Index: lld/COFF/DLL.h
===================================================================
--- lld/COFF/DLL.h
+++ lld/COFF/DLL.h
@@ -39,7 +39,7 @@
   std::vector<std::unique_ptr<Chunk>> Lookups;
   std::vector<std::unique_ptr<Chunk>> Addresses;
   std::vector<std::unique_ptr<Chunk>> Hints;
-  std::map<StringRef, std::unique_ptr<Chunk>> DLLNames;
+  std::vector<std::unique_ptr<Chunk>> DLLNames;
 };
 
 // Windows-specific.
@@ -67,7 +67,7 @@
   std::vector<std::unique_ptr<Chunk>> Names;
   std::vector<std::unique_ptr<Chunk>> HintNames;
   std::vector<std::unique_ptr<Chunk>> Thunks;
-  std::map<StringRef, std::unique_ptr<Chunk>> DLLNames;
+  std::vector<std::unique_ptr<Chunk>> DLLNames;
 };
 
 // Windows-specific.
Index: lld/COFF/DLL.cpp
===================================================================
--- lld/COFF/DLL.cpp
+++ lld/COFF/DLL.cpp
@@ -394,10 +394,8 @@
     V.push_back(C.get());
   for (std::unique_ptr<Chunk> &C : Hints)
     V.push_back(C.get());
-  for (auto &P : DLLNames) {
-    std::unique_ptr<Chunk> &C = P.second;
+  for (std::unique_ptr<Chunk> &C : DLLNames)
     V.push_back(C.get());
-  }
   return V;
 }
 
@@ -406,8 +404,6 @@
 
   // Create .idata contents for each DLL.
   for (std::vector<DefinedImportData *> &Syms : V) {
-    StringRef Name = Syms[0]->getDLLName();
-
     // Create lookup and address tables. If they have external names,
     // we need to create HintName chunks to store the names.
     // If they don't (if they are import-by-ordinals), we store only
@@ -433,9 +429,8 @@
       Syms[I]->setLocation(Addresses[Base + I].get());
 
     // Create the import table header.
-    if (!DLLNames.count(Name))
-      DLLNames[Name] = make_unique<StringChunk>(Name);
-    auto Dir = make_unique<ImportDirectoryChunk>(DLLNames[Name].get());
+    DLLNames.push_back(make_unique<StringChunk>(Syms[0]->getDLLName()));
+    auto Dir = make_unique<ImportDirectoryChunk>(DLLNames.back().get());
     Dir->LookupTab = Lookups[Base].get();
     Dir->AddressTab = Addresses[Base].get();
     Dirs.push_back(std::move(Dir));
@@ -452,10 +447,8 @@
     V.push_back(C.get());
   for (std::unique_ptr<Chunk> &C : HintNames)
     V.push_back(C.get());
-  for (auto &P : DLLNames) {
-    std::unique_ptr<Chunk> &C = P.second;
+  for (std::unique_ptr<Chunk> &C : DLLNames)
     V.push_back(C.get());
-  }
   return V;
 }
 
@@ -478,12 +471,9 @@
 
   // Create .didat contents for each DLL.
   for (std::vector<DefinedImportData *> &Syms : V) {
-    StringRef Name = Syms[0]->getDLLName();
-
     // Create the delay import table header.
-    if (!DLLNames.count(Name))
-      DLLNames[Name] = make_unique<StringChunk>(Name);
-    auto Dir = make_unique<DelayDirectoryChunk>(DLLNames[Name].get());
+    DLLNames.push_back(make_unique<StringChunk>(Syms[0]->getDLLName()));
+    auto Dir = make_unique<DelayDirectoryChunk>(DLLNames.back().get());
 
     size_t Base = Addresses.size();
     for (DefinedImportData *S : Syms) {