As you probably know I am working on bootstrapping cross compiler. Process is
described on https://wiki.linaro.org/CrossCompilers page.
Current status is: nearly done.
Done:
- Linux/stage1 - patch (LP:603087) waits approval from kernel team.
- GCC 4.5/stage[12] - patch (LP:603497) created
In progress:
- eglibc/stage1 builds but needs packaging work
Problems:
- gcc/stage3 (normal full build) fails on shlibs because I do not have
libc6-armel packages installed in system but dpkg-shlibdeps needs them
How to bootstrap cross compiler?
- apt-get source gcc-4.5 eglibc binutils linux-image-2.6.35-8-generic
- copy gcc-4.5 dir to gcc-stage1 gcc-stage2 gcc-stage3
- copy eglibc dir to eglibc-stage1 eglibc-stage2
- fetch and apply my patches from LP:603087 LP:603497 LP:603498
- create directory "sysroot/" and point WITH_SYSROOT and WITH_BUILD_SYSROOT
enviroment variables to it
- cd binutils* && TARGET=armel dpkg-buildpackage -b -uc -us
- cd sysroot && dpkg-deb -x ../binutils-arm*deb .
- export PATH=$PWD/sysroot/usr/bin:$PATH
- export LD_LIBRARY_PATH=$PWD/sysroot/usr/x86_64-linux*/usr/arm*/lib
- cd linux* && DEB_STAGE=stage1 dpkg-buildpackage -b -uc -us -aarmel
- cd sysroot && dpkg-deb -x ../linux-libc-dev*deb .
- cd gcc-stage1 && DEB_STAGE=stage1 dpkg-buildpackage -b -uc -us
- cd sysroot && dpkg-deb -x ../cpp*deb ../gcc*deb .
- cd eglibc-stage1 && DEB_STAGE=stage1 dpkg-buildpackage -b -uc -us -aarmel
As packaging is not yet done for that step manual copying of debian/tmp-libc/
contents to sysroot dir is needed.
- cd gcc-stage2 && DEB_STAGE=stage2 dpkg-buildpackage -b -uc -us
- cd sysroot && dpkg-deb -x ../cpp*deb ../gcc*deb .
- cd eglibc-stage2 && dpkg-buildpackage -b -uc -us -aarmel
- cd sysroot && dpkg-deb -x ../libc*deb .
- cd gcc-stage3 && dpkg-buildpackage -b -uc -us
Here dpkg-shlibdeps will complain so for that step manual copying of
debian/tmp/ contents to sysroot dir is needed.
sysroot dir will then contain working cross compiler - so far I used it to
compile hello.c and kernel for beagleboard
I did not tested yet building stage3 compiler with sysroot=/ like it should be
for installing it on other systems. But thats future.
Regards,
--
JID: hrw(a)jabber.org
Website: http://marcin.juszkiewicz.com.pl/
LinkedIn: http://www.linkedin.com/in/marcinjuszkiewicz
...are available at:
http://ex.seabright.co.nz/build/gcc-linaro-4.5+bzr99315/
I've also finished reference builds of FSF GCC 4.4.4, 4.5.0, and
4.5.1. According to the GCC testsuite, there are no regressions
between the Linaro and FSF branches and in some ways we're a bit
better:
On x86_64 for FSF 4.5.0 (-) vs linaro-4.5+bzr99315 (+):
=== gcc Summary ===
-# of expected passes 61211
+# of expected passes 61239
+# of unexpected successes 1
-# of expected failures 180
+# of expected failures 179
# of unsupported tests 825
On i686 FSF 4.5.0 vs linaro-4.5+bzr99315:
=== gcc Summary ===
-# of expected passes 62285
+# of expected passes 62309
# of unexpected failures 12
-# of unexpected successes 25
+# of unexpected successes 26
-# of expected failures 192
+# of expected failures 191
# of unsupported tests 533
g++, fortran, and objc are the same between builds.
And, strangely enough, ARM is still building.
-- Michael
Minutes from the Toolchain WG weekly meeting are available at:
https://wiki.linaro.org/WorkingGroups/ToolChain/Meetings/2010-08-02
A copy, along with activity reports, follow.
-- Michael
= Monday 2nd August 2010 =
== This month's meetings ==
<<MonthCalendar(WorkingGroups/ToolChain/Meetings,2010,08,,,,WorkingGroups/ToolChain/MeetingTemplate)>>
== Attendees ==
||<rowbgcolor="#333333" rowstyle="color: white; font-weight:
bold;"style="text-align: center;">Name ||<style="text-align:
center;">Email ||<style="text-align: center;">IRC Nick ||
|| Andrew Stubbs || andrew.stubbs(a)linaro.org || ams ||
|| Julian Brown || julian(a)codesourcery.com || jbrown ||
|| Michael Hope || michael.hope(a)linaro.org || michaelh ||
|| Richard Earnshaw || richard.earnshaw(a)arm.com || rearnshaw ||
|| Ulrich Weigand || ulrich.weigand(a)linaro.org || uweigand ||
|| Yao Qi || yao.qi(a)linaro.org || yao ||
== Agenda ==
* Review action items from last meeting
* New public call-in number: code 263 441 7169
* Hardware availability
* Next milestone
* Outstanding changes that could be merged
* GCC testsuite failures and what to do about them
* http://ex.seabright.co.nz/helpers/testlog/gcc-linaro-4.4-93543/logs/armv7l-…
||<rowbgcolor="#333333" rowstyle="color: white; font-weight:
bold;"style="text-align: center;">Blueprint ||<style="text-align:
center;">Assignee ||
|| [[https://blueprints.launchpad.net/gcc-linaro/+spec/initial-4.4|Initial
delivery of Linaro GCC 4.4]] || ams ||
|| [[https://blueprints.launchpad.net/ubuntu/+spec/arm-m-cross-compilers|Cross
Compiler Packages]] || hrw ||
== Action Items from this Meeting ==
* ACTION: Michael to organise and spread next Monday's call in number
* ACTION: Richard to ask the GCC developers on IRC what the status of 4.4.5 is
* ACTION: [[LP:500524]] Ulrich to backport to Linaro 4.4
* ACTION: Test failures: Michael to build FSF 4.4.4 as a baseline
* ACTION: Test failures: Michael to compare FSF and Linaro GCC failures
* ACTION: Test failures: All Linaro GCC failures to be ticketed
* ACTION: LTO check on ARM: Michael to reproduce
* ACTION: Ulrich to write up known GDB work
* ACTION: [[LP:598147]]: Michael to reproduce the test failures
* ACTION: [[LP:398403]]: Andrew to reproduce on his IGEP board (has more RAM)
* ACTION: Michael to make sure merge requests are present for work
that has been done
== Action Items from Previous Meeting ==
* ACTION: Michael to organise and spread next Monday's call in number
* DONE: Michael to re-check release dates and suggest something
* Set to the second Tuesday of each month. Lines up with other
Linaro releases quite well.
* DONE: Michael to rename the intermediate milestone
* Set to 2010.08-0. Created 2010.09-0 for the next.
* DONE: Loic to find the Chrome OS contact name for the records
* DONE: Ulrich to confirm PowerPC approach with Matthias
* Confirmed that reverting the PowerPC changes is OK
== Minutes ==
* Reviewed the action items from the previous meeting
* Reviewed the high-priority tickets
* Merging 4.4.5
* Michael is unhappy with merging for next weeks release unless
4.4.5 comes out in the next few days
* Richard went through the announcements. Last was for 4.4.4 on April 30.
* 4.4.5 is due around now
* Expect that the GCC team are focused on 4.5.1 instead
* ACTION: Richard to ask the GCC developers on IRC what the status
of 4.4.5 is
* [[LP:500524]]
* Ulrich has done upstream in 4.4.5
* A small change, unlikely to cause correctness regressions, may
cause performance regressions
* ACTION: Ulrich to backport to Linaro 4.4
* GCC test suite
* Michael asked what level of failures are acceptable
* Richard said that the FSF GCC has never been completely clean on ARM
* Failures may exist upstream
* In the future, should investigate all and fix
* For now, investigate regressions
* ACTION: Michael to build FSF 4.4.4 as a baseline
* ACTION: Michael to compare FSF and Linaro GCC failures
* ACTION: All Linaro GCC failures to be ticketed
* Regressions marked as 'test regression' with Medium severity
* Existing failures to be marked as 'test failure' with Low severity
* Wiki page [[Toolchain/UbuntuRegressions]] has triage from earlier
* Ulrich noted that fixing [[LP:500524]] in Linaro will overlap with
Ubuntu toolchain maintainer's current 4.4.4+svn patch
* Michael said that it is the responsibility of the Ubuntu
toolchain mainter to manage that
* Linaro will notify them on the change
* Discussed LTO
* Michael sees LTO tests fail on gcc-linaro-4.5 on ARM with
--enable-languages=c,c++
* Assumed it was binutils related
* Ulrich: shouldn't be as GCC does most of the work
* ACTION: Michael to reproduce
* Future work
* Focused on GCC at the moment
* Need medium term plan
* Focused on the core toolchain
* GCC
* Binutils
* GDB
* eglibc
* New hire specialises in qemu and will focus on that
* Multiarch is written up, unsure if we've agreed to do the work
* ACTION: Ulrich to write up known GDB work
* Medium severity tickets
* [[LP:598147]]
* May be three issues in one ticket
* Issues due to hardening, now fixed
* Stack crash due to invalid usage
* Extra test failures
* ACTION: Michael to reproduce the test failures
* [[LP:398403]]
* ACTION: Andrew to reproduce on his IGEP board (has more RAM)
* Ongoing work
* ACTION: Michael to make sure merge requests are present for work
that has been done
--- Yao:
== Linaro GCC 4.4 bug fix ==
* LP:604874.
Tried different set of configure/build options to reproduce
segfaults. Ulrich Weigand finally fixed this bug.
* LP:497295
It is about an ICE on maverick/arm. Reproduced ICE on maverick/x86.
ICE goes awy on linaro gcc, so it is not caused by linaro patches.
Finally, I find it is related to gcc-default-ssp.diff in Ubuntu.
Team decide to leave it as won't fix for 4.4, and get fix from
upstreams in 4.5.
* Issue #3314|LP:602288
Understand previous comments on this issue, and read something on
"address cost" in gcc. Looks like not easy to fix this problem.
* LP:612011|GCC PR45094
Create a patch against PR45094, and tested on ARM/QEMU. Post my
patch to gcc-patches first time in my life. A typo is found in my
patch. I fixed typo and submit a new patch again. Suggested to
run regression test again.
* LP:602285|Issue #5157
This bug is caused by our restrictions to the unrolling times.
Proposed two options to fix this bug. Waiting for the feedback from
the team.
== Misc ==
* Try gnu-checkout/gnu-devel/gnu-test for linaro toolchain
* Read doc on ARM ABI and procedure call standard
== This Week ==
* Get patches to PR45094 approved, and backport it for LP:612011.
* Discuss with team and choose one from two options to fix
LP:602285.
* Other bugs on launchpad.
--- Andrew:
== IGEPv2 ==
Continued with IGEPv2 board bringup. The OS that came with the board
proved inappropriate for creating Ubuntu Maverick chroots, so I looked
to updating the board. The IGEP website has tutorials on how to do
this using a tool called "rootstock".
It didn't take to long to get the board running with a more recent
kernel, but using an Ubuntu Lucid rootfs proved more problematic.
Getting a base system installed is not too hard, but that doesn't have
sshd or any other way to get in, and although serial output works,
serial input is broken, and I don't have a USB keyboard (imagine
that!) so using the video console is no good either.
Solved this problem by rebuilding a new rootfs that did have sshd in
it, and getting that setup right. Then installed all the new software
I wanted, set up a maverick chroot on NFS to work with, and gave Yao
and Chung-Lin access.
All was working well, so I took the SD card out, backed it up,
returned it to the board, and now it won't boot, again! To be
continued ....
== GCC 4.5 ==
Applied the first batch of SourceryG++ GCC 4.5 patches to the Linaro
sources, tested them, found them good, and pushed them to launchpad.
Applied another set of patches, and set them testing.
Marked all the patches in the CodeSourcery patch tracker that I
definitely won't be pushing to Linaro.
== Linaro patch tracker ==
Corresponded with Michael Hope regarding the Linaro patch tracker.
== Other ==
Finished getting the CodeSourcery build system to work with Launchpad,
and the Linaro GCC configurations.
-- Ulrich
== GCC ==
* Analyzed and fixed bug #604874 (Firefox fails to build)
- Fixed upstream (mainline, 4.5.2) as PR c++/45112
- Linaro GCC 4.4 branch merge request pending
* Analyzed and fixed bug #500525 (bootstrap failure in stage3)
- Backported mainline fix to upstream 4.4 branch
* Miscellaneous bug analysis / triage / comments on:
#437726, #608125, #607665, #505829, #600209
* Provided patch to revert CodeSourcery PowerPC changes from
Linaro GCC 4.4 (now merged).
== GDB ==
* Continued looking into GDB 7.2 test suite regressions
* Initial implementation of Thumb-2 support in ARM prologue parsing
== Miscellaneous ==
* Provided write-up of multiarch toolchain implications document
== Infrastructure ==
* Ordered IGEPv2 board
CS has this patch in SG++:
http://gcc.gnu.org/ml/gcc-patches/2008-12/msg00199.html
This patch improves code size in a useful, target independent way, but
was not committed upstream. It's not clear why. Since the patch does not
belong to CodeSourcery, we can't upstream it ourselves either.
Is that patch a suitable candidate for Linaro GCC?
It is not upstreamable due to copyright issues, but we have a policy
that we can keep such patches, if we wish.
The principle of not letting Linaro and SG++ diverge too far also
suggests keeping it.
Any thoughts? If nobody objects soon I shall merge it in.
Andrew
As already discussed with Loic, CodeSourcery have a GCC patch that
implements a new optimization: -fremove-local-statics.
Essentially, it transforms code like this:
int foo (void) { static int a = 1; return a; }
into this:
int foo (void) { int a = 1; return a; }
Admittedly, if the code is written like that you might argue that the
auther gets what they deserve, but apparently at least one of the EEMBC
benchmarks does have these, so now we all care about it.
This patch was originally submitted, by RedHat, to gcc-patches here:
http://gcc.gnu.org/ml/gcc-patches/2008-07/subjects.html#00982
Some discussion later, they decided it would be better to implement the
optimization using inter-procedural dead store analysis:
http://gcc.gnu.org/ml/gcc-patches/2008-07/msg01602.html
This doesn't seem to have actually been done. Not yet, anyway.
So basically we're left with this patch that does something we want, but
not in a way that can go upstream. :(
The question is, should I merge this to Linaro, or not? Loic and I
agreed to hold off until I'd done a bit more research and/or tried to
upstream it again, but now I think we need to think again.
Andrew
The agenda for todays call is available at:
https://wiki.linaro.org/WorkingGroups/ToolChain/Meetings/2010-08-02
The call will be on the usual code / numbers - I have the conference
code for doing a fully public call, but not the corresponding dial in
numbers.
See you then,
-- Michael
