Re: stabs and #define/#undef

[Ian Lance Taylor <iant at google dot com>]

David Taylor <dtaylor@emc.com> writes:

> 2006-10-06  David Taylor  <dtaylor@emc.com>
> 
> 	* c-lex.c (init_c_lex):  Set debug callbacks for DBX_DEBUG also,
> 	as it's now implemented.
> 	* dbxout.c (dbxout_define, dbxout_undef):  New functions.
> 	(dbx_debug_hooks):  Add initializations for dbxout_define and
> 	dbxout_undef.
> 	* stab.def (N_MAC_DEFINE, N_MAC_UNDEF):  Define.

This patch is OK for mainline with a couple of changes, but check with
the gdb developers first as noted below.

(Technically I can't approve the change to c-lex.c, but it's only one
line, and I think it counts as obvious once the rest of the patch is
in).

> +/* Called from debug_define in toplev.c.  The `buffer' parameter contains
> +   the tail part of the directive line, i.e. the part which is past the
> +   initial whitespace, #, whitespace, directive-name, whitespace part.  */

The first sentence in this comment is wrong.  Just remove it.

> +/* Called from debug_undef in toplev.c.  The `buffer' parameter contains
> +   the tail part of the directive line, i.e. the part which is past the
> +   initial whitespace, #, whitespace, directive-name, whitespace part.  */

Same here.

> Index: gcc/stab.def
> ===================================================================
> --- gcc/stab.def	(revision 117374)
> +++ gcc/stab.def	(working copy)
> @@ -59,10 +59,16 @@
>  /* "No DST map for sym: name, ,0,type,ignored"  according to Ultrix V4.0.  */
>  __define_stab (N_NOMAP, 0x34, "NOMAP")
>  
> +/* GNU extension.  Macro define.  */
> +__define_stab(N_MAC_DEFINE, 0x36, "MAC_DEFINE")
> +
>  /* New stab from Solaris.  I don't know what it means, but it
>     don't seem to contain useful information.  */
>  __define_stab (N_OBJ, 0x38, "OBJ")
>  
> +/* GNU extension.  Macro undefine.  */
> +__define_stab(N_MAC_UNDEF, 0x3a, "MAC_UNDEF")
> +

You need to also update the matrix format starting at line 190.

Patch is OK for gcc with those changes.

Please send a patch to the gdb folks for gdb/doc/stabs.texinfo.  In
fact, please do that before you check the change into gcc, in case
they have any recommend changes.

Thanks.

Ian