* ld/testsuite/ld-arm/arm-merge-incompatiblea.s: Likewise.
* ld/testsuite/ld-arm/arm-merge-incompatibleb.s: Likewise.
* ld/testsuite/ld-arm/arm-elf.exp: Run the new test.
* bfd/elf32-arm.c (elf32_arm_merge_eabi_attributes): Add a check of the
return value from the call to _bfd_elf_merge_object_attributes.