newlib and -mthumb-interwork

J. Johnston
Tue Dec 11 15:05:00 GMT 2001

wearpos wrote:
> Hi
> I have the same problem as discussed already on this list:
> I read this thread but didn't find an answer to my question. But basicaly my
> problem is realy the same.
> I wanna mix arm-32-bit code with arma-16-bit code.
> I built newest gcc version 3.0.2 using together with newlib 1.9
> I configured newlib using --target=arm-elf. After make there were two libs
> ..../arm-elf/lib/libc.a and
> .../arm-elf/lib/thumb/libc.a
> but if i try to link using on of these libs linker tells me:
> /usr/local/bin/arm-elf-ld: Warning: memcpy.o does not support interworking,
> whereas wearpos.elf  does not.
> In the posting mentioned above Jeff J. worte to call gcc
> with -print-multi-lib.
> H:\Semesterarbeit\Software\wearpos>d:\cygwin\usr\local\bin\arm-elf-gcc -prin
> t-multi-lib
> .;
> thumb;@mthumb
> but what the hell dows this mean.

This means that the compiler supports two multilibs.  One default options and
the other with the -mthumb option specified.  Note, no thumb-interwork multilib

The arm-elf gcc compiler which was shipped as part of the Cygnus progressive
has a lot more multilibs, including thumb-interwork.  I suggest you contact the
mailing list to see why thumb-interwork is not included in your particular

-- Jeff J.

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