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<p class="MsoNormal">Hello,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The ObjectFile class (in Object/ObjectFile.h) presents a format-independent interface for object files. In addition, for COFF and MachO, some internal format details are exposed in special headers. For example, Object/COFF.h exposes coff_file_header
and coff_symbol. Object/MachOFormat.h exposes headers, “segment load commands” and so on.<o:p></o:p></p>
<p class="MsoNormal">ELF, however, is not exposed and completely hidden behind the ObjectFile.h interface.<o:p></o:p></p>
<p class="MsoNormal">My questions is – what is the reasoning behind this design, which apparently takes 2 different approaches. Is the intention to eventually have everything hidden like in the ELF case, or selectively exposed, like for COFF and MachO?<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The motivation for my question is a dynamic loader in MC-JIT for ELF. The current RuntimeDyldMachO uses structures exposed outside the ObjectFile interface (for example, macho::SymtabLoadCommand) to do its work. When working on RuntimeDyldELF,
I encountered some cases of Elf information I need which wasn’t exposed through the ObjectFile interface. Adding additional getters to that interface requires to implement them in COFF and MachO object files as well (perhaps returning “not_implemented” error
codes).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">So, I’m wondering whether the right approach here is to keep everything behind the ObjectFile interface, or just expose some ELF specific structures via a header file and use those? After all, this is in code that is specifically meant
to handle ELF files, so it makes some sense to have a better understanding of ELF for such code, and not only a generic understanding exposed through ObjectFile.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks in advance,<o:p></o:p></p>
<p class="MsoNormal">Eli<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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