llvm/include/Support/hash_set.in

//===-- Support/hash_set - "Portable" wrapper around hash_set ---*- C++ -*-===//
// 
//                     The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
// 
//===----------------------------------------------------------------------===//
// vim:ft=cpp
//
// This file provides a wrapper around the mysterious <hash_set> header file
// that seems to move around between GCC releases into and out of namespaces at
// will.  #including this header will cause hash_set to be available in the
// global namespace.
//
//===----------------------------------------------------------------------===//

#ifndef SUPPORT_HASH_SET
#define SUPPORT_HASH_SET

// Compiler Support Matrix
//
// Version   Namespace   Header File
//  2.95.x       ::        hash_set
//  3.0.4       std      ext/hash_set
//  3.1      __gnu_cxx   ext/hash_set
//

// GCC versions 3.1 and later put hash_set in <ext/hash_set> and in
// the __gnu_cxx namespace.
#if @HAVE_GNU_EXT_HASH_SET@
# include <ext/hash_set>
# ifndef HASH_NAMESPACE
#  define HASH_NAMESPACE __gnu_cxx
# endif

// GCC 3.0.x puts hash_set in <ext/hash_set> and in the std namespace.
#elif @HAVE_STD_EXT_HASH_SET@
# include <ext/hash_set>
# ifndef HASH_NAMESPACE
#  define HASH_NAMESPACE std
# endif

// Older compilers such as GCC before version 3.0 do not keep
// extensions in the `ext' directory, and ignore the `std' namespace.
#elif @HAVE_GLOBAL_HASH_SET@
# include <hash_set>
# ifndef HASH_NAMESPACE
#  define HASH_NAMESPACE std
# endif

// Give a warning if we couldn't find it, instead of (or in addition to)
// randomly doing something dumb.
#else
# warning "Autoconfiguration failed to find the hash_set header file."
#endif

using HASH_NAMESPACE::hash_set;
using HASH_NAMESPACE::hash;

// Include vector because ext/hash_set includes stl_vector.h and leaves
// out specializations like stl_bvector.h, causing link conflicts.
#include <vector>

#include <Support/HashExtras.h>

#endif