tree ebdbb18bc98c88489a0247a618abcc62793d6df0
parent 0e811b0881f1f21df0ae04fd745ae4ba5189cac1
author Alex Stewart <alexs.mac@gmail.com> 1398942406 +0100
committer Sameer Agarwal <sameeragarwal@google.com> 1399037604 +0000

Export Ceres compile definitions to targets compiled against Ceres.

- Previously all Ceres compile definitions were private to Ceres, that
  is they were not exported to users via the CMake export mechanism.
- Now that we use compile definitions in public (installed) Ceres
  headers, we need to export the Ceres compile definitions.
- If we did not do this, then the client's code 'see's' a different
  version of the Ceres headers to those which were in fact compiled,
  or in the case of shared_ptr, may not find the required header.

- This patch makes use of the new, in CMake 2.8.11, function:
  target_compile_definitions() to export all of the Ceres compile
  definitions using CMake's export functionality.
- For CMake versions < 2.8.11, we have to use the blunter instrument of
  calling add_definitions() in CeresConfig.cmake (invoked by a call to
  find_package(Ceres)).  This is messy because it ends up adding the
  Ceres compile definitions to any target declared in the user's code
  after the call to find_package(Ceres).  Although this should do no
  harm as all of our defines are prefaced with CERES_, so any
  unintentional name clashes are unlikely.

Change-Id: I5dea80949190eaf4fb08ea4ac568ce28c32dd4e0