text: #ifndef FWCORE_GCC11COMPATIBILITY_H
  #define FWCORE_GCC11COMPATIBILITY_H
  /*
   * set of macro to control the level of comaptibility with c++11 standard
   * includes also other macro more specific to gcc
  
   */
  
  #include "FWCore/Utilities/interface/Visibility.h"
  #include "FWCore/Utilities/interface/Likely.h"
  
  #if defined(__GCCXML__) || defined(__CINT__)
  #define CMS_NOCXX11
  #endif
  #if !GCC_PREREQUISITE(4, 6, 0) && !defined(__clang__)
  #define CMS_NOCXX11
  #endif
  
  #ifndef CMS_NOCXX11
  #if GCC_PREREQUISITE(4, 7, 0)
  #define GCC11_FINAL final
  #define GCC11_OVERRIDE override
  #elif __clang__
  // FIXME: do not know how to query for final support. It's there in any
  //        clang version we will ever use, so it's fine.
  #define GCC11_FINAL final
  #if __has_feature(cxx_override_control)
  #define GCC11_OVERRIDE override
  #endif
  #else
  #define GCC11_FINAL
  #define GCC11_OVERRIDE
  #endif  // gcc 4.7
  #else
  #define constexpr
  #define noexcept
  #define nullptr 0
  #define GCC11_FINAL
  #define GCC11_OVERRIDE
  #endif  // NOCXX11
  
  #endif  // FWCORE_GCC11COMPATIBILITY_H
  