diff --git a/llvm/include/llvm/Object/ArchiveWriter.h b/llvm/include/llvm/Object/ArchiveWriter.h
--- a/llvm/include/llvm/Object/ArchiveWriter.h
+++ b/llvm/include/llvm/Object/ArchiveWriter.h
@@ -39,6 +39,13 @@
                    bool WriteSymtab, object::Archive::Kind Kind,
                    bool Deterministic, bool Thin,
                    std::unique_ptr<MemoryBuffer> OldArchiveBuf = nullptr);
+
+Error writeArchiveBuffer(StringRef ArcName,
+                         ArrayRef<NewArchiveMember> NewMembers,
+                         bool WriteSymtab, object::Archive::Kind Kind,
+                         bool Deterministic, bool Thin,
+                         std::unique_ptr<MemoryBuffer> &ReturnBuffer,
+                         std::unique_ptr<MemoryBuffer> OldArchiveBuf = nullptr);
 }
 
 #endif
diff --git a/llvm/lib/Object/ArchiveWriter.cpp b/llvm/lib/Object/ArchiveWriter.cpp
--- a/llvm/lib/Object/ArchiveWriter.cpp
+++ b/llvm/lib/Object/ArchiveWriter.cpp
@@ -552,10 +552,11 @@
   return std::string(Relative.str());
 }
 
-Error writeArchive(StringRef ArcName, ArrayRef<NewArchiveMember> NewMembers,
-                   bool WriteSymtab, object::Archive::Kind Kind,
-                   bool Deterministic, bool Thin,
-                   std::unique_ptr<MemoryBuffer> OldArchiveBuf) {
+static Expected<sys::fs::TempFile>
+writeArchiveInFD(StringRef ArcName, ArrayRef<NewArchiveMember> NewMembers,
+                 bool WriteSymtab, object::Archive::Kind Kind,
+                 bool Deterministic, bool Thin,
+                 std::unique_ptr<MemoryBuffer> OldArchiveBuf) {
   assert((!Thin || !isBSDLike(Kind)) && "Only the gnu format has a thin mode");
 
   SmallString<0> SymNamesBuf;
@@ -566,7 +567,7 @@
   Expected<std::vector<MemberData>> DataOrErr = computeMemberData(
       StringTable, SymNames, Kind, Thin, Deterministic, NewMembers);
   if (Error E = DataOrErr.takeError())
-    return E;
+    return std::move(E);
   std::vector<MemberData> &Data = *DataOrErr;
 
   if (!StringTableBuf.empty())
@@ -639,7 +640,43 @@
   // closed before we attempt to rename.
   OldArchiveBuf.reset();
 
+  return Temp;
+}
+
+Error writeArchive(StringRef ArcName, ArrayRef<NewArchiveMember> NewMembers,
+                   bool WriteSymtab, object::Archive::Kind Kind,
+                   bool Deterministic, bool Thin,
+                   std::unique_ptr<MemoryBuffer> OldArchiveBuf) {
+
+  Expected<sys::fs::TempFile> Temp =
+      writeArchiveInFD(ArcName, NewMembers, WriteSymtab, Kind, Deterministic,
+                       Thin, std::move(OldArchiveBuf));
+  if (!Temp)
+    return Temp.takeError();
+
   return Temp->keep(ArcName);
 }
 
+Error writeArchiveBuffer(StringRef ArcName,
+                         ArrayRef<NewArchiveMember> NewMembers,
+                         bool WriteSymtab, object::Archive::Kind Kind,
+                         bool Deterministic, bool Thin,
+                         std::unique_ptr<MemoryBuffer> &ReturnBuffer,
+                         std::unique_ptr<MemoryBuffer> OldArchiveBuf) {
+
+  Expected<sys::fs::TempFile> Temp =
+      writeArchiveInFD(ArcName, NewMembers, WriteSymtab, Kind, Deterministic,
+                       Thin, std::move(OldArchiveBuf));
+  if (!Temp)
+    return Temp.takeError();
+
+  ErrorOr<std::unique_ptr<MemoryBuffer>> Ret =
+      MemoryBuffer::getOpenFile(Temp->FD, ArcName, -1);
+  if (std::error_code EC = Ret.getError())
+    return errorCodeToError(EC);
+
+  ReturnBuffer = std::move(Ret.get());
+  return Temp->discard();
+}
+
 } // namespace llvm