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  15. <title>Transformations On Global Variables (STABS)</title>
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  62. <a name="Transformations-on-Global-Variables"></a>
  63. <h4 class="subsection">7.2.2 Transformations on Global Variables</h4>
  64. <p>Stabs for global variables do not contain location information. In
  65. this case, the debugger finds location information in the assembler or
  66. linker symbol table entry describing the variable. The source line:
  67. </p>
  68. <div class="example">
  69. <pre class="example">char g_foo = 'c';
  70. </pre></div>
  71. <p>generates the stab:
  72. </p>
  73. <div class="example">
  74. <pre class="example">.stabs &quot;g_foo:G2&quot;,32,0,0,0
  75. </pre></div>
  76. <p>The variable is represented by two symbol table entries in the object
  77. file (see below). The first one originated as a stab. The second one
  78. is an external symbol. The upper case &lsquo;<samp>D</samp>&rsquo; signifies that the
  79. <code>n_type</code> field of the symbol table contains 7, <code>N_DATA</code> with
  80. local linkage. The stab&rsquo;s value is zero since the value is not used for
  81. <code>N_GSYM</code> stabs. The value of the linker symbol is the relocatable
  82. address corresponding to the variable.
  83. </p>
  84. <div class="example">
  85. <pre class="example">00000000 - 00 0000 GSYM g_foo:G2
  86. 00000080 D _g_foo
  87. </pre></div>
  88. <p>These entries as transformed by the linker. The linker symbol table
  89. entry now holds an absolute address:
  90. </p>
  91. <div class="example">
  92. <pre class="example">00000000 - 00 0000 GSYM g_foo:G2
  93. &hellip;
  94. 0000e008 D _g_foo
  95. </pre></div>
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