[llvm] [DWARFVerifier] Fix debug_str_offsets DWARF version detection (PR #81303)

[Felipe de Azevedo Piovezan via llvm-commits]

felipepiovezan wrote:

> > However, the verifier supports some pre-standardization version of this section (with the same section name), which does not have a header. In this case, the offsets start on the first byte of the section, although it's not clear where this is documented.
> 
> https://gcc.gnu.org/wiki/DebugFission and https://gcc.gnu.org/wiki/DebugFissionDWP is where this pre-standard stuff was documented

Thank you for the pointers! I will update the commit message. Is the patch itself ok?

https://github.com/llvm/llvm-project/pull/81303