mingw/info/stabs/Transformations-On-Global-Variables.html

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  12 Node:<a name="Transformations%20On%20Global%20Variables">Transformations On Global Variables</a>,
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  19 <h4 class="subsection">Transformations on Global Variables</h4>
  20
  21    <p>Stabs for global variables do not contain location information. In
  22 this case, the debugger finds location information in the assembler or
  23 linker symbol table entry describing the variable.  The source line:
  24
  25 <pre class="example">     char g_foo = 'c';
  26      </pre>
  27
  28 <p>generates the stab:
  29
  30 <pre class="example">     .stabs "g_foo:G2",32,0,0,0
  31      </pre>
  32
  33    <p>The variable is represented by two symbol table entries in the object
  34 file (see below).  The first one originated as a stab.  The second one
  35 is an external symbol.  The upper case <code>D</code> signifies that the
  36 <code>n_type</code> field of the symbol table contains 7, <code>N_DATA</code> with
  37 local linkage.  The stab's value is zero since the value is not used for
  38 <code>N_GSYM</code> stabs.  The value of the linker symbol is the relocatable
  39 address corresponding to the variable.
  40
  41 <pre class="example">     00000000 - 00 0000  GSYM g_foo:G2
  42      00000080 D _g_foo
  43      </pre>
  44
  45 <p>These entries as transformed by the linker.  The linker symbol table
  46 entry now holds an absolute address:
  47
  48 <pre class="example">     00000000 - 00 0000  GSYM g_foo:G2
  49      ...
  50      0000e008 D _g_foo
  51      </pre>
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