[pacman-dev] Pacman split debug info symbol path

[Dave Reisner]

On Mar 29, 2014 1:36 PM, "Steven Noonan" <steven at uplinklabs.net> wrote:
>
> Hi folks,
>
> I think the directory Pacman is using for the split-out debug symbols
> is incorrect. This appears to be needed:

Why do you think this? What are the symptoms you're seeing? I use debug
packages all the time and they work as expected.

>
> commit 61ed104abf95ac38e7d317c760807f308ea90555
> Author: Steven Noonan <steven at uplinklabs.net>
> Date:   Wed Feb 12 05:44:16 2014 -0800
>
>     makepkg: use dash instead of underscore in /usr/lib/debug/.build-id
>
>     Signed-off-by: Steven Noonan <steven at uplinklabs.net>
>
> diff --git a/scripts/makepkg.sh.in b/scripts/makepkg.sh.in
> index 027fcc3..7e663af 100644
> --- a/scripts/makepkg.sh.in
> +++ b/scripts/makepkg.sh.in
> @@ -1525,7 +1525,7 @@ strip_file() {
>
>                 # has this file already been stripped
>                 if [[ -n "$bid" ]]; then
> -                       if [[ -f
> "$dbgdir/.build_id/${bid:0:2}/${bid:2}.debug" ]]; then
> +                       if [[ -f
> "$dbgdir/.build-id/${bid:0:2}/${bid:2}.debug" ]]; then
>                                 return
>                         fi
>                 elif [[ -f "$dbgdir/$binary.debug" ]]; then
> @@ -1546,15 +1546,15 @@ strip_file() {
>
>                 if [[ -n "$bid" ]]; then
>                         local target
> -                       mkdir -p "$dbgdir/.build_id/${bid:0:2}"
> +                       mkdir -p "$dbgdir/.build-id/${bid:0:2}"
>
>                         target="../../../../../${binary#./}"
>                         target="${target/..\/..\/usr\/lib\/}"
>                         target="${target/..\/usr\/}"
> -                       ln -s "$target"
"$dbgdir/.build_id/${bid:0:2}/${bid:2}"
> +                       ln -s "$target"
"$dbgdir/.build-id/${bid:0:2}/${bid:2}"
>
>                         target="../../${binary#./}.debug"
> -                       ln -s "$target"
> "$dbgdir/.build_id/${bid:0:2}/${bid:2}.debug"
> +                       ln -s "$target"
> "$dbgdir/.build-id/${bid:0:2}/${bid:2}.debug"
>                 fi
>         fi
>
> To justify this change, I can't find any tools that actually look in
> 'build_id' (with an underscore) when searching for symbols.
>
> For example, perf does this (lines 101, 105):
>
>
https://git.kernel.org/cgit/linux/kernel/git/stable/linux-stable.git/tree/tools/perf/util/build-id.c#n92
>
> GDB also looks in '.build-id' (lines 83, 102):
>
>
https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=blob;f=gdb/build-id.c;h=491900b3e545c72325a54fc79847b8872fa63aae;hb=HEAD#l73
>
> OProfile, same issue (lines 93, 104):
>
>
http://sourceforge.net/p/oprofile/oprofile/ci/master/tree/libutil++/bfd_support.cpp
>
> I noticed tool breakage back when I submitted the kernel module
> split+debug patch, but kept the patch to myself because I figured I
> must have been missing the rationale for the difference, but I've been
> so far unable to find any.
>
> - Steven
>