[Bug backtrace/11908] New: Debugging PIE works with core dump, but not "live"

["devurandom at gmx dot net" <sourceware-bugzilla at sourceware dot org>]

I am on a ia64 Gentoo/Hardened machine, testing the PIE support of gdb 7.1
against a very simple program.
What I noticed is that gdb will successfully show the backtrace (including
symbols and code) when run against a coredump (gdb ./test ./test.core), but not
when working on the live executable (gdb ./test).
The problem will vanish when the executable is compiled with -nopie.

test.c, test, and test.core are attached.

Portage 2.2_rc67 (hardened/linux/ia64/10.0/server, gcc-4.4.4, glibc-2.11.2-r0,
2.6.32-hardened-r11 ia64)
=================================================================
System uname: Linux-2.6.32-hardened-r11-ia64-31-with-gentoo-2.0.1
Timestamp of tree: Sun, 08 Aug 2010 07:45:01 +0000
app-shells/bash:     4.0_p37
dev-lang/python:     2.6.4-r1, 3.1.2-r4
dev-util/cmake:      2.6.4-r3
sys-apps/baselayout: 2.0.1
sys-apps/openrc:     0.6.1-r1
sys-apps/sandbox:    2.2
sys-devel/autoconf:  2.65
sys-devel/automake:  1.10.3, 1.11.1
sys-devel/binutils:  2.20.1-r1
sys-devel/gcc:       4.4.4-r1
sys-devel/gcc-config: 1.4.1
sys-devel/libtool:   2.2.6b
virtual/os-headers:  2.6.30-r1
ACCEPT_KEYWORDS="ia64"
ACCEPT_LICENSE="* -@EULA"
CBUILD="ia64-unknown-linux-gnu"
CFLAGS="-pipe -mtune=mckinley -O2 -ftree-vectorize"
CHOST="ia64-unknown-linux-gnu"
CONFIG_PROTECT="/etc"
CONFIG_PROTECT_MASK="/etc/ca-certificates.conf /etc/env.d /etc/fonts/fonts.conf
/etc/gconf /etc/gentoo-release /etc/php/apache2-php5/ext-active/ /etc/php/cgi-
php5/ext-active/ /etc/php/cli-php5/ext-active/ /etc/revdep-rebuild
/etc/sandbox.d /etc/terminfo /etc/texmf/language.dat.d /etc/texmf/language.def.d
/etc/texmf/updmap.d /etc/texmf/web2c /etc/udev/rules.d"
CXXFLAGS="-pipe -mtune=mckinley -O2 -ftree-vectorize"
DISTDIR="/var/cache/portage/distfiles"
EMERGE_DEFAULT_OPTS="--with-bdeps y"
FEATURES="assume-digests distlocks fixpackages news parallel-fetch preserve-libs
protect-owned sandbox sfperms strict unmerge-logs unmerge-orphans userfetch
userpriv usersandbox usersync"
GENTOO_MIRRORS="http://ftp.spline.inf.fu-berlin.de/mirrors/gentoo/ http://ftp-
stud.fht-esslingen.de/pub/Mirrors/gentoo/ http://distfiles.gentoo.org";
LANG="en_GB.UTF-8"
LDFLAGS="-Wl,-O1 -Wl,--hash-style=gnu -Wl,--as-needed"
MAKEOPTS="-j3"
PKGDIR="/var/cache/portage/packages"
PORTAGE_COMPRESS="xz"
PORTAGE_CONFIGROOT="/"
[...]
PORTAGE_TMPDIR="/var/tmp"
PORTDIR="/var/cache/portage/gentoo"
PORTDIR_OVERLAY="/var/cache/portage/layman/sunrise /var/cache/portage/local"
[...]
Unset:  CPPFLAGS, CTARGET, FFLAGS, INSTALL_MASK, LC_ALL, LINGUAS,
PORTAGE_COMPRESS_FLAGS

-- 
           Summary: Debugging PIE works with core dump, but not "live"
           Product: gdb
           Version: 7.1
            Status: UNCONFIRMED
          Severity: minor
          Priority: P3
         Component: backtrace
        AssignedTo: unassigned at sourceware dot org
        ReportedBy: devurandom at gmx dot net
                CC: gdb-prs at sourceware dot org
  GCC host triplet: ia64-unknown-linux-gnu


http://sourceware.org/bugzilla/show_bug.cgi?id=11908

------- You are receiving this mail because: -------
You are on the CC list for the bug, or are watching someone who is.