Merge pull request #2628 from QiJune/feature/add_eigen_cmake

add eigen as cmake external project

CMakeLists.txt

@@ -92,6 +92,7 @@ include(external/openblas)  # download, build, install openblas
 include(external/swig)      # download, build, install swig
 include(external/warpctc)   # download, build, install warpctc
 include(external/any)       # download libn::any
+include(external/eigen)     # download eigen3
 
 include(generic)            # simplify cmake module
 include(package)            # set paddle packages

cmake/external/eigen.cmake

+INCLUDE(ExternalProject)
+
+SET(EIGEN_SOURCE_DIR ${THIRD_PARTY_PATH}/eigen3)
+
+INCLUDE_DIRECTORIES(${EIGEN_SOURCE_DIR}/src/eigen3)
+
+ExternalProject_Add(
+    eigen3
+    ${EXTERNAL_PROJECT_LOG_ARGS}
+    URL            "https://bitbucket.org/eigen/eigen/get/3.3.4.tar.gz"
+    URL_MD5        "1a47e78efe365a97de0c022d127607c3"
+    PREFIX          ${EIGEN_SOURCE_DIR}
+    UPDATE_COMMAND  ""
+    CONFIGURE_COMMAND ""
+    BUILD_COMMAND     ""
+    INSTALL_COMMAND   ""
+    TEST_COMMAND      ""
+)
+
+LIST(APPEND external_project_dependencies eigen3)