Passing -gdwarf-5 generates neither .apple_names nor .debug_names

[JDevlieghere]

On Apple platforms, we generate .apple_names, .apple_types, .apple_namespaces and .apple_objc Apple accelerator tables for DWARF 4 and earlier. For DWARF 5, I would expect us to generate .debug_names, but instead we get no accelerator tables at all.

In the backend we are correctly determining that we should be emitting .debug_names instead of .apple_names. However, when we get to the point of emitting the section, CU debug name table kind is not "default" are skipped . This property is controlled by the -gpubnames argument. Indeed, passing -gdwarf-5 -gpubnames does generate .debug_names section, on all platforms.

On Apple platforms, the .debug_names section should be emitted by default.

[llvmbot]

@llvm/issue-subscribers-debuginfo

[JDevlieghere]

CC @adrian-prantl @labath @dwblaikie @clayborg

[dwblaikie]

yep - makes sense to enable them by default when tuning for lldb I guess - not sure whether that would be implemented in clang or llvm, I forget where some of those determinations are made (I'd somewhat advocate for made in clang, so users could opt-out somehow, like -gno-pubnames might still override the tuning default, for instance)