mingw/info/stabs/Stab-Section-Transformations.html

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  12 Node:<a name="Stab%20Section%20Transformations">Stab Section Transformations</a>,
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  17
  18 <h4 class="subsection">Transformations of Stabs in separate sections</h4>
  19
  20    <p>For object file formats using stabs in separate sections (see <a href="Stab-Sections.html#Stab%20Sections">Stab Sections</a>), use <code>objdump --stabs</code> instead of <code>nm</code> to show the
  21 stabs in an object or executable file.  <code>objdump</code> is a GNU utility;
  22 Sun does not provide any equivalent.
  23
  24    <p>The following example is for a stab whose value is an address is
  25 relative to the compilation unit (see <a href="ELF-Linker-Relocation.html#ELF%20Linker%20Relocation">ELF Linker Relocation</a>).  For
  26 example, if the source line
  27
  28 <pre class="example">     static int ld = 5;
  29      </pre>
  30
  31    <p>appears within a function, then the assembly language output from the
  32 compiler contains:
  33
  34 <pre class="example">     .Ddata.data:
  35      ...
  36              .stabs "ld:V(0,3)",0x26,0,4,.L18-Ddata.data    # 0x26 is N_STSYM
  37      ...
  38      .L18:
  39              .align 4
  40              .word 0x5
  41      </pre>
  42
  43    <p>Because the value is formed by subtracting one symbol from another, the
  44 value is absolute, not relocatable, and so the object file contains
  45
  46 <pre class="example">     Symnum n_type n_othr n_desc n_value  n_strx String
  47      31     STSYM  0      4      00000004 680    ld:V(0,3)
  48      </pre>
  49
  50    <p>without any relocations, and the executable file also contains
  51
  52 <pre class="example">     Symnum n_type n_othr n_desc n_value  n_strx String
  53      31     STSYM  0      4      00000004 680    ld:V(0,3)
  54      </pre>
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