There was a recent behavior change where the public CMake API
qt_add_plugin API took into account the value of BUILD_SHARED_LIBS
to decide whether the plugin should be a static or shared library.
Instead, use the following new behavior
- If no explicit option STATIC / SHARED option is passed, default to
whatever flavor Qt was built as.
Aka if Qt was configured with -shared, qt_add_plugin defaults
to creating shared plugins. If it's a -static Qt, create static
plugins.
- If an explicit STATIC / SHARED option is set, override the default
computed value with the given value.
As a result BUILD_SHARED_LIBS does not affect Qt plugins anymore. This
is more in line with Qt expectations.
Add SHARED as a new valid option to pass to qt_add_plugin (it wasn't
before).
Add tests to check for the above behavior.
Amends aa4a1006cb
Pick-to: 6.1
Fixes: QTBUG-92361
Task-number: QTBUG-88763
Change-Id: Iae806024ddd5cf10cfe58ddbcebd2818084b0bd7
Reviewed-by: Joerg Bornemann <joerg.bornemann@qt.io>
d0c2425d79