Try to force C++11 for older compilers.

cmake_support/OST.cmake

@@ -897,7 +897,7 @@ macro(setup_compiler_flags)
       set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -fno-strict-aliasing" )
     endif()
     #message(STATUS "GCC VERSION " ${_GCC_VERSION})
-    if ((ENABLE_INFO OR ENABLE_GUI) AND _GCC_VERSION LESS "60")
+    if (_GCC_VERSION LESS "60")
       # for older compilers we need to enable C++11 for Qt5
       set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -std=c++11")
     endif()

modules/doc/install.rst

@@ -23,7 +23,7 @@ the steps which we describe in detail below. In essence, these steps are:
 Installing the Dependencies
 --------------------------------------------------------------------------------
 
-OpenStructure requires a c++11 enabled compiler (e.g. recent gcc/clang) and uses 
+OpenStructure requires a C++11 enabled compiler (e.g. recent gcc/clang) and uses 
 a bunch of open-source libraries. If you haven't already installed them, please 
 install them now! Where appropriate, the minimally required version is given in 
 parentheses.