1 files changed, 67 insertions, 0 deletions
diff --git a/llvm/include/llvm/ADT/hash_set.in b/llvm/include/llvm/ADT/hash_set.in
new file mode 100644
index 00000000000..6da8c7f6a31
--- /dev/null
+++ b/llvm/include/llvm/ADT/hash_set.in
@@ -0,0 +1,67 @@
+//===-- llvm/ADT/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 LLVM_ADT_HASH_SET
+#define LLVM_ADT_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 <llvm/ADT/HashExtras.h>
+
+#endif