[clang] [llvm] Generate `DW_AT_RUST_short_backtrace` attributes for `DISubprogram` nodes (PR #123683)

[via llvm-commits]

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@@ -605,6 +605,10 @@ HANDLE_DW_AT(0x3b28, BORLAND_Delphi_ABI, 0, BORLAND)
 HANDLE_DW_AT(0x3b29, BORLAND_Delphi_return, 0, BORLAND)
 HANDLE_DW_AT(0x3b30, BORLAND_Delphi_frameptr, 0, BORLAND)
 HANDLE_DW_AT(0x3b31, BORLAND_closure, 0, BORLAND)
+
+// Rust extensions.
+HANDLE_DW_AT(0x3c00, RUST_short_backtrace, 0, RUST)
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jyn514 wrote:

DWARF has a general mechanism for vendor extensions. No matter what we do, this won't be in the DWARF 5 standard, which has already been published. But if it's used widely enough, there's a chance it makes it into DWARF 6 or 7. I don't think that depends very much on the naming of the attribute though.

https://github.com/llvm/llvm-project/pull/123683