymore) which has the
  SHF_MERGE flag set


Version-Release number of selected component (if applicable):
gcc-4.3.0-8
and all prio versions

How reproducible:
always

Steps to Reproduce:
1.compile code above with -fmerge-all-constants
2.
3.
  
Actual results:
no merging, three separate variables allocated

Expected results:
intra CU merging and using a section which allows inter CU merging

Additional info:

Comment 1 Bug Zapper 2008-05-14 10:41:57 UTC
Changing version to '9' as part of upcoming Fedora 9 GA.
More information and reason for this action is here:
http://fedoraproject.org/wiki/BugZappers/HouseKeeping

Comment 2 Bug Zapper 2009-06-10 00:38:15 UTC
This message is a reminder that Fedora 9 is nearing its end of life.
Approximately 30 (thirty) days from now Fedora will stop maintaining
and issuing updates for Fedora 9.  It is Fedora's policy to close all
bug reports from releases that are no longer maintained.  At that time
this bug will be closed as WONTFIX if it remains open with a Fedora 
'version' of '9'.

Package Maintainer: If you wish for this bug to remain open because you
plan to fix it in a currently maintained version, simply change the 'version' 
to a later Fedora version prior to Fedora 9's end of life.

Bug Reporter: Thank you for reporting this issue and we are sorry that 
we may not be able to fix it before Fedora 9 is end of life.  If you 
would still like to see this bug fixed and are able to reproduce it 
against a later version of Fedora please change the 'version' of this 
bug to the applicable version.  If you are unable to change the version, 
please add a comment here and someone will do it for you.

Although we aim to fix as many bugs as possible during every release's 
lifetime, sometimes those efforts are overtaken by events.  Often a 
more recent Fedora release includes newer upstream software that fixes 
bugs or makes them obsolete.

The process we are following is described here: 
http://fedoraproject.org/wiki/BugZappers/HouseKeeping

Comment 3 Bug Zapper 2009-11-16 08:05:25 UTC
This bug appears to have been reported against 'rawhide' during the Fedora 12 development cycle.
Changing version to '12'.

More information and reason for this action is here:
http://fedoraproject.org/wiki/BugZappers/HouseKeeping

Comment 4 Bug Zapper 2010-11-04 11:55:31 UTC
This message is a reminder that Fedora 12 is nearing its end of life.
Approximately 30 (thirty) days from now Fedora will stop maintaining
and issuing updates for Fedora 12.  It is Fedora's policy to close all
bug reports from releases that are no longer maintained.  At that time
this bug will be closed as WONTFIX if it remains open with a Fedora 
'version' of '12'.

Package Maintainer: If you wish for this bug to remain open because you
plan to fix it in a currently maintained version, simply change the 'version' 
to a later Fedora version prior to Fedora 12's end of life.

Bug Reporter: Thank you for reporting this issue and we are sorry that 
we may not be able to fix it before Fedora 12 is end of life.  If you 
would still like to see this bug fixed and are able to reproduce it 
against a later version of Fedora please change the 'version' of this 
bug to the applicable version.  If you are unable to change the version, 
please add a comment here and someone will do it for you.

Although we aim to fix as many bugs as possible during every release's 
lifetime, sometimes those efforts are overtaken by events.  Often a 
more recent Fedora release includes newer upstream software that fixes 
bugs or makes them obsolete.

The process we are following is described here: 
http://fedoraproject.org/wiki/BugZappers/HouseKeeping

Comment 5 Bug Zapper 2010-12-05 07:10:59 UTC
Fedora 12 changed to end-of-life (EOL) status on 2010-12-02. Fedora 12 is 
no longer maintained, which means that it will not receive any further 
security or bug fix updates. As a result we are closing this bug.

If you can reproduce this bug against a currently maintained version of 
Fedora please feel free to reopen this bug against that version.

Thank you for reporting this bug and we are sorry it could not be fixed.

Comment 6 Ulrich Drepper 2010-12-05 11:53:08 UTC
Still not changed in F14 and still valid.

Comment 7 Aravind vijayan 2011-12-28 05:02:53 UTC
    Thank you for your bug report. 

    We are sorry, but the Fedora Project is no longer releasing bug fixes or any other updates for this version of Fedora. This bug will be set to CLOSED:WONTFIX to reflect this, but please reopen it if the problem persists after upgrading to the latest version of Fedora, which is available from: 

    http://fedoraproject.org/get-fedora 



-- 
Fedora Bugzappers volunteer triage team
https://fedoraproject.org/wiki/BugZappers


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