dwarf2 - multiple DW_TAG_variable for global variable

[Nenad Vukicevic]

I installed gcc-4.5-20091224 snapshot and noticed that for simple 
variable declaration
I get two DW_TAG_variable dies in the object file. For example, the 
following
code

int xxxxx;
main()
{xxxxx=1;}

generates (with -g -gdwarf2 -O0 switches):

<1><54>: Abbrev Number: 4 (DW_TAG_variable)
<55>   DW_AT_name        : (indirect string, offset: 0x36): xxxxx
<59>   DW_AT_decl_file   : 1
<5a>   DW_AT_decl_line   : 1
<5b>   DW_AT_type        : <0x4d>
<5f>   DW_AT_external    : 1
<60>   DW_AT_declaration : 1
<1><61>: Abbrev Number: 5 (DW_TAG_variable)
<62>   DW_AT_name        : (indirect string, offset: 0x36): xxxxx
<66>   DW_AT_decl_file   : 1
<67>   DW_AT_decl_line   : 1
<68>   DW_AT_type        : <0x4d>
<6c>   DW_AT_external    : 1
<6d>   DW_AT_location    : 9 byte block: 3 0 0 0 0 0 0 0 0  (DW_OP_addr: 0)

Is the above normal? 4.3.2 compiler generates only one die, the second 
one with
DW_AT_location attribute, which is correct.

I also noticed that this example (were variable is not used):

int xxxxx;
main()
{}

generates only one DW_TAG_variable, the one  with DW_AT_location, which 
again
should be correct.

I ran into this problem by porting some GDB code that uses DWARF2 and 
got surprised
to see this change from the previous version of gcc (4.3).

Thanks,
Nenad