Re: gdb/1465

[David Carlton <carlton at kealia dot com>]

The following reply was made to PR c++/1465; it has been noted by GNATS.

From: David Carlton <carlton@kealia.com>
To: mec.gnu@mindspring.com (Michael Elizabeth Chastain)
Cc: gdb-gnats@sources.redhat.com
Subject: Re: gdb/1465
Date: Wed, 26 Nov 2003 13:20:16 -0800

 On Wed, 26 Nov 2003 16:09:08 -0500 (EST), mec.gnu@mindspring.com (Michael Elizabeth Chastain) said:
 
 > gnuv2_value_rtti_type wants to find the rtti type for the static type "A".
 > So it calls lookup_typename.
 
 > The objfile for the main executable has one symtab.
 > This symtab has a static block, as usual.
 > This static block has the symbol for "struct A".
 >   I want to find this symbol.
 
 Right.  But, as I just e-mailed in a separate thread, I think this is
 part of the problem here - this symbol shouldn't be in a static block,
 it should be in a global block.  And my latest patch awaiting
 approval, among other things, puts it in a global block.
 
 > I think the real problem is the point where gnuv2_value_rtti_type
 > specifies block=0.  Conceptually, that looks wrong to me.  gdb is
 > looking up a type name and the type name might have different
 > meanings in different scopes.  lookup_typename really needs a
 > correct block argument.
 
 Yes, I agree.
 
 > The problem is: there is no handy block pointer lying around in
 > gnuv2_value_rtti_type, or anywhere in the call stack above it, for
 > that matter.  Can someone help me out here?
 
 There's always get_selected_block (0), or whatever it's called.  But
 I'm not sure that that will always be the correct thing to do.
 
 > Another question: v2 searches in VAR_DOMAIN, and v3 searches in
 > STRUCT_DOMAIN.  Why the difference?
 
 Beats me.  I think VAR_DOMAIN is better.
 
 > (1) Change gnuv2_value_rtti_type from lookup_typename to
 >     lookup_symbol.
 
 Yeah.  After all, the only difference is that lookup_typename has the
 primitive type stuff, but that shouldn't come into play for RTTI
 information.
 
 David Carlton
 carlton@kealia.com