[PATCH v4] ld: Add --encoded-package-metadata

[Jan Beulich]

On 23.07.2024 12:24, H.J. Lu wrote:
> On Tue, Jul 23, 2024, 6:19 PM Jan Beulich <jbeulich@suse.com> wrote:
> 
>> On 18.07.2024 11:04, Benjamin Drung wrote:
>>> Specifying the compiler flag `-Wl,--package-metadata=<JSON>` might not
>>> work, because the shells might eat the quotation marks and the compiler
>>> splits the JSON at the commas.
>>>
>>> Ubuntu tried to using a specs file to set `--package-metadata` but that
>>> turned out to be too fragile. autopkgtests might use the compiler flags
>>> but the needed environment variables are not set in the test
>>> environment. Debugging a crash of an application build with the -spec
>>> parameter lacks the environment variables. People like to iteratively
>>> continue building the software in the build directory while hacking on
>>> the package and then have no environment variable set.
>>>
>>> So introduce a `--encoded-package-metadata` linker flag that takes a
>>> percent-encoded JSON. Percent-encoding is used because it is a
>>> standard and simple to implement.
>>>
>>> Bug-Ubutru: https://bugs.launchpad.net/bugs/2071468
>>> Signed-off-by: Benjamin Drung <benjamin.drung@canonical.com>
>>
>> Okay. Please don't forget to add a reference to the PR that you created
>> upon H.J.'s request. I notice H.J. has voiced a readability concern
>> there, but I think that can be taken care of incrementally.
> 
> I think we should make the existing option
> usable instead of adding another option.

Can you at least vaguely explain how you envision doing so, without any
kind of risk of breaking existing uses?

Jan