Stops leaking very long source paths in build directories; makes them
deterministic.
Besides satisfying a CMake requirement, the new empty_file.c provide a
clue that the actual test code is not in the directory of the test case.
See https://github.com/zephyrproject-rtos/hal_nordic/pull/6 and
https://gitlab.kitware.com/cmake/cmake/issues/19475 for more details.
- Test with a simple:
sanitycheck -T $ZEPHYR_BASE/tests/subsys/settings/functional/
- Before:
CMakeFiles
├── app.dir
│ ├── HOME
│ │ └── JOHN
│ │ └── zephyrproject
│ │ └── zephyr
│ │ └── tests
│ │ └── subsys
│ │ └── settings
│ │ └── functional
│ │ └── src
│ │ └── settings_basic_test.c.obj
- After:
func_test_bindir/
├── CMakeFiles
│ └── settings_func_test.dir
│ └── settings_basic_test.c.obj
│
├── libsettings_func_test.a
Signed-off-by: Marc Herbert <marc.herbert@intel.com>
b4282bf72d