Import prebuilt clang toolchain for linux.
diff --git a/linux-x64/clang/include/llvm/MC/MCSymbolWasm.h b/linux-x64/clang/include/llvm/MC/MCSymbolWasm.h
new file mode 100644
index 0000000..10eadb0
--- /dev/null
+++ b/linux-x64/clang/include/llvm/MC/MCSymbolWasm.h
@@ -0,0 +1,96 @@
+//===- MCSymbolWasm.h -  ----------------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+#ifndef LLVM_MC_MCSYMBOLWASM_H
+#define LLVM_MC_MCSYMBOLWASM_H
+
+#include "llvm/BinaryFormat/Wasm.h"
+#include "llvm/MC/MCSymbol.h"
+
+namespace llvm {
+
+class MCSymbolWasm : public MCSymbol {
+  wasm::WasmSymbolType Type = wasm::WASM_SYMBOL_TYPE_DATA;
+  bool IsWeak = false;
+  bool IsHidden = false;
+  bool IsComdat = false;
+  std::string ModuleName;
+  SmallVector<wasm::ValType, 1> Returns;
+  SmallVector<wasm::ValType, 4> Params;
+  wasm::WasmGlobalType GlobalType;
+  bool ParamsSet = false;
+  bool ReturnsSet = false;
+  bool GlobalTypeSet = false;
+
+  /// An expression describing how to calculate the size of a symbol. If a
+  /// symbol has no size this field will be NULL.
+  const MCExpr *SymbolSize = nullptr;
+
+public:
+  // Use a module name of "env" for now, for compatibility with existing tools.
+  // This is temporary, and may change, as the ABI is not yet stable.
+  MCSymbolWasm(const StringMapEntry<bool> *Name, bool isTemporary)
+      : MCSymbol(SymbolKindWasm, Name, isTemporary),
+        ModuleName("env") {}
+  static bool classof(const MCSymbol *S) { return S->isWasm(); }
+
+  const MCExpr *getSize() const { return SymbolSize; }
+  void setSize(const MCExpr *SS) { SymbolSize = SS; }
+
+  bool isFunction() const { return Type == wasm::WASM_SYMBOL_TYPE_FUNCTION; }
+  bool isData() const { return Type == wasm::WASM_SYMBOL_TYPE_DATA; }
+  bool isGlobal() const { return Type == wasm::WASM_SYMBOL_TYPE_GLOBAL; }
+  wasm::WasmSymbolType getType() const { return Type; }
+  void setType(wasm::WasmSymbolType type) { Type = type; }
+
+  bool isWeak() const { return IsWeak; }
+  void setWeak(bool isWeak) { IsWeak = isWeak; }
+
+  bool isHidden() const { return IsHidden; }
+  void setHidden(bool isHidden) { IsHidden = isHidden; }
+
+  bool isComdat() const { return IsComdat; }
+  void setComdat(bool isComdat) { IsComdat = isComdat; }
+
+  const StringRef getModuleName() const { return ModuleName; }
+  void setModuleName(StringRef Name) { ModuleName = Name; }
+
+  const SmallVector<wasm::ValType, 1> &getReturns() const {
+    assert(ReturnsSet);
+    return Returns;
+  }
+
+  void setReturns(SmallVectorImpl<wasm::ValType> &&Rets) {
+    ReturnsSet = true;
+    Returns = std::move(Rets);
+  }
+
+  const SmallVector<wasm::ValType, 4> &getParams() const {
+    assert(ParamsSet);
+    return Params;
+  }
+
+  void setParams(SmallVectorImpl<wasm::ValType> &&Pars) {
+    ParamsSet = true;
+    Params = std::move(Pars);
+  }
+
+  const wasm::WasmGlobalType &getGlobalType() const {
+    assert(GlobalTypeSet);
+    return GlobalType;
+  }
+
+  void setGlobalType(wasm::WasmGlobalType GT) {
+    GlobalTypeSet = true;
+    GlobalType = GT;
+  }
+};
+
+}  // end namespace llvm
+
+#endif // LLVM_MC_MCSYMBOLWASM_H