CMakeLists.txt: explicitly set the standard to C++98

Set the C++ standard to C++98 to avoid GCC 6 compilation failures.

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 4e65579133835cd88a19c0fd97d8f5b4fe06060b..85acd38bbb7dc9b57aeb00534cb7eabda6a92649 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -22,6 +22,16 @@ set(CMAKE_OSX_DEPLOYMENT_TARGET 10.7)
 # only relevant for building shared libs but let's set it regardless
 set(CMAKE_OSX_RPATH 1)
 
+# Set the C++ standard to C++98 to avoid compilation errors on GCC 6 (which
+# defaults to C++14).
+if(CMAKE_VERSION VERSION_LESS "3.1")
+  if(CMAKE_COMPILER_IS_GNUCXX)
+    set (CMAKE_CXX_FLAGS "--std=gnu++98 ${CMAKE_CXX_FLAGS}")
+  endif()
+else()
+  set (CMAKE_CXX_STANDARD 98)
+endif()
+
 project(SimGear)
 
 # read 'version' file into a variable (stripping any newlines or spaces)