Discussion on D support in gdb

[Martin Nowak]

On Fri, 25 Nov 2011 04:13:18 +0100, Walter Bright  
<newshound2 at digitalmars.com> wrote:

> On 11/22/2011 7:19 AM, Martin Nowak wrote:
>> - Can we slowly start to acquire DWARF-3/4?
>
> Dwarf 2 is good enough, so why do 3/4?
>
>> - Why were extensions chosen over say representing an array as two  
>> field struct?
>
> Because it is presumably harder to get a debugger to recognize a magic  
> struct than explicitly give it a type.
>
Dwarf-4 supports arbitrary expressions for array base addresses and the  
upper bound,
one could directly translate D arrays. GDB doesn't support it at the  
moment,
but it basically rules out requesting an extension to the DWARF standard.

I think currently the best decision is to use the existing D support in  
GDB.

C++0x will likely lead to extended support in GDB, while llvm-db should
improve the OSX debugger support.
With better support for the new formats we should be able to express  
specific D
constructs in DWARF.

>> - There is this request by Robert Clipsham
>> http://dwarfstd.org/ShowIssue.php?issue=100504.1.
>> What's the state of this, it wouldn't be needed any longer.
>>
>> - We should contact http://www.zero-bugs.com, it is said to support the
>> dwarf extensions and would need to be changed.
>>
>> - Find out who else is affected by changing the current extensions.
>>
>> - Fixing the D-ABI specification.
>
> Are the issues in bugzilla?
>
>> - Are there other DWARF debuggers that we should take into account?
>>
>> - Adding a page to GNU wiki describing the D extensions.
>>
>> - We could probably use DW_TAG_GNU_template_parameter_pack for variadic  
>> template
>> arguments.
>> http://wiki.dwarfstd.org/index.php?title=C%2B%2B0x:_Variadic_templates
>>
>> martin