CMake has a built-in property, `POSITION_INDEPENDENT_CODE`, that determines
if code will be built with `-fPIC`. This property is `True` by default for
`SHARED` and `MODULE` library targets and `False` otherwise. Previously,
we were always passing the `-fPIC` flag manually. With this change, we set
the appropriate CMake variable that will enable the property for all
compile jobs.
Furthermore, with CMake policy CMP0083 set to "new" (which happens by
default when the `cmake_minimum_required` version is >=3.14), CMake has
built-in support for passing the `-fpie` flag when building executables. It
uses the same property, `POSITION_INDEPENDENT_CODE`, so setting this
property (and enabling it with the CMake `CheckPIESupported` module) allows
us to use CMake's built-in support for these flags.
Signed-off-by: Chris Burel <burelc@amazon.com>
Chris Burel
8acda7d04d