[Lldb-commits] [PATCH] D75750: WIP: [lldb] integrate debuginfod

[Jan Kratochvil via Phabricator via lldb-commits]

jankratochvil added inline comments.


================
Comment at: lldb/source/Host/common/DebugInfoD.cpp:59
+  char *cache_path = nullptr;
+  int rc = debuginfod_find_source(client, buildID.GetBytes().data(),
+                                  buildID.GetBytes().size(), path.c_str(),
----------------
labath wrote:
> fche2 wrote:
> > jankratochvil wrote:
> > > Here it will contact the server even if the binary does not contain any build-id - LLDB then generates UUID as 4 bytes long one:
> > > ```
> > >               // Use 4 bytes of crc from the .gnu_debuglink section.
> > >               u32le data(gnu_debuglink_crc);
> > >               uuid = UUID::fromData(&data, sizeof(data));
> > > ```
> > > That is a needless performance regression.
> > > I sure do not like making such decision on the LLDB side. Maybe libdebuginfod could rather make such optimization - IMO as Frank Eigler.
> > Could kkleine reject uuid of length 4 in the above test, i.e. something like:
> > 
> >     if (!uuid.IsValid() || uuid.GetBytes().size() == sizeof(u32le)) // .gnu_debuglink crc32
> >        continue;
> Ideally, lldb would not use the debug link crc as a uuid (and instead store that elsewhere), but rejecting the short uuids here does not seem _that_ bad.
We were discussing with @kwk that in fact sending anything stored in UUID as build-id may not be right. `debuginfod` wants specifically build-id, not any other identifier. Or @fche2 - does it? Would `debuginfod` for example accept some that Apple UUID for Apple dsym files? Maybe LLDB could store some identifier how was the UUID obtained.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D75750/new/

https://reviews.llvm.org/D75750