[clang] [llvm] [dwarf] make dwarf fission compatible with RISCV relaxations (PR #164128)

[David Spickett via llvm-commits]

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+; RUN: llc -dwarf-version=5 -split-dwarf-file=foo.dwo -O0 %s -mtriple=riscv64-unknown-linux-gnu -filetype=obj -o %t
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DavidSpickett wrote:

> As far as I know, Split DWARFv4 doesn't exist, as DWARF fission was initially introduced only in DWARFv5.

I don't know if this helps or hinders your point but gcc and clang when asked for split dwarf will use `DW_AT_GNU_dwo_name` for dwarf <=4 and `DW_AT_dwo_name` for >=5.

First appearance of `DW_AT_dwo_name` is in the standard for DWARF 5, that's for sure.

https://github.com/llvm/llvm-project/pull/164128