A @code{N_SLINE} symbol represents the start of a source line. The
@var{desc} field contains the line number and the @var{value} field
-contains the code address for the start of that source line.
+contains the code address for the start of that source line. On most
+machines the address is absolute; for Sun's stabs-in-elf, it is relative
+to the function in which the @code{N_SLINE} symbol occurs.
GNU documents @code{N_DSLINE} and @code{N_BSLINE} symbols for line
numbers in the data or bss segments, respectively. They are identical
@node Block Structure
@section Block Structure
-@table @strong
-@item Directive:
-@code{.stabn}
-@item Types:
-@code{N_LBRAC}, @code{N_RBRAC}
-@end table
-
The program's block structure is represented by the @code{N_LBRAC} (left
-brace) and the @code{N_RBRAC} (right brace) stab types. The following code
-range, which is the body of @code{main}, is labeled with @samp{LBB2:} at the
-beginning and @samp{LBE2:} at the end.
-
-@example
-37 LBB2:
-38 sethi %hi(LC0),%o1
-39 or %o1,%lo(LC0),%o0
-40 call _printf,0
-41 nop
-42 .stabn 68,0,6,LM3
-43 LM3:
-44 LBE2:
-@end example
+brace) and the @code{N_RBRAC} (right brace) stab types. The variables
+defined inside a block preceded the @code{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
+@code{N_LBRAC} symbol. The values of the @code{N_LBRAC} and
+@code{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 Sun's stabs-in-elf, they are relative to the function in
+which they occur.
The @code{N_LBRAC} and @code{N_RBRAC} stabs that describe the block
-scope of the procedure are located after the @code{N_FUNC} stab that
-represents the procedure itself. The @code{N_LBRAC} uses the
-@code{LBB2} label as the code address in its value field, and the
-@code{N_RBRAC} uses @code{LBE2}.
-
-@example
-50 .stabs "main:F1",36,0,0,_main
-@end example
-
-@example
- .stabn N_LBRAC, NIL, NIL, @var{left-brace-address}
- .stabn N_RBRAC, NIL, NIL, @var{right-brace-address}
-@end example
+scope of a procedure are located after the @code{N_FUN} stab that
+represents the procedure itself.
-@example
-51 .stabn 192,0,0,LBB2
-52 .stabn 224,0,0,LBE2
-@end example
+Sun documents the @code{desc} field of @code{N_LBRAC} and
+@code{N_RBRAC} symbols as containing the nesting level of the block.
+However, dbx seems not to care, and GCC just always set @code{desc} to
+zero.
@node Constants
@chapter Constants
Beginning of an include file (Sun only), @xref{Source Files}.
@item 0x84 N_SOL
-Name of sub-source (#include) file., @xref{Source Files}.
+Name of include file, @xref{Source Files}.
@item 0xa0 N_PSYM
Parameter variable, @xref{Parameters}.
Alternate entry point, @xref{N_ENTRY}.
@item 0xc0 N_LBRAC
-Beginning of a lexical block, @xref{N_LBRAC}.
+Beginning of a lexical block, @xref{Block Structure}.
@item 0xc2 N_EXCL
Place holder for a deleted include file, @xref{Source Files}.
Modula2 scope information (Sun linker), @xref{N_SCOPE}.
@item 0xe0 N_RBRAC
-End of a lexical block, @xref{N_RBRAC}.
+End of a lexical block, @xref{Block Structure}.
@item 0xe2 N_BCOMM
Begin named common block, @xref{N_BCOMM}.
* N_SSYM:: Structure or union element
* N_LSYM:: Automatic variable
* N_ENTRY:: Alternate entry point
-* N_LBRAC:: Beginning of lexical block
* N_SCOPE:: Modula2 scope information (Sun only)
-* N_RBRAC:: End of lexical block
* N_BCOMM:: Begin named common block
* N_ECOMM:: End named common block
* N_ECOML:: End common
Value is its address.
<<?>>
-@node N_LBRAC
-@section 192 - 0xc0 - N_LBRAC
-
-Beginning of a lexical block (left brace). The variable defined
-inside the block precede the N_LBRAC symbol. Or can they follow as
-well as long as a new N_FUNC was not encountered. <<?>>
-
-@display
-.stabn N_LBRAC, NIL, NIL, value
-@end display
-
-@example
-value -> code address of block start.
-@end example
-
@node N_SCOPE
@section 196 - 0xc4 - N_SCOPE
Modula2 scope information (Sun linker)
<<?>>
-@node N_RBRAC
-@section 224 - 0xe0 - N_RBRAC
-
-End of a lexical block (right brace)
-
-@display
-.stabn N_RBRAC, NIL, NIL, value
-@end display
-
-@example
-value -> code address of the end of the block.
-@end example
-
@node N_BCOMM
@section 226 - 0xe2 - N_BCOMM
GNU C stabs define *all* types, file or procedure scope, as
N_LSYM. Sun doc talks about using N_GSYM too.
-@item
-Stabs describing block scopes, N_LBRAC and N_RBRAC are supposed to
-contain the nesting level of the block in the desc field, re Sun doc.
-GNU stabs always have 0 in that field. dbx seems not to care.
-
@item
Sun C stabs use type number pairs in the format (a,b) where a is a
number starting with 1 and incremented for each sub-source file in the
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