diff --git a/llvm/include/llvm/Bitcode/BitcodeWriter.h b/llvm/include/llvm/Bitcode/BitcodeWriter.h
--- a/llvm/include/llvm/Bitcode/BitcodeWriter.h
+++ b/llvm/include/llvm/Bitcode/BitcodeWriter.h
@@ -153,6 +153,10 @@
                             *ModuleToSummariesForIndex = nullptr);
 
   /// Save a copy of the llvm IR as data in the __LLVM,__bitcode section.
+  /// If available, pass the serialized module via the Buf parameter. If not,
+  /// pass an empty (default-initialized) MemoryBufferRef, and the serialization
+  /// will be handled by this API. The same behavior happens if the provided Buf
+  /// is not bitcode (i.e. if it's invalid data or even textual LLVM assembly).
   void EmbedBitcodeInModule(Module &M, MemoryBufferRef Buf, bool EmbedBitcode,
                             bool EmbedMarker,
                             const std::vector<uint8_t> *CmdArgs);
diff --git a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
--- a/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
+++ b/llvm/lib/Bitcode/Writer/BitcodeWriter.cpp
@@ -4829,11 +4829,10 @@
   std::string Data;
   ArrayRef<uint8_t> ModuleData;
   Triple T(M.getTargetTriple());
-  // Create a constant that contains the bitcode.
-  // In case of embedding a marker, ignore the input Buf and use the empty
-  // ArrayRef. It is also legal to create a bitcode marker even Buf is empty.
+
   if (EmbedBitcode) {
-    if (!isBitcode((const unsigned char *)Buf.getBufferStart(),
+    if (Buf.getBufferSize() == 0 ||
+        !isBitcode((const unsigned char *)Buf.getBufferStart(),
                    (const unsigned char *)Buf.getBufferEnd())) {
       // If the input is LLVM Assembly, bitcode is produced by serializing
       // the module. Use-lists order need to be preserved in this case.
diff --git a/llvm/lib/LTO/LTOBackend.cpp b/llvm/lib/LTO/LTOBackend.cpp
--- a/llvm/lib/LTO/LTOBackend.cpp
+++ b/llvm/lib/LTO/LTOBackend.cpp
@@ -353,13 +353,7 @@
 static void EmitBitcodeSection(Module &M) {
   if (!EmbedBitcode)
     return;
-  SmallVector<char, 0> Buffer;
-  raw_svector_ostream OS(Buffer);
-  WriteBitcodeToFile(M, OS);
-
-  std::unique_ptr<MemoryBuffer> Buf(
-      new SmallVectorMemoryBuffer(std::move(Buffer)));
-  llvm::EmbedBitcodeInModule(M, Buf->getMemBufferRef(), /*EmbedBitcode*/ true,
+  llvm::EmbedBitcodeInModule(M, llvm::MemoryBufferRef(), /*EmbedBitcode*/ true,
                              /*EmbedMarker*/ false, /*CmdArgs*/ nullptr);
 }