Re: [PATCH 1/1] Enhancements to allow core file debugging to work properly from devices

[Mark Hatle <mark.hatle@windriver.com>]

On 10/31/13, 1:54 AM, blloyd wrote:
> gdb includes a script to make generating core files trivial.  Add a package to allow inclusion of this script in images.  GDB also requires symbols that are usually stripped from the threads library to properly generate a core dump.  Therefore, ensure when gdb is installed the necessary debug file is also present so gdb is fully functional.
>
> Signed-off-by: blloyd <blloyd@familyhonor.net>
> ---
>   meta/recipes-devtools/gdb/gdb-common.inc | 12 +++++++-----
>   meta/recipes-devtools/gdb/gdb.inc        |  9 ++++++++-
>   2 files changed, 15 insertions(+), 6 deletions(-)
>
> diff --git a/meta/recipes-devtools/gdb/gdb-common.inc b/meta/recipes-devtools/gdb/gdb-common.inc
> index 6954954..02eef85 100644
> --- a/meta/recipes-devtools/gdb/gdb-common.inc
> +++ b/meta/recipes-devtools/gdb/gdb-common.inc
> @@ -61,8 +61,10 @@ do_install_append() {
>   	rm -rf ${D}${datadir}/locale
>   }
>
> -RRECOMMENDS_gdb_append_linux = " glibc-thread-db "
> -RRECOMMENDS_gdb_append_linux-gnueabi = " glibc-thread-db "
> -RRECOMMENDS_gdbserver_append_linux = " glibc-thread-db "
> -RRECOMMENDS_gdbserver_append_linux-gnueabi = " glibc-thread-db "
> -
> +# Unfortunately, for gdb multi-threading to function reliably it must have the eglibc debug symbols
> +# which are a part of the eglibc-dev package.  So we have added a dependency on that here.
> +RRECOMMENDS_gdb_append_linux = " glibc-thread-db eglibc-dev "
> +RRECOMMENDS_gdb_append_linux-gnueabi = " glibc-thread-db eglibc-dev "
> +RRECOMMENDS_gdbserver_append_linux = " glibc-thread-db eglibc-dev "
> +RRECOMMENDS_gdbserver_append_linux-gnueabi = " glibc-thread-db eglibc-dev "
> +RDEPENDS_gcore_append = " gdb "

The debug symbols should be in the -dbg package, not the -dev package.  The -dev 
package should simply be symlinks and special development only components, while 
the -dbg is the split symbols.

With the eglibc-dbg installed onto the gdb environment, it should be possible to 
have all necessary symbols to do whatever processing is required.  If this 
doesn't work, it likely needs to be investigated.  (If something in -dev is 
required, likely there is another bug somewhere else that needs to be fixed in 
the packaging of eglibc.)

Do you have steps on using this code (a test command perhaps?).  I've recently 
been asked to investigate some issues with debugging when using libpthread, and 
I suspect the problem may be over zealous stripping of the libpthread.so on the 
target.  But I still haven't finished my evaluation yet.

--Mark

> diff --git a/meta/recipes-devtools/gdb/gdb.inc b/meta/recipes-devtools/gdb/gdb.inc
> index 3321a24..9bf0e86 100644
> --- a/meta/recipes-devtools/gdb/gdb.inc
> +++ b/meta/recipes-devtools/gdb/gdb.inc
> @@ -10,5 +10,12 @@ SRC_URI += "file://kill_arm_map_symbols.patch \
>   #export CFLAGS_append=" -L${STAGING_LIBDIR}"
>
>   # cross-canadian must not see this
> -PACKAGES =+ "gdbserver"
> +PACKAGES =+ "gdbserver gcore"
>   FILES_gdbserver = "${bindir}/gdbserver"
> +FILES_gcore = "${bindir}/gcore"
> +
> +do_install_append() {
> +  # When trying to find what went wrong with a program, a core dump can be very helpful
> +  # Go ahead and make it easier to get one when we have gdb on the system
> +  install -m 0755 ${S}/gdb/gdb_gcore.sh ${D}${bindir}/gcore
> +}
>