clang's variadic macro warnings: only for clang

[yopito]

following settings of cmake/modules/Warnings.cmake

once applied, no more zillon of warning on building as below:

cc1plus: note: unrecognized command-line option '-Wno-gnu-zero-variadic-macro-arguments' may have been intended to silence earlier diagnostics

Edit: appeared on 3.1.3 or 3.2 release

[FlexW]

Thanks. Could you do it in a little bit different way, so that the flags get not set globally. Paste this

# Calling Qt's qCWarning(category, ...) with no params for "..." is a GNU
# extension (C++11 §16.3/4 forbids them). Silence clang's warnings.
target_compile_options("${csync_NAME}" PUBLIC
  $<$<CXX_COMPILER_ID:Clang>:-Wno-gnu-zero-variadic-macro-arguments>
  $<$<C_COMPILER_ID:Clang>:-Wno-gnu-zero-variadic-macro-arguments>)

right below add_library("${csync_NAME}" ...) in src/csync/CMakeLists.txt.

Then remove

  # Calling Qt's qCWarning(category, ...) with no params for "..." is a GNU
  # extension (C++11 §16.3/4 forbids them). Silence clang's warnings.
  set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} -Wno-gnu-zero-variadic-macro-arguments")
  set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-gnu-zero-variadic-macro-arguments")

entirely from src/CMakeLists.txt.

Additionally it would be great if you can signoff your commit to please the DCO bot.

[FlexW]

See my comment

[yopito]

hello @FlexW : thanks for your inputs.
I don't feel confident to apply your changes: I don't understand them, not fluent enough in cmake.
Would you patch it on you own (PR) ?

[FlexW]

@yopito Yes, I can do it. But thinking a bit more about this, I'm not sure anymore if that is the best way to solve the problem. I have the feeling that setting this warning should be a private property and not automatically should change the flags on all targets that link to the csync target. However, if making it private, we need to set it on each target separate. @mgallien What do you think?

[er-vin]

By the way, would that be more appropriate to do that in master and backport? So far the project followed a backport strategy not a forward port one.

[FlexW]

By the way, would that be more appropriate to do that in master and backport? So far the project followed a backport strategy not a forward port one.

Of course that would be better :) Thanks for hinting it.

[yopito]

OK, I've reworked this PR against master branch.
Have to "signoff commit to please the DCO bot"

[FlexW]

Thank you. I'll will merge that now as it is.

[FlexW]

/rebase

[nextcloud-desktop-bot]

AppImage file: Nextcloud-PR-3132-14d61c507157cc0c45201f934255c6dde03f64fc-x86_64.AppImage

To test this change/fix you can simply download above AppImage file and test it.

Please make sure to quit your existing Nextcloud app and backup your data.