Going through Olof's build report for 4.19.y:

On Thu, Jul 4, 2019 at 12:14 PM Olof's autobuilder build@lixom.net wrote:

    arm.rpc_defconfig:

arm-unknown-linux-gnueabi-gcc: error: unrecognized -march target: armv3m arm-unknown-linux-gnueabi-gcc: error: missing argument to '-march=' arm-unknown-linux-gnueabi-gcc: error: unrecognized -march target: armv3m arm-unknown-linux-gnueabi-gcc: error: missing argument to '-march='

No mainline patch yet, this happens with gcc-9, which cannot build an rpc kernel any more as armv3 support got dropped:

arch/arm/mm/init.c:471:13: warning: unused variable 'itcm_end' [-Wunused-variable] arch/arm/mm/init.c:470:13: warning: unused variable 'dtcm_end' [-Wunused-variable]

Please backport this to 5.1-stable:

e6c4375f7c92 ("ARM: 8865/1: mm: remove unused variables")

/tmp/ccUhzzYK.s:18119: Warning: using r15 results in unpredictable behaviour /tmp/ccUhzzYK.s:18191: Warning: using r15 results in unpredictable behaviour

I have a patch but not mainlined it yet.

sound/pci/echoaudio/echoaudio_dsp.c:647:9: warning: iteration 1073741824 invokes undefined behavior [-Waggressive-loop-optimizations] sound/pci/echoaudio/echoaudio_dsp.c:658:9: warning: iteration 1073741824 invokes undefined behavior [-Waggressive-loop-optimizations] sound/pci/echoaudio/echoaudio_dsp.c:647:9: warning: iteration 1073741824 invokes undefined behavior [-Waggressive-loop-optimizations]

Have not seen this one yet, sorry.

include/linux/string.h:340:9: warning: '__builtin_memset' offset [321, 344] from the object at 'buf' is out of the bounds of referenced subobject 'rdata' with type 'struct fc_rport_priv' at offset 0 [-Warray-bounds] include/linux/string.h:340:9: warning: '__builtin_memset' offset [321, 344] from the object at 'buf' is out of the bounds of referenced subobject 'rdata' with type 'struct fc_rport_priv' at offset 0 [-Warray-bounds]

Looks like a harmless warning from an unusal coding style. The issue is still present in mainline and should be trivial to address by anyone using gcc-9.

include/linux/module.h:132:6: warning: 'init_module' specifies less restrictive attribute than its target 'rp_init': 'cold' [-Wmissing-attributes]

Please backport this to all stable kernels (2.6.39+):

423ea3255424 ("tty: rocket: fix incorrect forward declaration of 'rp_init()'"

    arm64.allmodconfig:

drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_n.c:16563:1: warning: the frame size of 2592 bytes is larger than 2048 bytes [-Wframe-larger-than=] drivers/net/wireless/broadcom/brcm80211/brcmsmac/phy/phy_n.c:16905:1: warning: the frame size of 2560 bytes is larger than 2048 bytes [-Wframe-larger-than=]

My patch is waiting for mainline acceptance:

https://patchwork.kernel.org/patch/11022355/

aarch64-unknown-linux-gnu-ld: warning: creating a DT_TEXTREL in object aarch64-unknown-linux-gnu-ld: warning: creating a DT_TEXTREL in object aarch64-unknown-linux-gnu-ld: warning: creating a DT_TEXTREL in object

no idea, I don't see this here.

    i386.allmodconfig:

drivers/iio/adc/rcar-gyroadc.c:510:5: warning: 'ret' may be used uninitialized in this function [-Wmaybe-uninitialized]

Yep, that's a bug, just sent a fix now.: https://lore.kernel.org/lkml/20190704113800.3299636-1-arnd@arndb.de/

Arnd