CMake netsockets: too many libraries dependencies

[0xc0170]

Description of defect

Build mbed-os-example-sockets with mbedtools (CMake) and check what files are being included. While we were looking at object libraries, we found these dependencies for netsockets:

target_link_libraries(mbed-netsocket
    PRIVATE
        mbed-nanostack
        mbed-randlib
        mbed-core
        mbed-rtos
        mbed-lwipstack
        mbed-nanostack-libservice
        mbed-ppp
    PUBLIC
        mbed-events
        mbed-mbedtls
)

Note, the above comes from feature-cmake-object-libraries branch. It is not that obvious if you use master due to INTERFACE libraries and how they are all linked together. You can however confirm these deps with an application to see what it pulls in.

This is also related to #14412 (not certain if we clean up randlib, we would remove nanostack dependency for netsockets, we should review if we need mbed-nanostack-libservice and mbed-ppp always. Questionable would be also mbedtls events as they are required only for secure sockets, or anything else in the tree?

The other part is because events and tls are used in the public headers (basically they are leaked to anyone using netsockets), this mean anyone linking to netsockets will also need to get events/tls linked (see PUBLIC linking above). But this might be more related to mbed.h as it provides all by default.

Target(s) affected by this defect ?

all

Toolchain(s) (name and version) displaying this defect ?

all

What version of Mbed-os are you using (tag or sha) ?

mbed-os-6.8

What version(s) of tools are you using. List all that apply (E.g. mbed-cli)

mbedt-tools 7.0

How is this defect reproduced ?

Build mbed-os-exaple-socket and explore build.ninja file what is include (number of files is a good indicator as well how much we are including for this example).

[ciarmcom]

Thank you for raising this detailed GitHub issue. I am now notifying our internal issue triagers.
Internal Jira reference: https://jira.arm.com/browse/IOTOSM-3576

[boraozgen]

Compiling 800+ files for an ethernet based socket example. Not much of an improvement on the old tools in this case :)

[0xc0170]

Compiling 800+ files for an ethernet based socket example. Not much of an improvement on the old tools in this case :)

Correct. I created these issues about deps so we can plan this work - most of us are not aware of them as old tool hide this detail. It's not trivial as it was just easy to add a header here, there - building tree with "all in" for years.

It will require to go through the libraries and remove deps where they can.

[ladislas]

Just hit this issue, compilation times are way to long because of this.

[ladislas]

Correct. I created these issues about deps so we can plan this work

@0xc0170 any ideas when things like this will be worked on? It seems like the CMake migration, though promising, has been lost in translation.

[0xc0170]

Unfortunately, we haven't been able to continue the migration.
The teams are much smaller as the previous years, we are currently coping with other priorities.