blktrace fails to build on ARC

Hello ARC maintainers,

I don't know if you have noticed, but the blktrace package fails to build on ARC, since quite some time:

http://autobuild.buildroot.net/?reason=blktrace-1.%

There is a toolchain issue:

/home/test/autobuild/run/instance-2/output/host/opt/ext-toolchain/bin/../lib/gcc/arc-buildroot-linux-uclibc/7.3.1/../../../../arc-buildroot-linux-uclibc/bin/ld: btreplay: hidden symbol `__st_r13_to_r17' in /home/test/autobuild/run/instance-2/output/host/opt/ext-toolchain/bin/../lib/gcc/arc-buildroot-linux-uclibc/7.3.1/libgcc.a(_millicodethunk_st.o) is referenced by DSO /home/test/autobuild/run/instance-2/output/host/opt/ext-toolchain/bin/../lib/gcc/arc-buildroot-linux-uclibc/7.3.1/../../../../arc-buildroot-linux-uclibc/bin/ld: final link failed: Bad value

Could you have a look ?

Thanks,

Thomas

Thomas Petazzoni, CTO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com

Hello Thomas,

Recently due to a patch https://git.busybox.net/buildroot/commit/?id=5a3f78c9191595f7ea9fab49360dfc18a743d28b some packages were enabled for ARC. Four of them (blktrace, lvm2, gadgetfs-test and libioo) are building with error, which points to some issues with "millicode" optimizations in toolchain, which had not occurred before. Currently we are studying this problem.
As a temporal solution until the issue is not resolved these packages can be disabled for ARC or millicode optimizations can be disabled for ARC by adding such lines in package/Makefile.in:
--------------------------8<-------------------------------
ifeq ($(BR2_arc),y)
TARGET_ABI += -mno-millicode
endif
-------------------------->8----------------------------
What will be the best solution?

Best regards,
Evgeniy Didin

-----Original Message-----
From: Thomas Petazzoni <[email protected]>
Sent: Thursday, September 13, 2018 10:50 AM
To: ARC Maintainers <[email protected]>
Cc: buildroot at uclibc.org
Subject: [arc-buildroot] blktrace fails to build on ARC

Hello ARC maintainers,

I don't know if you have noticed, but the blktrace package fails to build on ARC, since quite some time:

https://urldefense.proofpoint.com/v2/url?u=http-3A__autobuild.buildroot.net_-3Freason-3Dblktrace-2D1.-25&d=DwICAg&c=DPL6_X_6JkXFx7AXWqB0tg&r=Z74rKOsEpOUneCxYxwKcXHwrAmW8mJhNZjcWnDDJI2U&m=QoMrXipN4E4JiIRskedh0eBRDMLw3VGNAzwubPXFQkI&s=-Yyh3kuQOOLeUIZA9XJClvgv6cP0toOcYwlWmrAb7Y0&e=

There is a toolchain issue:

/home/test/autobuild/run/instance-2/output/host/opt/ext-toolchain/bin/../lib/gcc/arc-buildroot-linux-uclibc/7.3.1/../../../../arc-buildroot-linux-uclibc/bin/ld: btreplay: hidden symbol `__st_r13_to_r17' in /home/test/autobuild/run/instance-2/output/host/opt/ext-toolchain/bin/../lib/gcc/arc-buildroot-linux-uclibc/7.3.1/libgcc.a(_millicodethunk_st.o) is referenced by DSO /home/test/autobuild/run/instance-2/output/host/opt/ext-toolchain/bin/../lib/gcc/arc-buildroot-linux-uclibc/7.3.1/../../../../arc-buildroot-linux-uclibc/bin/ld: final link failed: Bad value

Could you have a look ?

Thanks,

Thomas
--
Thomas Petazzoni, CTO, Bootlin
Embedded Linux and Kernel engineering
https://urldefense.proofpoint.com/v2/url?u=https-3A__bootlin.com&d=DwICAg&c=DPL6_X_6JkXFx7AXWqB0tg&r=Z74rKOsEpOUneCxYxwKcXHwrAmW8mJhNZjcWnDDJI2U&m=QoMrXipN4E4JiIRskedh0eBRDMLw3VGNAzwubPXFQkI&s=7PBj283fg5GRuQvaF7uozmGFB0Ec3aup005s545sEow&e=

Hello Evgeniy,

OK, thanks!

Do we really want to pass -mno-millicode to all packages? If only four packages are affected, what about adding this workaround to just those four packages?

Also, will you remember to remove this workaround in the future when the toolchain issue is fixed ? :-)

Thanks!

Thomas

Thomas Petazzoni, CTO, Bootlin
Embedded Linux and Kernel engineering
https://bootlin.com