ARM bfd Error: cannot represent BFD_RELOC_ARM_MOVW relocation in this object file format

[Nick Clifton]

Hi Pavel,

> I'm using cegcc (compiler for windows mobile) and if I compile for armv7 then I'll get everywhere tons off errors from assembler that
> Error: cannot represent BFD_RELOC_ARM_MOVW relocation in this object file format
> Error: cannot represent BFD_RELOC_ARM_MOVT relocation in this object file format
>
> This is because gcc generates movw/movt sequence instead of using a constant pool.

Which suggests that gcc could also be at fault for generating these 
instructions for a target which does not support them in this particular 
usage.  But anyway...

> Windows loader supports IMAGE_REL_BASED_HIGH and be IMAGE_REL_BASED_LOW which seems to be perfect match for BFD_RELOC_ARM_MOVW/BFD_RELOC_ARM_MOVT.
>
> So, my question is: how can I teach bfd/binutils to generate that kind of relocs for wince/arm-pe?

First you need to pick two numbers for these relocations.  Using the 
same numbers as IMAGE_REL_BASED_HIGH and IMAGE_REL_BASED_LOW would seem 
to be ideal.  Then you need to edit bfd/coff-arm.c and add support for 
these two new relocs.  (Note - you are working with COFF based support 
files here not ELF based ones.  That is probably why you did not find 
the code yourself).

Cheers
   Nick