I want to share status of my cross compiler packages work with all of you.
Some time ago I did a split of them into two:
- armel-cross-toolchain-base (1.36 now)
- armel-cross-toolchain (1.29 now)
Where first one provides binutils, linux headers, libc6 and libgcc
packages. Second provides final gcc.
Today I got a-c-t-base to a moment when it builds fine on PPA [1]. 1.36 got
sent for rebuild to fix missing gcc-4.5-arm-linux-gnueabi-base package. When
it will build then a-c-toolchain package will get uploaded for build.
Result will deprecate my current repository at people.canonical.com [2]
because PPA gives signed repository.
On Monday I will probably have to update both components because there was
gcc-4.4 upload so probably gcc-4.5 will follow (so I will be able to drop one
patch).
Additionally I made 'gcc-defaults-armel-cross' package (available in [1])
which makes installing of cross compilers a bit easier (no need to worry which
version to install - just "apt-get install gcc-arm-linux-gnueabi" is enough).
Selection of cross gcc version is done in other way then native one. Native is
using "gcc" package which contains /usr/bin/gcc as symlink to /usr/bin/gcc-4.4
file. Cross gcc uses "update-alternatives" to setup /usr/bin/arm-linux-
gnueabi-gcc file. I want to fix it in 11.04 so cross gcc will use same method
as native one.
1. https://edge.launchpad.net/~hrw/+archive/arm-cross-compiler
2. http://people.canonical.com/~hrw/ubuntu-maverick-armel-cross-compilers/
Regards,
--
JID: hrw(a)jabber.org
Website: http://marcin.juszkiewicz.com.pl/
LinkedIn: http://www.linkedin.com/in/marcinjuszkiewicz
Michael,
a quick update to our discussion today: actually, GDB 7.2 has already been
released earlier today:
http://sourceware.org/ml/gdb-announce/2010/msg00003.html
Mit freundlichen Gruessen / Best Regards
Ulrich Weigand
--
Dr. Ulrich Weigand | Phone: +49-7031/16-3727
STSM, GNU compiler and toolchain for Linux on System z and Cell/B.E.
IBM Deutschland Research & Development GmbH
Vorsitzender des Aufsichtsrats: Martin Jetter | Geschäftsführung: Dirk
Wittkopp
Sitz der Gesellschaft: Böblingen | Registergericht: Amtsgericht
Stuttgart, HRB 243294
Hi Alexander. I've looked into the problem and the linker error is
caused by a mix of stack protector options between libgcc and the C
library.
GCC includes a feature called the stack smashing protector which
detects writing past the end of a stack based object. It's quite nice
as it gives decent protection against buffer overruns which are the
most common type of security vulnerability.
The implementation is straight forward: when compiled with
-fstack-protector, any function with a stack-based character array
will have extra stack checking code inserted into the prologue and
epilogue. The prologue allocates a canary value at the top of stack
and fills it in with the value of '__stack_chk_guard' provided by
libssp. The epilogue checks this value and calls `__stack_chk_fail`
if it has been changed. The stack protector can interfere with some
code and isn't applicable in others.
The problem here is caused by a stack up of things:
* glibc knows about -fstack-protector and turns it on and off for
different functions and libraries
* gcc knows about -fstack-protector and includes libssp if required
* glibc knows about libgcc and statically links against it to ensure
availability
* Meego seems to turn on -fstack-protector by default (as does Ubuntu)
This results in the libgcc function '_gcc_Unwind_Backtrace' being
built with the stack protector and the glibc library 'libanl' without.
At static link time GCC sees that the stack protector is off and
skips linking against libssp, causing the missing symbol error.
The solution is to add -fno-stack-protector to the libgcc build
options and rebuild the compiler. I've heard (but can't track down
the link) that the ARM libgcc unwind functions must be built this way
in any case.
See
http://svn.debian.org/wsvn/gcccvs/branches/sid/gcc-4.5/debian/patches/gcc-d…
for how Debian does this.
Hope that helps,
-- Michael
On Fri, Aug 27, 2010 at 9:06 PM, <Alexander.Kanevskiy(a)nokia.com> wrote:
> Hi Michael.
>
> I've created for you account in MeeGo OBS (build system that we use in MeeGo
> is OpenSuSE build system)
>
> login: michaelh
> password: wog-feg-da
> Web client url: https://build.meego.com
> API url: https://api.meego.com
>
> The build log that had problem with glibc 2.12 + gcc 4.5 you can find here:
>
> https://build.meego.com/package/live_build_log?arch=armv7el&package=glibc&pr
> oject=home%3Akad%3Abranches%3ATrunk%3ATesting&repository=standard
>
> Might be you have some idea what went wrong, as our toolchain people were
> not able to find why combination of latest gcc plus glibc 2.11.x works, but
> not gcc 4.5 + glibc 2.12.0 :(
>
> This log is from my home project inside OBS, where stuff is already a bit
> outdated. I'll ask Jan-Simon from Linux Fundation to point to right place
> where latest builds are present, so you can experiment with them.
>
> --
> Best regards, Alexander Kanevskiy.
>
>
>
Hi all,
I've just discovered that Ubuntu is not using the Linaro release
information in the --version string. This is not ideal when we get bug
reports as it makes it hard to understand what Linaro release to use to
reproduce the issue.
Therefore, I've created a new wiki page to track the mappings:
https://wiki.linaro.org/WorkingGroups/ToolChain/VersionMappings
For now this only applies to GCC, but no doubt other tools will follow.
Please help keep it up to date if you find a version is missing. I've
added it to the GCC release process wiki page, so hopefully it should
get looked at at least once a month.
Andrew
Hi there. We have a Toolchain WG has a Versatile Express board coming
our way. It's a quad-core Cortex-A9 with 1 GB of RAM, so quite decent
really.
Does anyone have a pressing need for it? If not then I'll take it and
make it available over SSH.
-- Michael
Please find the activity reports and minutes for Monday's meeting
below. The minutes are also available at:
https://wiki.linaro.org/WorkingGroups/ToolChain/Meetings/2010-08-23
Minutes from the Wednesday and Friday standup calls are at:
https://wiki.linaro.org/WorkingGroups/ToolChain/Meetings/2010-08-18https://wiki.linaro.org/WorkingGroups/ToolChain/Meetings/2010-08-20
-- Michael
Attendees
• Name Email IRC Nick
Andrew Stubbs andrew.stubbs(a)linaro.org ams
Chung-Lin Tang cltang(a)codesourcery.com cltang
Matthias Klose doko(a)canonical.com doko
Michael Hope michael.hope(a)linaro.org michaelh
Peter Maydell peter.maydell(a)linaro.org pm215
Richard Earnshaw richard.earnshaw(a)arm.com rearnshaw
Yao Qi yao.qi(a)linaro.org yao
Agenda
• Open tickets
□ 616141 Backport the sync_* primitive fixes
□ 590696 fix wrong use of objdump during cross build
□ 600277 Backport ARM Cortex A9 scheduling changes
□ 605059 Merge 4.4.5
• Upcoming release
□ GCC 4.4
□ GCC 4.5
□ GDB
□ Strings
• 4.6 backport approach
• Creating blueprints
• Connecting with other groups
Blueprint Assignee
Initial delivery of Linaro GCC 4.4 ams
Cross Compiler Packages hrw
Action Items from this Meeting
• ACTION: Chung-Lin to move the list of other backports out of the CSL wiki
and into Linaro
• ACTION: Michael to re-check with TSC that we can assign copyright but keep
ability to relicense
• ACTION: Yao to continue on GDB for a week then switch to investigation
• ACTION: Peter to check into the state and progress of valgrind for the
meeting on the 30th.
Action Items from Previous Meeting
Minutes
Tickets:
• Went through the open tickets in the agenda
• Andrew will backport the SMP changes, including the sync primitives
• Andrew will backport the A9 changes
□ Most of the changes should come through easily
□ There is a write after write hazard
□ Currently uses the new cost infrastructure
□ Backport the cost infrastructure if it will be used further in the
future
4.6 branch:
• Andrew suggested starting a 4.6 branch after the start of stage 3
□ Start landing patches early
□ When FSF 4.6.0 comes out, we will have a corresponding Linaro 4.6.0
• ACTION: Chung-Lin to move the list of other backports out of the CSL wiki
and into Linaro
String routines:
• Richard asked about the response
• Michael had replies from Roland McGrath (http://sourceware.org/ml/
libc-alpha/2010-08/msg00029.html) but not the wider gcc-sc
• All other architectures are LGPL and FSF assigned
• The current approach is to assign a particular version to glibc
• Could cause a small maintenance problem in the future
• Richard isn't sure that we can assign copyright of a particular version
• ACTION: Michael to re-check with TSC that we can assign copyright but keep
ability to relicense
4.6 backports:
• Talked about the approach for backporting 4.6 features
• Won't backport every single change as then Linaro 4.5 becomes FSF 4.6
• Backport correctness fixes as the problem is found
• Backport performance changes as they occur
• Discussed how upstream could be tracked
□ Notification of any CSL or ARM authered changes will come from them
□ All changes are supposed to go through gcc-patches
□ Andrew notes that gcc-cvs provides a filtered view of what actually
landed
□ At least monitor these lists and search for ARM|Thumb|NEON|XSCALE|
Cortex|Coretx|VFP|Snapdragon|OMAP
Michael noted that IBM are interested in the ARM compiler and plan to get
involved soon.
Michael has asked again for A9 hardware. No news yet.
Future:
• Would like to spend some time soon running invetigrations to spit out some
blueprints
• ACTION: Yao to continue on GDB for a week then switch to investigation
• Andrew noted that there is one more person to come from CSL
• Will ask that person to do investigation
• Richard is keen to see the blueprints to check against what ARM is doing
□ Michael asked for information about their planning process so that we
can line things up
Valgrind:
• Peter noted that the valgrind changes have been committed upstream
• ACTION: Peter to check into the state and progress of valgrind for the
meeting on the 30th.
Next meeting is a stand-up meeting on 2010-08-25 on the public code.
--- Andrew Stubbs
== GCC 4.5 ==
* Continued pushing 4.5 patches to Linaro. I have now caught up with
current development I think.
* Lots of discussion on the patch tracker. You'd think it was more
important than the compiler .... :(
== Upstream ==
* Did before and after tests of the Coretex-A5 scheduler against
upstream HEAD. All seemed well (or at least, no worse) so I've posted
the patch upstream. No word back yet ....
--- Chung-Lin Tang
== Hard-float ==
* Testing EEMBC softfp vs. hard-float calling convention performance numbers.
* The only conclusive result was that OAmark is 2%-3% faster,
presumably due to vector graphics-like code in that suite. May look
into other code (was suggested Cairo) to see if any gain in changing
to hard-float.
* Withdraw earlier comment on small improvements on Automark (was not
apparent after more experiment runs).
* Currently working to produce report files.
== Linaro GCC ==
* Looking at getting into GCC backport work this week.
--- Yao Qi
== Linaro GDB ==
* LP:615997 gdb.dwarf2/dw2-ref-missing-frame.exp failure
Patch is committed to gdb mainline.
* LP:615999 gdb.gdb/selftest.exp failure
Patch is committed to gdb mainline.
* LP:615995 gdb.base/watch-vfork.exp : Watchpoint triggers after
vfork (sw) (timeout)
With Pedro's help, got to know the failure of this case on arm and
x86 are different. Created a patch as Ulrich suggested, and it works
on 2.6.32, while fails in a different way on 2.6.35. Failure is
caused by debuggee process is killed by a SIGTRAP. Still no clue why
that can happen.
== Linaro GCC ==
* My patch to PR45094 is approved, and checked in to mainline.
== This Week ==
* Fix LP:615995 and other linaro gdb bugs.
--- Ulrich Weigand
== GCC ==
* Collected and wrote up suggestions for future GCC work
== GDB ==
* Opened Launchpad bugs for known GDB problems and testsuite failures
* Investigated bug #620595 (gdb.threads/threxit-hop-specific.exp failure)
* Fixed bug #615998 (gdb.gdb/observer.exp failures) in mainline and 7.2
* Worked on upstream fix for #620595 (gdb.threads/threxit-hop-specific.exp
failure)
* Analyzed bug #620611 (Unable to backtrace out of vector page 0xffff0000)
== Infrastructure ==
* Continued working with our order&control team to acquire IGEPv2 boards
--- Peter Maydell
RAG:
Red: None
Amber: ARM legal OK for qemu contributions still pending
Green: we have approval for laptops for linaro secondees
Milestones:
| Planned | Estimate | Actual |
finish virtio-system | 2010-08-27 | 2010-08-27 | |
Progress:
virtio-system:
- got my versatile kernel/qemu running with virtio disk and network
versus non-virtio
- ran some basic benchmarking (bonnie++ for disk, tbench for net).
Disk is faster with virtio, but strangely networking is not!
- tried an upstream qemu too -- net virtio still slower
- built a realview kernel in preparation for testing Arnd's
PCI patches on hardware
qemu-focused-kernel:
- some research into which ARM dev boards support PCI in
hardware, kernel and qemu, to try to find a good choice for
basing a qemu-focused kernel on
merge-other-branches:
- started compiling list of qemu branches for possible consolidation
Issues: the intersection of (recent ARM hardware) (PCI support)
and (supported in qemu) looks suspiciously like the empty set.
Plans:
virtio-system:
- borrow some versatile or realview hardware and test Arnd
Bergmann's PCI patches
- make a start on writing up the config/benchmark results
qemu-focused-kernel:
- flesh out this blueprint
valgrind:
- try to build an ARM valgrind from upstream's thumb branch
Absences:
Friday 5 November and 20 other days in this calendar year
...are available here:
https://wiki.linaro.org/WorkingGroups/ToolChain/Meetings/2010-08-18
I'm going to stop sending out emails about the stand up minutes and
include links the weekly minutes instead.
Trick of the day:
w3m -dump https://wiki.linaro.org/WorkingGroups/ToolChain/Meetings/2010-08-18
| xclip -selection clipboard
...dumps a web page straight into your clipboard for pasting into an
email client.
-- Michael
Attendees
• Name Email IRC Nick
Andrew Stubbs andrew.stubbs(a)linaro.org ams
Yao Qi yao.qi(a)linaro.org yao
Ulrich Weigand ulrich.weigand(a)linaro.org uweigand
Peter Maydell peter.maydell(a)linaro.org pm215
Julian Brown julian(a)codesourcery.com jbrown
Loïc Minier loic.minier(a)linaro.org lool
Michael Hope michael.hope(a)linaro.org michaelh
Chung-Lin Tang cltang(a)codesourcery.com cltang
Agenda
• Standup meeting
Blueprint Assignee
Initial delivery of Linaro GCC 4.4 ams
Cross Compiler Packages hrw
Action Items from this Meeting
Action Items from Previous Meeting
• DONE: Michael to think about synchronising Linaro releases with upstream
• DONE: Michael to organise a call with Matthias, Loic to continue the topic
• DONE: Michael to write up and email patch tracker mechanics for review
• DONE: Ulrich to add his time away to the Linaro calendar
• ACTION: Michael and Ulrich to add GDB new features as blueprints to
Launchpad
• ACTION: Andrew to look into frequent runs of CSL benchmarks
• ACTION: Michael to make sure Linaro has a FSF copyright assignment
agreement
Minutes
• Michael
□ Continuing on patch tracking
□ Continuing investigating string routines
□ Julican noted that using NEON adds power usage and adds a context
switch cost
• Andrew
□ Has a few patches left to go
□ The ones left are a bit curlier
□ Reviewing the upstream state of the current patches
□ Will be sending the Cortex-A5 work upstream
• Yao
□ is continuing with the GDB bug fixes
□ Most are caused by the testsuite
□ Michael noted that we want to make any work we do available early. If
landing on trunk, either backport to 7.2 or note for later pulling into
our branch
• Ulrich
□ Working on bugs such as:
☆ Tracking thumb bit on a long jump
☆ Tracing in the kernel stubs
□ Is currently working upstream
□ Mentioned the ICACHE flush problem seen on Michael's board
☆ ACTION: Michael will try to upgrade the kernel from Angstrom 2.6.32
to a Linaro kernel
• Peter
□ Continues on virtio and QEMU
□ Network benchmark currently shows virtio performing worse than emulated
□ Looking upstream to see if this problem exists
□ Still waiting on approval to release work. Richard will take care of
next week
• Chung-Lin
□ Starting on hard vs soft FP performance tests
□ Testing on a i.MX51 board
□ Michael wants Chung-Lin to finish up on libffi soon
• Julian
□ Working on a vector conditions patch
□ Currently seeing a segfault in compiled applications
□ ACTION: Michael will re-try the build failures that Julian saw by the
end of this week
Next meeting is a stand-up meeting on 2010-08-20 on the public code.
The patch tracking conversation has got a little out-of-hand, and I know
I've misunderstood some of the features Michael has been proposing, and
I suspect vice versa.
So, here's my attempt to compare and contrast the various advantages,
disadvantages, and differences of the ideas so far, by means of use cases.
Looking at this, I think we can probably come up with a solution that
uses the good bits from each (maybe method 1 with the milestone/status
policy from method 2, for example).
Please read the below, and let me know if I left anything out, or if I
misunderstood something.
Andrew
====
For the purposes of this document:
* Method 0 is my original patch tracker, here:
https://wiki.linaro.org/WorkingGroups/ToolChain/GCC4.5UpstreamPatches
* Method 1 is Michael's proposed patch tracker, here:
https://wiki.linaro.org/WorkingGroups/ToolChain/PatchTracking#Method%201
and here: http://ex.seabright.co.nz/helpers/patchtrack
* Method 2 is my proposed system, here:
https://wiki.linaro.org/WorkingGroups/ToolChain/PatchTracking#Method%202
---------------------------------------------------------
1. What does a user have to do to get a patch tracked?
Method 0:
Nothing. New rows are added to the wiki page regularly by a script and
cron-job.
Method 1:
Nothing. The tracking report is updated regularly.
Method 2:
Nothing. New tickets are created automatically, regularly.
------------------------------------------------------------
2. How to find tracking information for a revision?
Method 0:
Search the wiki page for the revision number.
Method 1:
Goto the report page, click through to all the various associated
tickets, if any.
Method 2:
Go to launchpad, and search for "r123456", or select it from the list in
the relevant gcc-linaro-tracking milestone.
------------------------------------------------------------
3. How to find tracking information for a bug fix?
Method 0:
Search the wiki page for the bug number - hopefully somebody has posted
a link. Alternatively, the first line of the commit message will be
present. If that doesn't work, then find the revision number by other
means (bzr).
Method 1:
Go to the bug ticket - it should be there, or a link to another bug that
has it. Alternatively, go to the tracker report page, and search for the
commit message. If that fails try to identify the revision number by
other means (bzr)
Method 2:
Go to the bug ticket - if the bug was committed with --fixes, there will
be a link to the tracking ticket. Alternatively, search
gcc-linaro-tracking to find the commit message. If that fails try to
identify the revision number by other means (bzr)
----------------------------------------------------------
4. How to add new tracking information?
Method 0:
Edit the wiki page.
Method 1:
Add the new information to one or all of the associated bugs, if any. If
there are no existing tickets, create a new ticket (using the link on
the tracker report) and put the information there.
Method 2:
Add the information to the ticket.
-----------------------------------------------------------
5. How to indicate that the bug is upstream?
Method 0:
Edit the wiki page, set the bgcolor to green.
Method 1:
Assign all the bug tickets to a gcc-linaro-tracking milestone.
Method 2:
Mark the bug "Fix committed". Ensure that the ticket has the correct
milestone.
------------------------------------------------------------
6. How to list all patches that need to go upstream?
Method 0:
View the wiki page - the patches are highlighted in red and yellow.
Method 1:
View the tracker report - the patches are highlighted in red, yellow,
and orange.
(Note that launchpad will only list the patches that already had a
ticket attached, or else somebody has create one. This will usually only
include patches where somebody had something to say about it.)
Method 2:
All open bugs in gcc-linaro-tracking.
-------------------------------------------------------------
7. How to list all patches that need forwarding on rebase from 4.5 to 4.6?
Method 0:
Any patches marked in red or yellow on the wiki page need forwarding.
Any patches marked in green with an upstream landing number of 4.7 or
higher also need forwarding. (This information is not yet encoded in the
page, but it's a wiki, so flexibility is not a problem.)
Any patches in grey also need considering. Some are uninteresting
version bumps and such. Some are patches we plan to carry forever.
Probably a new colour could be used to make this clearer - it's a wiki.
Method 1:
Any patches in the report not yet upstream need forwarding. Any patches
in launchpad against the 4.7 milestone (or higher) also need forwarding.
Any patches in the "never" milestone also need considering. Some might
be ancient patches we used to carry in 4.4, but have since been dropped.
Some will be patches we intend to carry.
Method 2:
All patches against the 4.7 milestone, both open and closed (modify the
launchpad search criteria) need forwarding. All patches in the
"series:never,milestone:4.5" milestone in the "won't fix" state need
forwarding.
(Patches we don't intend to carry forward will be "closed", and patches
from 4.4 won't be in "series:never,milestone:4.5", so we never have to
worry about those.)
------------------------------------------------------------------
8. How to we track what patches have been forwarded on rebase already?
Method 0:
It's a wiki, add a column.
Method 1:
Committing the patch on a new branch will (with --fixes) will cause
launchpad to list the commit on the bug page. There's no way to query
this though.
Method 2:
Committing the patch on a new branch will give a "new" patch to track.
The trackerbot will create a new ticket for this revision. The old
ticket will be marked as a "duplicate" of the new one (manually, or
automatically). The new bugs will have "4.6/r123456" in the subject
line, so can be easily be differentiated.
-----------------------------------------------------------------
9. What else needs doing on a rebase?
Method 0:
Create a new page with a new table. Forward the information from the old
table manually, by editing the wiki.
Method 1:
Create a new tracker report.
Method 2:
Set up the trackerbot on the new branch.
------------------------------------------------------------------
10. What prompts users to use the system?
Method 0:
Nothing. (Management nagging.)
Method 1:
Nothing mentioned so far.
Method 2:
The bug is always assigned to somebody. They'll be notified by email,
and it will show up on their launchpad pages.
------------------------------------------------------------------
11. What happens when a bug produces multiple patches?
Method 0:
Multiple lines in the table, initially. But, it's a wiki, so they can be
edited, moved around, and coalesced as required.
Method 1:
The same bug has to track multiple patches.
????? How does that work with the 'affects gcc-linaro-tracking' lines?
Method 2:
One ticket per commit. Each is tracked separately, but the user is free
to mark each ticket as a duplicate of the other, and/or move the data
from one ticket to another.
------------------------------------------------------------------
12. What happens when one commit fixes multiple bugs?
Method 0:
Nothing special.
Method 1:
Multiple bugs will track the same submission process. Either the user
must post all the data to all the bugs, or one bug must get (manually)
appointed the master bug, and the others have links posted.
Method 2:
One ticket will be created to track the patch. The ticket will contain
links to all the bugs, and each bug will contain a back-link. This is
very little different to the normal case.
I've fleshed out a potential way of tracking patches at:
https://wiki.linaro.org/WorkingGroups/ToolChain/PatchTracking#Method%201
It's not too bad if you're a developer. The extra steps are:
* Create a ticket
* Mark that ticket as affecting upstream
* Change the status as the patch evolves
* Mark where the patch lands when finished
This is all done through Launchpad's existing interface.
Thoughts?
-- Michael
Sorry about these. Hopefully I'm done.
On Thu, Aug 19, 2010 at 2:28 PM, Michael Hope <620229(a)bugs.launchpad.net> wrote:
> Public bug reported:
>
> Related: lp:gcc-linaro/4.5,revno=99360
>
> Code hoisting improvements
>
> Merged from SourceryG++
>
> (Backport from FSF)
>
> ** Affects: gcc-linaro
> Importance: Undecided
> Status: New
>
> ** Affects: gcc-linaro/4.5
> Importance: Undecided
> Status: New
>
>
> ** Tags: revision
>
> --
> [4.5:r99360] Code hoisting improvements
> https://bugs.launchpad.net/bugs/620229
> You received this bug notification because you are a direct subscriber
> of the bug.
>
> Status in Linaro GCC: New
> Status in Linaro GCC 4.5 series: New
>
> Bug description:
> Related: lp:gcc-linaro/4.5,revno=99360
>
> Code hoisting improvements
>
> Merged from SourceryG++
>
> (Backport from FSF)
>
>
> To unsubscribe from this bug, go to:
> https://bugs.launchpad.net/gcc-linaro/+bug/620229/+subscribe
>
