- Use target_compile_features() to specify the C++11 dependency for
Ceres if the CXX11 option is enabled and the current CMake version
supports it (>= 3.1). Otherwise fall back onto our existing
target_compile_options() solution if available.
- We prefer the use of target_compile_features() if available as it more
gracefully handles ‘upgrading’ of the C++ standard in client projects
that depend upon Ceres, e.g. if the client requires C++14. The
current solution may fail to produce the expected result in this case
as raised in
https://github.com/ceres-solver/ceres-solver/issues/273.
Change-Id: Ib3cff8d4b9fe93fa6d6b376b4dd53923bb1c4ecc
Alex Stewart