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(stabs.info)Stack Variables

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Automatic Variables Allocated on the Stack
==========================================

   If a variable's scope is local to a function and its lifetime is
only as long as that function executes (C calls such variables
"automatic"), it can be allocated in a register (Note: Register
Variables) or on the stack.

   Each variable allocated on the stack has a stab with the symbol
descriptor omitted.  Since type information should begin with a digit,
`-', or `(', only those characters precluded from being used for symbol
descriptors.  However, the Acorn RISC machine (ARM) is said to get this
wrong: it puts out a mere type definition here, without the preceding
`TYPE-NUMBER='.  This is a bad idea; there is no guarantee that type
descriptors are distinct from symbol descriptors.  Stabs for stack
variables use the `N_LSYM' stab type, or `C_LSYM' for XCOFF.

   The value of the stab is the offset of the variable within the local
variables.  On most machines this is an offset from the frame pointer
and is negative.  The location of the stab specifies which block it is
defined in; see Note: Block Structure.

   For example, the following C code:

     int
     main ()
     {
       int x;
     }

   produces the following stabs:

     .stabs "main:F1",36,0,0,_main   # 36 is N_FUN
     .stabs "x:1",128,0,0,-12        # 128 is N_LSYM
     .stabn 192,0,0,LBB2             # 192 is N_LBRAC
     .stabn 224,0,0,LBE2             # 224 is N_RBRAC

   See Note: Procedures for more information on the `N_FUN' stab, and
Note: Block Structure for more information on the `N_LBRAC' and
`N_RBRAC' stabs.