mingw/info/stabs/Block-Structure.html

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  12 Node:<a name="Block%20Structure">Block Structure</a>,
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  19 <h3 class="section">Block Structure</h3>
  20
  21    <p>The program's block structure is represented by the <code>N_LBRAC</code> (left
  22 brace) and the <code>N_RBRAC</code> (right brace) stab types.  The variables
  23 defined inside a block precede the <code>N_LBRAC</code> symbol for most
  24 compilers, including GCC.  Other compilers, such as the Convex, Acorn
  25 RISC machine, and Sun <code>acc</code> compilers, put the variables after the
  26 <code>N_LBRAC</code> symbol.  The values of the <code>N_LBRAC</code> and
  27 <code>N_RBRAC</code> symbols are the start and end addresses of the code of
  28 the block, respectively.  For most machines, they are relative to the
  29 starting address of this source file.  For the Gould NP1, they are
  30 absolute.  For stabs in sections (see <a href="Stab-Sections.html#Stab%20Sections">Stab Sections</a>), they are
  31 relative to the function in which they occur.
  32
  33    <p>The <code>N_LBRAC</code> and <code>N_RBRAC</code> stabs that describe the block
  34 scope of a procedure are located after the <code>N_FUN</code> stab that
  35 represents the procedure itself.
  36
  37    <p>Sun documents the desc field of <code>N_LBRAC</code> and
  38 <code>N_RBRAC</code> symbols as containing the nesting level of the block.
  39 However, dbx seems to not care, and GCC always sets desc to
  40 zero.
  41
  42    <p>For XCOFF, block scope is indicated with <code>C_BLOCK</code> symbols.  If the
  43 name of the symbol is <code>.bb</code>, then it is the beginning of the block;
  44 if the name of the symbol is <code>.be</code>; it is the end of the block.
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