Re: [RFA] New dwarf2_attribute_true_p function in dwarf2read.c

Daniel Jacobowitz
2004-04-16T14:20:29Z

On Thu, Apr 15, 2004 at 01:23:18PM -0700, Joel Brobecker wrote:
> Hello,
>
> Following a suggestion made by JimB in:
>
> http://sources.redhat.com/ml/gdb-patches/2004-04/msg00297.html
>
> I made the following change:
>
> 2004-04-15 Joel Brobecker <brobecker@gnat.com>
>
> * dwarf2read.c (dwarf2_attribute_true_p): New function.
> (die_is_declaration): Use the function above.
>
> Tested on x86-linux, no regression.
>
> OK to apply?

Sorry, this patch is incorrect.

> - return (dwarf2_attr (die, DW_AT_declaration, cu)
> - && ! dwarf2_attr (die, DW_AT_specification, cu));
> + /* A DIE is a declaration if it has a DW_AT_declaration attribute
> + which value is non-zero. However, we have to be careful of DIEs
> + with a DW_AT_specification attribute, because dwarf2_attribute_p()
> + follows this attribute, and therefore might cause us to find a
> + DW_AT_declaration attribute, but that belongs to a different DIE. */
> + return (dwarf2_attribute_true_p (die, DW_AT_declaration, cu)
> + && ! dwarf2_attribute_true_p (die, DW_AT_specification, cu));
> }
>
> /* Return the die giving the specification for DIE, if there is

First of all, there's no dwarf2_attribute_p, you mean dwarf2_attr and
dwarf2_attr_true_p.

Secondly, the predicate function should be used for flag attributes
like DW_AT_declaration, but checking DW_UNSND for DW_AT_specification
is incorrect - it's a DIE reference. dwarf2_attr != NULL is the right
check. Some day I hope to add checking macros to verify we're using
the right member of each union...

--
Daniel Jacobowitz
MontaVista Software Debian GNU/Linux Developer