llvm dev - Jun 2008 - [LLVMdev] Debugging with llvm-gcc/mingw doesn't seem to work

Hello, Argiris
> Any ideas?
1. Make sure, that you don't mix dwarf and stabs debug information.
AFAIR, this can really mess the things
2. It can be, that debug information emitted is not correct. This is
known open problem.

-- 
With best regards, Anton Korobeynikov.

Faculty of Mathematics & Mechanics, Saint Petersburg State University.

Anton Korobeynikov wrote:
> 2. It can be, that debug information emitted is not correct. This is
> known open problem.
>   
I assume it is known problem for llvm-gcc in general and not only the 
mingw version, is this correct ?
I say that because I tried the linux binaries and they have the same issue.


-Argiris

Anton Korobeynikov wrote:
> 2. It can be, that debug information emitted is not correct. This is
> known open problem.
>   
The attached patch fixes the problem with the line information.

For the "AT_stmt_list" attribute of the compilation unit entry,
DWARF-2
specification says:
> A DW_AT_stmt_list attribute whose value is a reference to line number 
> information for
> this compilation unit.
> This information is placed in a separate object file section from the 
> debugging information
> entries themselves. The value of the statement list attribute is the 
> offset in the
> .debug_line section of the first byte of the line number information 
> for this compilation
> unit
DwarfWriter was using a label reference (instead of a section offset) 
and it was causing a problem because Windows treats
section offsets differently, by emitting the ".secrel32" directive.


-Argiris

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Looks good, please commit.

Evan

On Jun 16, 2008, at 11:32 PM, Argiris Kirtzidis wrote:
> Anton Korobeynikov wrote:
>> 2. It can be, that debug information emitted is not correct. This is
>> known open problem.
>>
>
> The attached patch fixes the problem with the line information.
>
> For the "AT_stmt_list" attribute of the compilation unit entry,  
> DWARF-2 specification says:
>
>> A DW_AT_stmt_list attribute whose value is a reference to line  
>> number information for
>> this compilation unit.
>> This information is placed in a separate object file section from  
>> the debugging information
>> entries themselves. The value of the statement list attribute is  
>> the offset in the
>> .debug_line section of the first byte of the line number  
>> information for this compilation
>> unit
>
> DwarfWriter was using a label reference (instead of a section  
> offset) and it was causing a problem because Windows treats
> section offsets differently, by emitting the ".secrel32"
directive.
>
>
> -Argiris
>
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