Index: include/lld/ReaderWriter/ELFLinkingContext.h
===================================================================
--- include/lld/ReaderWriter/ELFLinkingContext.h
+++ include/lld/ReaderWriter/ELFLinkingContext.h
@@ -306,6 +306,14 @@
   bool armTarget1Rel() const { return _armTarget1Rel; }
   void setArmTarget1Rel(bool value) { _armTarget1Rel = value; }
 
+  /// Each time a reader reads a new file, this member function is called
+  /// with the file's ELF magics. This is supposed to "merge" all attributes
+  /// to generate output ELF file magic. This can also reject input files
+  /// if they conflict with previous input files.
+  virtual std::error_code mergeHeaderFlags(uint8_t fileClass, uint64_t flags) {
+    return std::error_code();
+  }
+
 protected:
   ELFLinkingContext(llvm::Triple triple, std::unique_ptr<TargetHandler> handler)
       : _triple(triple), _targetHandler(std::move(handler)) {}
Index: lib/ReaderWriter/ELF/ELFReader.h
===================================================================
--- lib/ReaderWriter/ELF/ELFReader.h
+++ lib/ReaderWriter/ELF/ELFReader.h
@@ -34,6 +34,10 @@
   std::error_code
   loadFile(std::unique_ptr<MemoryBuffer> mb, const class Registry &,
            std::vector<std::unique_ptr<File>> &result) const override {
+    auto &hdr = *this->elfHeader(*mb);
+    if (auto ec = _ctx.mergeHeaderFlags(hdr.getFileClass(), hdr.e_flags))
+      return ec;
+
     std::size_t maxAlignment =
         1ULL << llvm::countTrailingZeros(uintptr_t(mb->getBufferStart()));
     auto f = createELF<FileT>(llvm::object::getElfArchType(mb->getBuffer()),
Index: lib/ReaderWriter/ELF/Mips/MipsELFReader.h
===================================================================
--- lib/ReaderWriter/ELF/Mips/MipsELFReader.h
+++ /dev/null
@@ -1,67 +0,0 @@
-//===- lib/ReaderWriter/ELF/MipsELFReader.h -------------------------------===//
-//
-//                             The LLVM Linker
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-#ifndef LLD_READER_WRITER_ELF_MIPS_MIPS_ELF_READER_H
-#define LLD_READER_WRITER_ELF_MIPS_MIPS_ELF_READER_H
-
-#include "ELFReader.h"
-#include "MipsELFFile.h"
-#include "MipsELFFlagsMerger.h"
-#include "MipsLinkingContext.h"
-
-namespace lld {
-namespace elf {
-
-template <class ELFT>
-class MipsELFObjectReader
-    : public ELFObjectReader<ELFT, MipsLinkingContext, lld::elf::MipsELFFile> {
-  typedef ELFObjectReader<ELFT, MipsLinkingContext, lld::elf::MipsELFFile>
-      BaseReaderType;
-
-public:
-  MipsELFObjectReader(MipsLinkingContext &ctx)
-      : BaseReaderType(ctx), _flagMerger(ctx.getELFFlagsMerger()) {}
-
-  std::error_code
-  loadFile(std::unique_ptr<MemoryBuffer> mb, const Registry &registry,
-           std::vector<std::unique_ptr<File>> &result) const override {
-    auto &hdr = *this->elfHeader(*mb);
-    if (auto ec = _flagMerger.mergeHeaderFlags(hdr.getFileClass(), hdr.e_flags))
-      return ec;
-    return BaseReaderType::loadFile(std::move(mb), registry, result);
-  }
-
-private:
-  MipsELFFlagsMerger &_flagMerger;
-};
-
-template <class ELFT>
-class MipsELFDSOReader : public ELFDSOReader<ELFT, MipsLinkingContext> {
-  typedef ELFDSOReader<ELFT, MipsLinkingContext> BaseReaderType;
-
-public:
-  MipsELFDSOReader(MipsLinkingContext &ctx)
-      : BaseReaderType(ctx), _flagMerger(ctx.getELFFlagsMerger()) {}
-
-  std::error_code
-  loadFile(std::unique_ptr<MemoryBuffer> mb, const Registry &registry,
-           std::vector<std::unique_ptr<File>> &result) const override {
-    auto &hdr = *this->elfHeader(*mb);
-    if (auto ec = _flagMerger.mergeHeaderFlags(hdr.getFileClass(), hdr.e_flags))
-      return ec;
-    return BaseReaderType::loadFile(std::move(mb), registry, result);
-  }
-
-private:
-  MipsELFFlagsMerger &_flagMerger;
-};
-
-} // namespace elf
-} // namespace lld
-
-#endif
Index: lib/ReaderWriter/ELF/Mips/MipsLinkingContext.h
===================================================================
--- lib/ReaderWriter/ELF/Mips/MipsLinkingContext.h
+++ lib/ReaderWriter/ELF/Mips/MipsLinkingContext.h
@@ -46,8 +46,8 @@
   static const int machine = llvm::ELF::EM_MIPS;
   MipsLinkingContext(llvm::Triple triple);
 
+  std::error_code mergeHeaderFlags(uint8_t fileClass, uint64_t flags) override;
   uint32_t getMergedELFFlags() const;
-  MipsELFFlagsMerger &getELFFlagsMerger();
   void registerRelocationNames(Registry &r) override;
 
   // ELFLinkingContext
Index: lib/ReaderWriter/ELF/Mips/MipsLinkingContext.cpp
===================================================================
--- lib/ReaderWriter/ELF/Mips/MipsLinkingContext.cpp
+++ lib/ReaderWriter/ELF/Mips/MipsLinkingContext.cpp
@@ -43,12 +43,13 @@
     : ELFLinkingContext(triple, createTarget(triple, *this)),
       _flagsMerger(triple.isArch64Bit()) {}
 
-uint32_t MipsLinkingContext::getMergedELFFlags() const {
-  return _flagsMerger.getMergedELFFlags();
+std::error_code MipsLinkingContext::mergeHeaderFlags(uint8_t fileClass,
+                                                     uint64_t flags) {
+  return _flagsMerger.mergeHeaderFlags(fileClass, flags);
 }
 
-MipsELFFlagsMerger &MipsLinkingContext::getELFFlagsMerger() {
-  return _flagsMerger;
+uint32_t MipsLinkingContext::getMergedELFFlags() const {
+  return _flagsMerger.getMergedELFFlags();
 }
 
 uint64_t MipsLinkingContext::getBaseAddress() const {
Index: lib/ReaderWriter/ELF/Mips/MipsTargetHandler.h
===================================================================
--- lib/ReaderWriter/ELF/Mips/MipsTargetHandler.h
+++ lib/ReaderWriter/ELF/Mips/MipsTargetHandler.h
@@ -9,8 +9,9 @@
 #ifndef LLD_READER_WRITER_ELF_MIPS_MIPS_TARGET_HANDLER_H
 #define LLD_READER_WRITER_ELF_MIPS_MIPS_TARGET_HANDLER_H
 
+#include "ELFReader.h"
 #include "MipsDynamicLibraryWriter.h"
-#include "MipsELFReader.h"
+#include "MipsELFFile.h"
 #include "MipsExecutableWriter.h"
 #include "MipsLinkingContext.h"
 #include "MipsRelocationHandler.h"
@@ -85,6 +86,9 @@
 
 /// \brief TargetHandler for Mips
 template <class ELFT> class MipsTargetHandler final : public TargetHandler {
+  typedef ELFObjectReader<ELFT, MipsLinkingContext, lld::elf::MipsELFFile> ObjReader;
+  typedef ELFDSOReader<ELFT, MipsLinkingContext> DSOReader;
+
 public:
   MipsTargetHandler(MipsLinkingContext &ctx)
       : _ctx(ctx), _targetLayout(new MipsTargetLayout<ELFT>(ctx)),
@@ -92,11 +96,11 @@
             createMipsRelocationHandler<ELFT>(ctx, *_targetLayout)) {}
 
   std::unique_ptr<Reader> getObjReader() override {
-    return llvm::make_unique<MipsELFObjectReader<ELFT>>(_ctx);
+    return llvm::make_unique<ObjReader>(_ctx);
   }
 
   std::unique_ptr<Reader> getDSOReader() override {
-    return llvm::make_unique<MipsELFDSOReader<ELFT>>(_ctx);
+    return llvm::make_unique<DSOReader>(_ctx);
   }
 
   const TargetRelocationHandler &getRelocationHandler() const override {