Stab-Section-Transformations.html 5.0 KB

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  63. <a name="Transformations-of-Stabs-in-separate-sections"></a>
  64. <h4 class="subsection">7.2.3 Transformations of Stabs in separate sections</h4>
  65. <p>For object file formats using stabs in separate sections (see <a href="Stab-Sections.html#Stab-Sections">Stab Sections</a>), use <code>objdump --stabs</code> instead of <code>nm</code> to show the
  66. stabs in an object or executable file. <code>objdump</code> is a GNU utility;
  67. Sun does not provide any equivalent.
  68. </p>
  69. <p>The following example is for a stab whose value is an address is
  70. relative to the compilation unit (see <a href="ELF-Linker-Relocation.html#ELF-Linker-Relocation">ELF Linker Relocation</a>). For
  71. example, if the source line
  72. </p>
  73. <div class="example">
  74. <pre class="example">static int ld = 5;
  75. </pre></div>
  76. <p>appears within a function, then the assembly language output from the
  77. compiler contains:
  78. </p>
  79. <div class="example">
  80. <pre class="example">.Ddata.data:
  81. &hellip;
  82. .stabs &quot;ld:V(0,3)&quot;,0x26,0,4,.L18-Ddata.data # <span class="roman">0x26 is N_STSYM</span>
  83. &hellip;
  84. .L18:
  85. .align 4
  86. .word 0x5
  87. </pre></div>
  88. <p>Because the value is formed by subtracting one symbol from another, the
  89. value is absolute, not relocatable, and so the object file contains
  90. </p>
  91. <div class="example">
  92. <pre class="example">Symnum n_type n_othr n_desc n_value n_strx String
  93. 31 STSYM 0 4 00000004 680 ld:V(0,3)
  94. </pre></div>
  95. <p>without any relocations, and the executable file also contains
  96. </p>
  97. <div class="example">
  98. <pre class="example">Symnum n_type n_othr n_desc n_value n_strx String
  99. 31 STSYM 0 4 00000004 680 ld:V(0,3)
  100. </pre></div>
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