[oe] klibc: armv4 bx strikes again

[Khem Raj]

On 14-08-26 11:36:34, Andrea Adami wrote:
> On Mon, Aug 25, 2014 at 10:08 AM, Andrea Adami <andrea.adami at gmail.com> wrote:
> > I've recently discovered that the static klibc binaries produced for
> > armv4 contain Illegal instructions.
> >
> > Eglibc armv4 binaries are ok.
> >
> > I verified it happens to kexec-tools-klibc and kexecboot-klibc:
> >
> > andrea at mizar:/oe/oe-core/build/tmp-eglibc/sysroots/x86_64-linux/usr/bin/arm-oe-linux-gnueabi$
> > ./arm-oe-linux-gnueabi-objdump -S ./kexecboot-armv4 | grep bx
> >    110dc:       012fff1e        bxeq    lr
> >    11154:       e12fff1e        bx      lr
> >    11160:       e12fff1e        bx      lr
> >    11170:       e12fff1e        bx      lr
> >    1119c:       e12fff1e        bx      lr
> >    11234:       e12fff1e        bx      lr
> >    11240:       e12fff1e        bx      lr
> >    11250:       e12fff1e        bx      lr
> >    11268:       e12fff1e        bx      lr
> >    11298:       e12fff1e        bx      lr
> >    112b4:       e12fff1e        bx      lr
> >    112f0:       e12fff1e        bx      lr
> >    115f4:       e12fff1e        bx      lr
> > andrea at mizar:/oe/oe-core/build/tmp-eglibc/sysroots/x86_64-linux/usr/bin/arm-oe-linux-gnueabi$
> >
> > The binaries end-up compiled with following flags:
> >
> > arm-oe-linux-gnueabi-klcc -march=armv4 -mthumb-interwork -Wall    -o
> > kexecboot util.o cfgparser.o devicescan.o evdevs.o fb.o gui.o menu.o
> > xpm.o rgb.o tui.o kexecboot.o fstype/fstype.o machine/zaurus.o

what is content of arm-oe-linux-gnueabi-klcc ? is it also used at link
step ? the option 

> >
> > This is rather unexpected because klibc carries one specific patch to fix that:
> >
> > http://cgit.openembedded.org/meta-openembedded/tree/meta-initramfs/recipes-devtools/klibc/klibc-2.0.4/armv4-fix-v4bx.patch
> >
> > and in fact looking at the produced klibc.config I see indeed LDFLAGS=
> > --fix-v4bx and that goes in  *arm-oe-linux-gnueabi-klcc.
> >
> > There have been big toolchain changes recently so I suspect something
> > got broken in oe-core.
> > Then there is a patch touching armv4/thumb but it doesn't look
> > suspicious at first:
> >
> > http://cgit.openembedded.org/openembedded-core/commit/meta/conf/machine/include?id=1250d3e009363d20f15bbfaced622c5912a7fb93
> >

for tests
can you use FIX_V4BX_ARMV4 in
meta-initramfs/recipes-devtools/klibc/klibc.inc 
and see if it helps