Re: commitment to DWARF2 debugging information

[Daniel Berlin <dan at cgsoftware dot com>]

On Mon, 5 Jun 2000, Jim Wilson wrote:

> 
> Upside:
> DWARF2 is the preferred debug info format for C++ programs.
> DWARF2 is the only debug info format supported for IA-64.
> Linux is using DWARF2 for Sparc64 as the default debug info format.
> Cygnus recommends ELF/DWARF2 for all new ports.
> 
> Downside:
> Full DWARF2 support requires a little machine dependent support.  This support
> has not been written for PPC yet.
> The DWARF2 support does not eliminate duplicate header file debug info.  The
> STABS support does.  This can result in large debug info size increases if you
> have a program where every source file includes every header file.  This is
> particularly common for some C++ programming styles.  I believe some work is
> being done on this, but I don't know what the status is.


As a note, I just today committed a patch to GDB to remove duplicate type 
info when we read in the DWARF2 info (or at least, the majority. You could
probably improve upon what i've done at a horrendous cost in memory and
performance, and gain 3-4% more memory savings), which we weren't doing
before. I consider this a stopgap until LD does the same type of thing.

However, it should give you a very large reduction in memory usage while
debugging with DWARF2.

> 
> Jim
>