SPDX-License-Identifier: GPL-3.0-or-later
SPDX-FileCopyrightText: 2022 Carles Fernandez-Prades <carles.fernandez@cttc.es>
--- CMakeLists.txt  2022-07-10 09:58:33.000000000 +0200
+++ CMakeLists.txt  2022-07-10 10:02:36.000000000 +0200
@@ -6,7 +6,7 @@
 #           Is dependend on by $GNSSTK/build.sh
 #============================================================
 
-cmake_minimum_required( VERSION 2.8.5 )
+cmake_minimum_required( VERSION 2.8.12 )
 
 project( GNSSTK )
 set( GNSSTK_VERSION_MAJOR "13" )
@@ -21,6 +21,15 @@
 
 # This sets up variables contining GNU standard installation locations.
 include( GNUInstallDirs )
+if(POLICY CMP0063)
+    cmake_policy(SET CMP0063 NEW)
+    set(CMAKE_CXX_VISIBILITY_PRESET hidden)
+    set(CMAKE_VISIBILITY_INLINES_HIDDEN 1)
+else()
+    if((CMAKE_CXX_COMPILER_ID MATCHES "Clang" OR CMAKE_CXX_COMPILER_ID STREQUAL "GNU") AND NOT WIN32)
+        add_definitions(-fvisibility=hidden)
+    endif()
+endif()
 
 # Set a filename for collecting exported targets.
 set( EXPORT_TARGETS_FILENAME "GNSSTKTargets" )
@@ -177,7 +186,7 @@
 elseif( WIN32 )
   add_library( gnsstk ${GNSSTK_SRC_FILES} ${GNSSTK_INC_FILES} )
 else()
-  add_library( gnsstk SHARED ${GNSSTK_SRC_FILES} ${GNSSTK_INC_FILES} )
+  add_library( gnsstk STATIC ${GNSSTK_SRC_FILES} ${GNSSTK_INC_FILES} )
 endif()
 
 # always generate the header because it's an include file whose