Subzero: Improve class definition hygiene.

src/IceFixups.h

 //===- subzero/src/IceFixups.h - Assembler fixup kinds ----------*- 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 generic fixup types.
 //
 //===----------------------------------------------------------------------===//
 
 #ifndef SUBZERO_SRC_ICEFIXUPS_H
 #define SUBZERO_SRC_ICEFIXUPS_H
 
 #include "IceDefs.h"
 
 namespace Ice {
 
 // Each target and container format has a different namespace of relocations.
 // This holds the specific target+container format's relocation number.
 typedef uint32_t FixupKind;
 
 // Assembler fixups are positions in generated code/data that hold relocation
 // information that needs to be processed before finalizing the code/data.
 struct AssemblerFixup {
+  AssemblerFixup &operator=(const AssemblerFixup &) = delete;
+
 public:
+  AssemblerFixup() : position_(0), kind_(0), value_(nullptr) {}
+  AssemblerFixup(const AssemblerFixup &) = default;
   intptr_t position() const { return position_; }
   void set_position(intptr_t Position) { position_ = Position; }
 
   FixupKind kind() const { return kind_; }
   void set_kind(FixupKind Kind) { kind_ = Kind; }
 
   RelocOffsetT offset() const;
   IceString symbol(const GlobalContext *Ctx) const;
   void set_value(const Constant *Value) { value_ = Value; }
 
   void emit(GlobalContext *Ctx) const;
 
 private:
   intptr_t position_;
   FixupKind kind_;
   const Constant *value_;
 };
 
 typedef std::vector<AssemblerFixup> FixupList;
 typedef std::vector<AssemblerFixup *> FixupRefList;
 
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICEFIXUPS_H