Re: does Valgrind-3.19.0.GIT support Clang14 dwarf 5?

On Wed, Feb 16, 2022 at 12:46:32PM +0900, ISHIKAWA,chiaki wrote:
> This is tangent to the original question, but this part:
> 
> > with split-dwarf (which rnglistx and strx
> form codes doesn't support yet)
>
> valgrind does support bulk of data generated by --split-dwarf (gcc),
> doesn't it?

No, it doesn't. valgrind won't read .dwo files/sections at all which
split-dwarf uses.

> The above refers to "doesn't support"  rnglistx and strx form codes?

And addrx forms. These are normally only used (by gcc) for split-dwarf
and involve an extra indirection through an index to reach the value
of the attribute. These forms are technically valid in non-split-dwarf
(with DWARF5) but not supported by valgrind.

> I am asking this  because I have checked mozilla thunderbird code
> which is compiled using --split-dwarf of GCC and valgrind reports
> reasonably sane diagnosis so far.

valgrind can report valid diagnostics with DWARF debuginfo, but it
might be less accurate, for example it won't report on inlined
functions.

I happened to give a talk on that recently:
https://fosdem.org/2022/schedule/event/valgrind_debuginfo/
(That talk doesn't cover split-dwarf though)

Cheers,

Mark