public inbox for systemtap@sourceware.org
 help / color / mirror / Atom feed
From: "wcohen at redhat dot com" <sourceware-bugzilla@sourceware.org>
To: systemtap@sourceware.org
Subject: [Bug translator/29037] Systemtap unable to find struct bitfield members for gcc11 compiled code
Date: Thu, 07 Apr 2022 14:30:16 +0000	[thread overview]
Message-ID: <bug-29037-6586-CAW5hqef1Y@http.sourceware.org/bugzilla/> (raw)
In-Reply-To: <bug-29037-6586@http.sourceware.org/bugzilla/>

https://sourceware.org/bugzilla/show_bug.cgi?id=29037

--- Comment #1 from William Cohen <wcohen at redhat dot com> ---
There are some differences in member information for the field.  In the dwarf
for RHEL8 see:

0x000002f8:   DW_TAG_structure_type
                DW_AT_name      ("fields")
                DW_AT_byte_size (0x01)
                DW_AT_decl_file ("/home/wcohen/fields.c")
                DW_AT_decl_line (6)
                DW_AT_decl_column       (0x08)
                DW_AT_sibling   (0x00000346)

0x00000305:     DW_TAG_member
                  DW_AT_name    ("icsk_ca_state")
                  DW_AT_decl_file       ("/home/wcohen/fields.c")
                  DW_AT_decl_line       (7)
                  DW_AT_decl_column     (0x0a)
                  DW_AT_type    (0x000002ec "__u8")
                  DW_AT_byte_size       (0x01)
                  DW_AT_bit_size        (0x05)
                  DW_AT_bit_offset      (0x03)
                  DW_AT_data_member_location    (0x00)


For Rawhide there is no DW_AT_data_member_location:

0x00000088:   DW_TAG_structure_type
                DW_AT_name      ("fields")
                DW_AT_byte_size (0x01)
                DW_AT_decl_file ("/home/wcohen/fields.c")
                DW_AT_decl_line (6)
                DW_AT_decl_column       (0x08)
                DW_AT_sibling   (0x000000ca)

0x00000095:     DW_TAG_member
                  DW_AT_name    ("icsk_ca_state")
                  DW_AT_decl_file       ("/home/wcohen/fields.c")
                  DW_AT_decl_line       (7)
                  DW_AT_decl_column     (0x0a)
                  DW_AT_type    (0x0000007c "__u8")
                  DW_AT_bit_size        (0x05)
                  DW_AT_data_bit_offset (0x00)

dwflpp.cxx:3470 has a check on DW_AT_data_member_location and only adds things
if there a DW_AT_data_member_location.  According to DWARF5.pdf
DW_AT_data_bit_offset would also be valid:

The member entry corresponding to a data member that is defined in a structure,
union or class may have either a DW_AT_data_member_location attribute or a
DW_AT_data_bit_offset attribute. If the beginning of the data member is the
same as the beginning of the containing entity then neither attribute is
required.

-- 
You are receiving this mail because:
You are the assignee for the bug.

  reply	other threads:[~2022-04-07 14:30 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-04-07 14:10 [Bug translator/29037] New: " wcohen at redhat dot com
2022-04-07 14:30 ` wcohen at redhat dot com [this message]
2022-04-21 22:03 ` [Bug translator/29037] " wcohen at redhat dot com
2022-06-15 14:00 ` wcohen at redhat dot com
2022-06-24 21:31 ` wcohen at redhat dot com
2022-07-01 17:39 ` wcohen at redhat dot com
2022-07-08 17:36 ` wcohen at redhat dot com
2023-03-09 22:09 ` fche at redhat dot com

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=bug-29037-6586-CAW5hqef1Y@http.sourceware.org/bugzilla/ \
    --to=sourceware-bugzilla@sourceware.org \
    --cc=systemtap@sourceware.org \
    /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).