Changeset 7805:d26ebad8b7a2 changed the value of 'INCLUDE_INSTALL_DIR', in the top-level 'CMakeLists.txt', from an absolute file name to a relative file name. As a result, the -I flag in 'eigen3.pc' is invalid as of Eigen 3.2.7.
*** This bug has been marked as a duplicate of bug 1100 ***
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