Subzero: Make thread_local work under MacOS 10.6.

src/IceDefs.h

 //===- subzero/src/IceDefs.h - Common Subzero declaraions -------*- C++ -*-===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This file declares various useful types and classes that have
@@ skipping 20 matching lines @@
 #include "llvm/ADT/ilist_node.h"
 #include "llvm/ADT/iterator_range.h"
 #include "llvm/ADT/SmallBitVector.h"
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/Support/Allocator.h"
 #include "llvm/Support/Casting.h"
 #include "llvm/Support/ELF.h"
 #include "llvm/Support/raw_ostream.h"
 
+// TODO(stichnot): Define ICE_ATTRIBUTE_TLS as thread_local after all
+// compilers support that C++11 keyword.  In particular, MacOS 10.6
+// does not support it.
+#if defined (_MSC_VER)
+#define ICE_ATTRIBUTE_TLS __declspec(thread)
+#else // !_MSC_VER
+#define ICE_ATTRIBUTE_TLS __thread
+#endif // !_MSC_VER
+
 namespace Ice {
 
 class Assembler;
 class Cfg;
 class CfgNode;
 class Constant;
 class ELFObjectWriter;
 class ELFStreamer;
 class FunctionDeclaration;
 class GlobalContext;
@@ skipping 117 matching lines @@
   return llvm::make_range(Container.rbegin(), Container.rend());
 }
 template <typename T>
 llvm::iterator_range<typename T::reverse_iterator> reverse_range(T &Container) {
   return llvm::make_range(Container.rbegin(), Container.rend());
 }
 
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICEDEFS_H