[pacman-dev] [PATCH] makepkg: Include more source files in debug packages.

[Allan McRae]

On 26/2/20 11:00 am, Austin Lund wrote:
> On Mon, Feb 24, 2020 at 03:56:58PM +1000, Allan McRae wrote:
>> On 20/2/20 11:51 am, Austin Lund wrote:
>>> Currently only the file pointed to by the DW_AT_name is included as a source
>>> file in debug packages.  This means many files that are useful for debugging are
>>> not included.  For example, no header files are included but yet these may by
>>> referenced in the .debug_line section.
>>>
>>> This sed script converts into shell variables the debug dump information from
>>> readelf about compilation units, directory tables and file tables.  This can be
>>> used to get the full path of all the source files from within the package being
>>> compiled that are referenced in the debugging information.  Also, placeholder
>>> symbols (e.g. <builtin>) and paths outside the current source (e.g. linked
>>> libraries) will be more consistently ignored from inclusion in the debug
>>> packages.
>>>
>>> Signed-off-by: Austin Lund <austin.lund at gmail.com>
>>> ---
>>
>>
>> So...  that sed script is horrendous!  But let me see if I understand
>> this correctly.
>>
>>
>> We currently only look at the .debug_info section, finding
>> DW_AT_name/DW_AT_comp_dir pair to grab file names.  That appears to get
>> the main compilation units, but misses header files.  It looks like your
>> sed does something slightly different to get that info, although I can't
>> tell if there is a functional difference.
>>
>> Your patch additionally looks at the .debug_line section.  This section
>> has a table of directories that source files come from (which can be
>> filtered to remove system directories), and a file name table with files
>> from each directory.   This does not include the files we currently grab.
>>
>> But there must be something I am missing...  For the example of "ls" I
>> see "selinux.h" in from directory "./lib/selinux" in that .debug_line
>> output.   Your script does not include this file.  Using the rpmtool
>> "debugedit -l" does include that file in its file list.  There are quite
>> a few other examples.
>>
>> Am I on the right track?   Can you clarify what I am missing here?
> 
> It would seem I made a bad assmption about what was in and not in the current
> source tree.  There will be references to libc files that appear in the output
> as a relative path.  My thought was that if there wasn't a preceeding './' then
> it must refer to another directory.
> 
> Anyway, yes.  You are on the right track.  My hope was that you can install the
> debug package and get all available source listings.  Without these functions
> within the header files, that isn't possible.
> 
> What's a better approach to parsing the readelf output?  Awk?

Short answer...  I'm not sure of the best approach.  I'd just like it to
be readable.

I have file a bug:
https://bugs.archlinux.org/task/65677