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(stabs.info)Block Structure

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Block Structure
===============

   The program's block structure is represented by the `N_LBRAC' (left
brace) and the `N_RBRAC' (right brace) stab types.  The variables
defined inside a block precede the `N_LBRAC' symbol for most compilers,
including GCC.  Other compilers, such as the Convex, Acorn RISC
machine, and Sun `acc' compilers, put the variables after the `N_LBRAC'
symbol.  The values of the `N_LBRAC' and `N_RBRAC' symbols are the
start and end addresses of the code of the block, respectively.  For
most machines, they are relative to the starting address of this source
file.  For the Gould NP1, they are absolute.  For stabs in sections
(Note: Stab Sections), they are relative to the function in which
they occur.

   The `N_LBRAC' and `N_RBRAC' stabs that describe the block scope of a
procedure are located after the `N_FUN' stab that represents the
procedure itself.

   Sun documents the desc field of `N_LBRAC' and `N_RBRAC' symbols as
containing the nesting level of the block.  However, dbx seems to not
care, and GCC always sets desc to zero.

   For XCOFF, block scope is indicated with `C_BLOCK' symbols.  If the
name of the symbol is `.bb', then it is the beginning of the block; if
the name of the symbol is `.be'; it is the end of the block.