Mirror of the gdb-patches mailing list
 help / color / mirror / Atom feed
From: Daniel Jacobowitz <drow@false.org>
To: Christophe LYON <christophe.lyon@st.com>
Cc: Joel Brobecker <brobecker@adacore.com>, gdb-patches@sources.redhat.com
Subject: Re: [PATCH] obvious pattern fix in gdb.base/step-line.exp
Date: Fri, 17 Apr 2009 17:30:00 -0000	[thread overview]
Message-ID: <20090417173031.GA13377@caradoc.them.org> (raw)
In-Reply-To: <49E8B701.1000402@st.com>

On Fri, Apr 17, 2009 at 07:06:09PM +0200, Christophe LYON wrote:
> However, from GDB, using "maintenance print symbols", I noticed that  
> quite a few lines have become "0" instead of meaningful values. In turn,  
> I thinks this makes skip_prologue do something wrong.
>
> What I dont' understand currently is where those "0" line entries come  
> from? Is there any verbose flag or maintenance command I could use to  
> understand how the Dwarf debug_line info is parsed?

Not really, but it's pretty straightforward to step through.

GDB uses line 0 internally to represent a lack of line number
information.  This is required because the line table uses
half-ranges; a line number and a start address.  We get a line
0 at file switch events or at DW_LNS_end_of_sequence.  There's
some hairy bits to make sure the 0 appears 'before' any other line
marker at the same address.

-- 
Daniel Jacobowitz
CodeSourcery


      reply	other threads:[~2009-04-17 17:30 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2009-03-27 14:05 Christophe LYON
2009-03-27 18:53 ` Joel Brobecker
2009-03-30 13:51   ` Christophe LYON
2009-03-30 18:23     ` Joel Brobecker
2009-03-31 15:25       ` Christophe LYON
2009-04-01 18:32         ` Joel Brobecker
2009-04-02  8:52           ` Christophe LYON
2009-04-17 17:07             ` Christophe LYON
2009-04-17 17:30               ` Daniel Jacobowitz [this message]

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=20090417173031.GA13377@caradoc.them.org \
    --to=drow@false.org \
    --cc=brobecker@adacore.com \
    --cc=christophe.lyon@st.com \
    --cc=gdb-patches@sources.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