[LLVMdev] Debug Information for LLVM 2.6 and TOT

[Devang Patel]

Hi John,

On Wed, Nov 4, 2009 at 12:04 PM, John Criswell <criswell at uiuc.edu> wrote:
> Dear All,
>
> 1) I recall reading somewhere that a few optimizations in LLVM 2.6 strip
> away debug information when such information interferes with
> optimization.  Is this correct,

Yes.

> and if so, does anyone know off-hand
> which optimizations do this?

The optimizer does not emit any statistics here. You can search
various transformation passes' code to see whether they are handling
DbgInfoIntrinsics or not. Or may be I misunderstood your question ?

> 2) I believe a new debug annotation design is being implemented in
> mainline LLVM for the 2.7 release.  What is the current status of this
> work?  Does it already yield more accurate debug information than LLVM 2.6?

It is still a work in progress. However, now it yields better scoping
information when clang FE is used to generate debug info.

-
Devang