The generated configuration header of OwlPS Listener is now generated
after the dependencies checking, so that if an option was disabled
because of a missing dependency it is reflected in the generated header.
We chose a centralised approach, since threads are needed in several
modules: the find_package() is done only once in the rood directory.
Not sure it's the best approach though, but this test is several lines
long so doing that avoids duplication of this code.
- Default compiler and linker flags were added silently. They are now
set in the cache if no previous values are present.
- Debug flags and regular flags have been merged.
- Position-independent code (doesn't appear in the cache because CMake
lacks variables like CMAKE_EXE_COMPILE_FLAGS):
- Shared libraries are compiled with -fPIC.
- Executables and static libraries are compiled with -fPIE.
- Executables are linked with -pie -fPIE.