Re: Old bug with 'gdb/dbxread.c' and screwed up MIPS symbolic debugging...

[Andrew Cagney <ac131313 at cygnus dot com>]

> 
> Well, the change in objdump output is purely cosmetic.  For 32bit
> object formats we just truncate the display now.

As an aside, is there an option to turn this truncation off?  The vr5432 
as and ld will still pass around 64 bit addresses.

>> 
>> "SOLUTION"
>> ----------
>> On August 15, H.J. Lu applied a patch to 'gdb/dbxread.c' shown here:
>> 
>> diff -urN -x CVS work/gdb/dbxread.c gdb-5.0-08162001/gdb/dbxread.c
>> --- work/gdb/dbxread.c  Tue Oct 30 16:33:33 2001
>> +++ gdb-5.0-08162001/gdb/dbxread.c      Wed Aug 15 00:02:28 2001
>> @@ -951,7 +951,10 @@
>> (intern).n_type = bfd_h_get_8 (abfd, (extern)->e_type);            \
>> (intern).n_strx = bfd_h_get_32 (abfd, (extern)->e_strx);           \
>> (intern).n_desc = bfd_h_get_16 (abfd, (extern)->e_desc);           \
>> -    (intern).n_value = bfd_h_get_32 (abfd, (extern)->e_value);         \
>> +    if (bfd_get_sign_extend_vma
>> (abfd))                                       \
>> +      (intern).n_value = bfd_h_get_signed_32 (abfd,
>> (extern)->e_value);       \
>> +    else                                                               \
>> +      (intern).n_value = bfd_h_get_32 (abfd, (extern)->e_value);       \
>> }
>> > /* Invariant: The symbol pointed to by symbuf_idx is the first one
>> 
>> If I back out this change, my debug output is "correct", but I no longer
>> have the nice line numbers and files decoded for me:
> 
> 
> If you back it out, I believe we just give up in confusion  [:)] This is
> int the reading of stabs info.  breakinst has no stabs info, so it's
> getting its line info somewhere else.

It might - assembler debugging ...

> Please point me at a copy of your kernel binary with debug info, and
> I'll look into it.

Yes, you want to look for a version of breakinst that isn't sign 
extended.  Since pulling the above patch helped it won't be in .stabs so 
the symbol table?

Andrew