On Sun, 30 Aug 2020 19:18:51 +0200, Mark Wielaard wrote:
> During the BoF Pedro mentioned that the GDB DWARF5 .debug_names support
> is incomplete/wrong. I was wondering whether there was a good
> description of the issue and/or a bug report for it. When using the
> contrib/gdb-add-index.sh it does add a .gdb_index for objects
> containing DWARF5 and the results seem correct, gdb also seems to be
> able to use it. When adding -dwarf-5 it seems to output a .debug_names
> section which can be read by binutils readelf (elfutils doesn't yet
> support .debug_names). I couldn't immediately see in what way it was
> wrong/incomplete.

.debug_names from GDB needs to produce also DW_IDX_die_offset to make it
consumable by debuggers with reasonable performance.

Then I see clang++ -gdwarf-5 -gpubnames produces C++ names mangled while GDB
produces them unmangled. I haven't found anything in DWARF-5 standard
suggesting either. Given mangled->unmangled mapping is possible but
unmangled->mangled is not (such as variants of ctors/dtors) I find the clang
way should be followed.


Jan