Address review comments.

In D17015#363060, @kossebau wrote:

Good to see you caring for ECM documentation not getting broken with Qt 5.12 :)

Any idea how we could perhaps deduplicate the FindQHelpGenerator.cmake with the one from find-modules (which is a helper for runtime with the ECMAddQch macro)? No instant idea yet, perhaps also better to have dedicated variants for each purppse? Needs me another round of thinking.

Add the reason for looking for the executable

ping?

A more complete draft:

You will notice that I plan to maintain an option to disable the Apple-specific behaviour for anyone who depends on the current behaviour (that includes me, but your script would also continue to work). Cf. the APPLE_FORCE_X11 option

Can we set DATAROOTDIR=/Library/Application Support/KDE so that everything remains nicely bundled?

Good to see you caring for ECM documentation not getting broken with Qt 5.12 :)

Done. kfilemetadata was also changed to use FindLibExiv2.cmake.

Looks good to me.

Wow...

If anyone wonders:

This implements and uses my idea of an ecm_add_<lang>_compiler_flags_if_supported function set for C and C++. It uses compiler ID+version conditions to determine if flag(s) are supported when those conditions are known and reliable - otherwise and only then does it resort to querying the compiler.

Good find. No idea why it was not like this from the start.

Looks ok to me, less stuff to set manually is always good.

Something side-ways related: I went down this hole because cmake's generate_export_header failed because of an unsupported flag that was added.
Regardless of how we implement things here, shouldn't there be something like ecm_generate_export_header which empties CMAKE_CXX_FLAGS temporarily because calling CMake's version and then restores the variable? There's no feedback at all in this function, the generated export header just contains dummy EXPORT macros, leaving the user to wonder why the linker fails. Or should the visibility flags also be set conditionally, after setting all other compiler options?

Thus these places need to be turned into:

  ...
  if(CMAKE_CXX_COMPILER_ID STREQUAL "Clang" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS "3.8")
  elseif(CMAKE_CXX_COMPILER_ID STREQUAL "AppleClang" AND CMAKE_CXX_COMPILER_VERSION VERSION_LESS "8.1.0")

I don't like the hiding of the if-branches as argument to macro. We shouldn't to this as it makes the code harder to understand.

A simpler version, setting CMAKE_<LANG>_FLAGS directly (also fixes a persistence error in my previous implementation).

Don't worry, the commit message would have looked like that.
Or rather, it will say

Don't worry, the commit message would have looked like that.

The commit message is wrong. It should be Use STREQUAL "Clang" to detect the clang for compatibility with Apple systems.

If there are no further comments, I will push this on sunday.

In D15070#347945, @cgiboudeaux wrote:

In D15070#347944, @bruns wrote:

So, after another week, no reason has been given not to accept this.

1. It fixes broken behavior on several platforms
2. It does not break current setups
3. It is consistent with other config variables

That's not true, you're refusing to fix the issues. Why should we invest time reviewing your changes, exactly?

In D15070#347944, @bruns wrote:

So, after another week, no reason has been given not to accept this.

1. It fixes broken behavior on several platforms
2. It does not break current setups
3. It is consistent with other config variables

So, after another week, no reason has been given not to accept this.

In D15070#345218, @cgiboudeaux wrote:

In D15070#344900, @bruns wrote:

In D15070#344884, @cgiboudeaux wrote:

In D15070#344871, @bruns wrote:

As all the raised concerns have been dealed with, can we give this a try while the next KF release is still somewhat in the future?

No, the empty if must be removed. Code that does nothing is useless.

Its not empty, there is a comment inside. Of course I can add a set(KDE_INSTALL_PYTHON${pyversion}DIR ${KDE_INSTALL_PYTHON${pyversion}DIR}) if you insist ...

And if you restructure it you either end up with a lengthy if condition - if (NOT KDE_INSTALL_PYTHON${pyversion}DIR AND KDE_INSTALL_USE_PYTHON${pyversion}_SYS_PATHS) - or another nesting level. Both are significantly harder to read.

If KDE_INSTALL_USE_PYTHON${pyversion}_SYS_PATHS is true, KDE_INSTALL_PYTHON${pyversion}DIR can be ignored. This was in the review

In D15070#344900, @bruns wrote:

In D15070#344884, @cgiboudeaux wrote:

In D15070#344871, @bruns wrote:

As all the raised concerns have been dealed with, can we give this a try while the next KF release is still somewhat in the future?

No, the empty if must be removed. Code that does nothing is useless.

Its not empty, there is a comment inside. Of course I can add a set(KDE_INSTALL_PYTHON${pyversion}DIR ${KDE_INSTALL_PYTHON${pyversion}DIR}) if you insist ...

And if you restructure it you either end up with a lengthy if condition - if (NOT KDE_INSTALL_PYTHON${pyversion}DIR AND KDE_INSTALL_USE_PYTHON${pyversion}_SYS_PATHS) - or another nesting level. Both are significantly harder to read.

In D15070#344884, @cgiboudeaux wrote:

In D15070#344871, @bruns wrote:

As all the raised concerns have been dealed with, can we give this a try while the next KF release is still somewhat in the future?

No, the empty if must be removed. Code that does nothing is useless.

In D15070#344871, @bruns wrote:

As all the raised concerns have been dealed with, can we give this a try while the next KF release is still somewhat in the future?

As all the raised concerns have been dealed with, can we give this a try while the next KF release is still somewhat in the future?

sorry, busy with other stuff

Looks OK to me.

This is a trivial cleanup - can I push it?

Add documentation, remove leftover GPB_PYTHON${pyversion}_SITEARCH

Update summary/test plan

Thanks to arc for throwing my commit message away ...

Use same pattern as KDE_INSTALL_USE_QT_SYS_PATHS

Confirmed to work with PyQt 5.10.1 and Qt 5.11.1

rebase

works fine, sorry for the doubt, I probably badly applied it last time.

Rebased

Are you sure you applied the patch properly? You are getting the warning that we are guarding against.

Ping?