[PATCH] D68465: [DebugInfo] Trim call-clobbered location list entries when tuning for GDB

[David Blaikie via Phabricator via llvm-commits]

dblaikie added a comment.

Thanks for bringing this up!

A few thoughts from me:

1. Yeah, I tend to agree with the DWARF Committee folks & the fact that LLDB can do the right thing without this change sort of points to this being a "fix it in GDB" situation. Have you tried asking the GDB folks about it/submitting patches there rather than here?

2. Do you have a small example of GCC producing this kind of output?

3. The ability to use an offset from a debug_addr entry is actually something that's quite desirable - but not quite in the way you're suggesting. Actually the goal would be to not use another debug_addr entry, but the ability to refer to an addr entry + offset in a DIE. Of course this would require an extension to DWARF (non-standard, or eventually standard) which would also mean updating the DWARF consumer... which probably defeats the point of your work, which I imagine is intended to avoid changing the consumer. Though perhaps GDB would be more inclined to accept a patch for an addr+offset form compared to support for the register details.

4. If GDB can do the right thing when printing in a backtrace, then it seems like it should do the same/similar thing when in a frame


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