9545 Global visibility of C11 functions in C++11 and C++17

*** 78,87 ****
--- 78,99 ----
  using std::system;
  using std::wcstombs;
  using std::wctomb;
  #endif
  
+ /*
+  * Allow global visibility for symbols defined in
+  * C++ "std" namespace in <iso/stdlib_c11.h>.
+  */
+ #if __cplusplus >= 201103L
+ using std::at_quick_exit;
+ using std::quick_exit;
+ #endif
+ #if __cplusplus >= 201703L
+ using std::aligned_alloc;
+ #endif
+ 
  #ifdef  __cplusplus
  extern "C" {
  #endif
  
  #ifndef _UID_T