[PATCH] Add new debug kind LocTrackingOnly.

[David Blaikie]

On Mon, Jun 23, 2014 at 1:39 PM, Diego Novillo <dnovillo at google.com> wrote:
>
>
>
> On Mon, Jun 23, 2014 at 4:30 PM, David Blaikie <dblaikie at gmail.com> wrote:
>>
>> Looks good - though I'd prefer to separate the discussion about column
>> info so as to isolate the changes/tests/etc and not delay this review.
>>
>> ================
>> Comment at: lib/Frontend/CompilerInvocation.cpp:571
>> @@ +570,3 @@
>> +      Opts.setDebugInfo(CodeGenOptions::LocTrackingOnly);
>> +      Opts.DebugColumnInfo = true;
>> +    }
>> ----------------
>> Perhaps we could leave this out for now & just have a separate
>> CR/discussion about the semantics/ramifications of having this difference
>> between -R and -gmlt?
>
>
> Hm, perhaps. I would be penalizing -Rpass, however. But I guess it doesn't
> matter much. I'll amend the documentation to state that -gcolumn-inf is
> needed with -Rpass.

Well it's not worse - currently -Rpass doesn't enable debug info at
all , but I suppose it at least suggests the user enable both -gmlt
and -gcolumn-info. But I assume if they enabled -g(mlt or otherwise)
they wouldn't be told they should use -gcolumn-info.

So, committing this patch without the column info would be sort of a
regression, but sort of not... Given this is a developer feature only,
I'm OK with it being a little rough around the edges. Up to you
though, we can discuss the issues with -gcolumn-info and -Rpass in
this review if you prefer. Just figured it'd be better to separate
them if practical.

>> ================
>> Comment at: test/Frontend/optimization-remark.c:13
>> @@ +12,3 @@
>> +// CHECK: , !dbg !
>> +// CHECK-NOT: DW_TAG_base_type
>> +
>> ----------------
>> Could have a brief comment here "Ensure -Rpass, like -gmlt, doesn't
>> produce debug info metadata for types".
>
>
> That's what the comment above those two lines tries to do. Perhaps you want
> it worded differently?

Oh, no - that's fine. I'm just a bit myopic.