1.\" Copyright (c) 2011 Kai Wang
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25.\" $Id: dwarf_add_AT_reference.3 3640 2018-10-14 14:09:13Z jkoshy $
26.\"
27.Dd September 4, 2011
28.Dt DWARF_ADD_AT_REFERENCE 3
29.Os
30.Sh NAME
31.Nm dwarf_add_AT_reference
32.Nd create and attach an attribute that references another DIE
33.Sh LIBRARY
34.Lb libdwarf
35.Sh SYNOPSIS
36.In libdwarf.h
37.Ft "Dwarf_P_Attribute"
38.Fo dwarf_add_AT_reference
39.Fa "Dwarf_P_Debug dbg"
40.Fa "Dwarf_P_Die die"
41.Fa "Dwarf_Half attr"
42.Fa "Dwarf_P_Die ref_die"
43.Fa "Dwarf_Error *err"
44.Fc
45.Sh DESCRIPTION
46Function
47.Fn dwarf_add_AT_reference
48creates an attribute descriptor that references another debugging
49information entry in the same compilation unit.
50The attribute will be of DWARF form
51.Dv DW_FORM_ref4
52or
53.Dv DW_FORM_ref8
54depending on the target address size, and will contain the
55section-relative offset of the referenced debugging information entry
56as its value.
57.Pp
58Argument
59.Ar dbg
60should reference a DWARF producer instance allocated using
61.Xr dwarf_producer_init 3
62or
63.Xr dwarf_producer_init_b 3 .
64.Pp
65Argument
66.Ar die
67should reference a debugging information entry allocated using
68.Xr dwarf_new_die 3 .
69.Pp
70Argument
71.Ar attr
72should specify the attribute code of the created attribute descriptor.
73.Pp
74Argument
75.Ar ref_die
76should hold the debugging information entry descriptor that
77the attribute should refer to.
78.Pp
79If argument
80.Ar err
81is not NULL, it will be used to store error information in case
82of an error.
83.Sh RETURN VALUES
84On success, function
85.Fn dwarf_add_AT_reference
86returns the created attribute descriptor.
87In case of an error, function
88.Fn dwarf_add_AT_reference
89returns
90.Dv DW_DLV_BADADDR
91and sets the argument
92.Ar err .
93.Sh ERRORS
94Function
95.Fn dwarf_add_AT_reference
96can fail with:
97.Bl -tag -width ".Bq Er DW_DLE_ARGUMENT"
98.It Bq Er DW_DLE_ARGUMENT
99One of the arguments
100.Ar dbg ,
101.Ar die
102or
103.Ar ref_die
104was NULL.
105.It Bq Er DW_DLE_MEMORY
106An out of memory condition was encountered during the execution of
107the function.
108.El
109.Sh SEE ALSO
110.Xr dwarf 3 ,
111.Xr dwarf_add_AT_dataref 3 ,
112.Xr dwarf_add_AT_ref_address 3 ,
113.Xr dwarf_add_AT_signed_const 3 ,
114.Xr dwarf_add_AT_unsigned_const 3 ,
115.Xr dwarf_new_die 3 ,
116.Xr dwarf_producer_init 3 ,
117.Xr dwarf_producer_init_b 3
118