qt5base-lts/coin/instructions/qmake_examples
Alexandru Croitor 440438092b coin: Use configure and qt-configure-module in instructions
We want to use configure and qt-configure-module when building in
Coin, rather than pure cmake and qt-cmake.

There are a few benefits:
- CI tests the scripts, making sure we don't introduce regressions
- CI uses the same scripts that we mention in our documentation for
developers to use
- The platform configurations become a bit less verbose and easier to
read due to less shouty-case CMake options

To ensure a more gradual porting, Coin will only use the new
instructions if the 'UseConfigure' feature is set on a platform
configuration in qt5.git. This allows going back to the old
instructions in case if something isn't working properly.

Due the opt-in, we need to support both old and new instructions in
the implementation.

The change strives to remove as much duplicate code as possible,
by moving it into common includes.

The README.md is updated to mention the overview of how the different
environment variables are used.

There are a few important things to point out.

1) Because during the porting we have to allow mixing of the old style
and new style, platform configs have to separate CMake-style options
from configure-style options in different environment variables.
Otherwise the instructions wouldn't be able to create a valid
configure call, where all CMake-style options have to go at the end
after a double dash --.

After all platform configs are ported to the new style, it should be
possible to combine all the options in a single environment variable
if that is desired, but it will require another round of porting to
remove all the '-D' prefixes in CMake-style options, and just use
regular variable assignment which configure supports.
e.g. -DQT_BUILD_EXAMPLES=ON becomes QT_BUILD_EXAMPLES=ON, which can be
mixed in-between configure-style args.

2) Configure is more strict in that it doesn't allow passing
unknown options. Due to that, we can't pass non-qtbase configure
options via NON_QTBASE_CONFIGURE_ARGS. qt-configure-module would
error out in the repos where the configure option is unknown.
Because we don't have a Coin configure variable for each repo,
we circumvent the issue by continuing to pass CMake-style options via
NON_QTBASE_CMAKE_ARGS instead, which does not do validation checks.
In the future, we could introduce a configure flag that disables
the validation checks.

Pick-to: 6.2 6.3
Task-number: QTQAINFRA-4357
Task-number: QTQAINFRA-4815
Change-Id: I72d8ba0b3a543b42982e22ae8d6566c0e885c446
Reviewed-by: Jörg Bornemann <joerg.bornemann@qt.io>
Reviewed-by: Toni Saario <toni.saario@qt.io>
2022-03-17 17:14:36 +01:00
..
build_qmake_examples_inner_instructions.yaml
build_qmake_examples_instructions.yaml
get_examples_source_location.yaml