From: Jan Kratochvil <jan.kratochvil@redhat.com>
To: archer@sourceware.org
Cc: Sami Wagiaalla <swagiaal@redhat.com>, Keith Seitz <keiths@redhat.com>
Subject: Re: Cross-CU C++ DIE references vs. mangling
Date: Wed, 10 Mar 2010 19:32:00 -0000 [thread overview]
Message-ID: <20100310193207.GA6147@host0.dyn.jankratochvil.net> (raw)
In-Reply-To: <20100310191833.GA2816@host0.dyn.jankratochvil.net>
On Wed, 10 Mar 2010 20:18:33 +0100, Jan Kratochvil wrote:
> So GDB has to know the "S::i"->"_ZN1S1iE" mangling rules if there would be no
> DW_AT_MIPS_linkage_name. Just in this case GDB will find out "S::i" in the
> defining CU (or shared library) and it can completely ignore this declaration.
...
> So there is a countercase where GDB cannot ignore such declaration-only DIE
> (and it is AFAIK the only requirement for GDB internal LOC_UNRESOLVED type):
> namespace S
> {
> int f ()
> {
> int i = 42;
> {
> extern int i;
> return i;
> }
> }
> }
...
> <4><92>: Abbrev Number: 9 (DW_TAG_lexical_block)
> <93> DW_AT_low_pc : 0xb
> <9b> DW_AT_high_pc : 0x11
> <2><45>: Abbrev Number: 4 (DW_TAG_variable)
> <46> DW_AT_name : i
> <4a> DW_AT_MIPS_linkage_name: (indirect string, offset: 0x40): _ZN1S1iE
> <52> DW_AT_external : 1
> <53> DW_AT_declaration : 1
In this case if it see DW_AT_external + DW_AT_declaration it can also global
"S::i" defining DIE so DW_AT_MIPS_linkage_name is probably really not needed.
Found it only after posting it, sorry,
Jan
next prev parent reply other threads:[~2010-03-10 19:32 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-03-10 19:18 Jan Kratochvil
2010-03-10 19:32 ` Jan Kratochvil [this message]
2010-03-11 6:03 ` Roland McGrath
2010-04-12 18:51 ` Sami Wagiaalla
2010-04-27 8:50 ` Roland McGrath
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20100310193207.GA6147@host0.dyn.jankratochvil.net \
--to=jan.kratochvil@redhat.com \
--cc=archer@sourceware.org \
--cc=keiths@redhat.com \
--cc=swagiaal@redhat.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).