From 06f724318a93958d21c7eab413781ebfc45f57cf Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Nehil=20Dan=C4=B1=C5=9F?= <nehild@outlook.com>
Date: Thu, 17 Aug 2023 17:26:46 +0200
Subject: [PATCH] ADDED: a check for cmake version (#203)

* ADDED: a check for cmake version

* Reuse a bit the code and add a comment

---------

Co-authored-by: Ignacio Vizzo <ignaciovizzo@gmail.com>
---
 cpp/kiss_icp/3rdparty/eigen/eigen.cmake | 15 +++++++++------
 cpp/kiss_icp/3rdparty/tbb/tbb.cmake     | 15 +++++++++------
 2 files changed, 18 insertions(+), 12 deletions(-)

diff --git a/cpp/kiss_icp/3rdparty/eigen/eigen.cmake b/cpp/kiss_icp/3rdparty/eigen/eigen.cmake
index 7de1864b..c17460e7 100644
--- a/cpp/kiss_icp/3rdparty/eigen/eigen.cmake
+++ b/cpp/kiss_icp/3rdparty/eigen/eigen.cmake
@@ -35,10 +35,13 @@ include(FetchContent)
 FetchContent_Declare(eigen URL https://github.com/nachovizzo/eigen/archive/refs/tags/3.4.90.tar.gz)
 if(NOT eigen_POPULATED)
   FetchContent_Populate(eigen)
-  add_subdirectory(${eigen_SOURCE_DIR} ${eigen_BINARY_DIR} SYSTEM EXCLUDE_FROM_ALL)
-endif()
-
-if(${CMAKE_VERSION} VERSION_LESS 3.25)
-  get_target_property(eigen_include_dirs eigen INTERFACE_INCLUDE_DIRECTORIES)
-  set_target_properties(eigen PROPERTIES INTERFACE_SYSTEM_INCLUDE_DIRECTORIES "${eigen_include_dirs}")
+  if(${CMAKE_VERSION} GREATER_EQUAL 3.25)
+    add_subdirectory(${eigen_SOURCE_DIR} ${eigen_BINARY_DIR} SYSTEM EXCLUDE_FROM_ALL)
+  else()
+    # Emulate the SYSTEM flag introduced in CMake 3.25. Withouth this flag the compiler will
+    # consider this 3rdparty headers as source code and fail due the -Werror flag.
+    add_subdirectory(${eigen_SOURCE_DIR} ${eigen_BINARY_DIR} EXCLUDE_FROM_ALL)
+    get_target_property(eigen_include_dirs eigen INTERFACE_INCLUDE_DIRECTORIES)
+    set_target_properties(eigen PROPERTIES INTERFACE_SYSTEM_INCLUDE_DIRECTORIES "${eigen_include_dirs}")
+  endif()
 endif()
diff --git a/cpp/kiss_icp/3rdparty/tbb/tbb.cmake b/cpp/kiss_icp/3rdparty/tbb/tbb.cmake
index 576bfc64..64482ceb 100644
--- a/cpp/kiss_icp/3rdparty/tbb/tbb.cmake
+++ b/cpp/kiss_icp/3rdparty/tbb/tbb.cmake
@@ -31,10 +31,13 @@ include(FetchContent)
 FetchContent_Declare(tbb URL https://github.com/oneapi-src/oneTBB/archive/refs/tags/v2021.8.0.tar.gz)
 if(NOT tbb_POPULATED)
   FetchContent_Populate(tbb)
-  add_subdirectory(${tbb_SOURCE_DIR} ${tbb_BINARY_DIR} SYSTEM EXCLUDE_FROM_ALL)
-endif()
-
-if(${CMAKE_VERSION} VERSION_LESS 3.25)
-  get_target_property(tbb_include_dirs tbb INTERFACE_INCLUDE_DIRECTORIES)
-  set_target_properties(tbb PROPERTIES INTERFACE_SYSTEM_INCLUDE_DIRECTORIES "${tbb_include_dirs}")
+  if(${CMAKE_VERSION} GREATER_EQUAL 3.25)
+    add_subdirectory(${tbb_SOURCE_DIR} ${tbb_BINARY_DIR} SYSTEM EXCLUDE_FROM_ALL)
+  else()
+    # Emulate the SYSTEM flag introduced in CMake 3.25. Withouth this flag the compiler will
+    # consider this 3rdparty headers as source code and fail due the -Werror flag.
+    add_subdirectory(${tbb_SOURCE_DIR} ${tbb_BINARY_DIR} EXCLUDE_FROM_ALL)
+    get_target_property(tbb_include_dirs tbb INTERFACE_INCLUDE_DIRECTORIES)
+    set_target_properties(tbb PROPERTIES INTERFACE_SYSTEM_INCLUDE_DIRECTORIES "${tbb_include_dirs}")
+  endif()
 endif()