[Bug debug/45973] New: NRVO gives incorrect location

[tromey at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=45973

           Summary: NRVO gives incorrect location
           Product: gcc
           Version: 4.6.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: debug
        AssignedTo: unassig...@gcc.gnu.org
        ReportedBy: tro...@gcc.gnu.org


This test case comes from gdb bugzilla.

class foo
{
public:
    int bar;
    ~foo(){};
};

foo f()
{
    foo x;
    x.bar = 1;
    x.bar = x.bar;
    return x;
};

int main()
{
    f();
};


Compile with -g.  Then, look at 'x' in the DWARF.  I see:

 <3><cf>: Abbrev Number: 15 (DW_TAG_variable)
    <d0>   DW_AT_name        : x    
    <d2>   DW_AT_decl_file   : 1    
    <d3>   DW_AT_decl_line   : 10    
    <d4>   DW_AT_type        : <0x29>    
    <d8>   DW_AT_location    : 1 byte block: 52     (DW_OP_reg2)

I think this is missing a DW_OP_deref.
That is, I think reg2 points to the object, it doesn't hold the object.