A separate debuginfo file is a special animal and I don't think we should expect that every random thing that handles fully-formed ELF files will handle debuginfo files without being confused.
I think extra header bits and such are a rat-hole of effort, hassle, and slow deployment, with very little payoff. I'm against that idea. Heuristically, a separate debuginfo file with phdrs can be recognized by there being SHT_NOBITS sections whose sh_addr places them in parts of PT_LOAD segments that cannot be the bss-like case. If any section with SHT_NOBITS,SHF_ALLOC has its sh_addr fall inside the range [p_vaddr, p_vaddr+p_filesz) of a PT_LOAD segment, it's either a debuginfo file or a malformed oddball.
