Don't merge vtables when full debuginfo is enabled. #107373
Merged
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This PR makes the compiler not emit the
unnamed_addr
attribute for vtables when full debuginfo is enabled, so that they don't get merged even if they have the same contents. This allows debuggers to more reliably map from a dyn pointer to the self-type of a trait object by looking at the vtable's debuginfo.The PR only changes the behavior of the LLVM backend as other backends don't emit vtable debuginfo (as far as I can tell).
The performance impact of this change should be small as measured in a previous PR.