Untitled Document: Relocating the section contents

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#### 2.17.3.2 Relocating the section contents

The `_bfd_final_link` function should look through the `link_order` structures attached to each section of the output file. Each `link_order` structure should either be handled specially, or it should be passed to the function `_bfd_default_link_order` which will do the right thing (`_bfd_default_link_order` is defined in `linker.c`).

For efficiency, a `link_order` of type `bfd_indirect_link_order` whose associated section belongs to a BFD of the same format as the output BFD must be handled specially. This type of `link_order` describes part of an output section in terms of a section belonging to one of the input files. The `_bfd_final_link` function should read the contents of the section and any associated relocs, apply the relocs to the section contents, and write out the modified section contents. If performing a relocatable link, the relocs themselves must also be modified and written out.

The functions `_bfd_relocate_contents` and `_bfd_final_link_relocate` provide some general support for performing the actual relocations, notably overflow checking. Their arguments include information about the symbol the relocation is against and a `reloc_howto_type` argument which describes the relocation to perform. These functions are defined in `reloc.c`.

The a.out function which handles reading, relocating, and writing section contents is `aout_link_input_section`. The actual relocation is done in `aout_link_input_section_std` and `aout_link_input_section_ext`.