diff --git a/lib/Analysis/ModuleSummaryAnalysis.cpp b/lib/Analysis/ModuleSummaryAnalysis.cpp
index 6c207f84286..26706f5509b 100644
--- a/lib/Analysis/ModuleSummaryAnalysis.cpp
+++ b/lib/Analysis/ModuleSummaryAnalysis.cpp
@@ -330,6 +330,7 @@ ModuleSummaryIndex llvm::buildModuleSummaryIndex(
     const Module &M,
     std::function<BlockFrequencyInfo *(const Function &F)> GetBFICallback,
     ProfileSummaryInfo *PSI) {
+  assert(PSI);
   ModuleSummaryIndex Index;
 
   // Identify the local values in the llvm.used and llvm.compiler.used sets,
diff --git a/lib/LTO/ThinLTOCodeGenerator.cpp b/lib/LTO/ThinLTOCodeGenerator.cpp
index b4ee7c2b2fb..f3d441db98c 100644
--- a/lib/LTO/ThinLTOCodeGenerator.cpp
+++ b/lib/LTO/ThinLTOCodeGenerator.cpp
@@ -446,7 +446,7 @@ ProcessThinLTOModule(Module &TheModule, ModuleSummaryIndex &Index,
     {
       raw_svector_ostream OS(OutputBuffer);
       ProfileSummaryInfo PSI(TheModule);
-      auto Index = buildModuleSummaryIndex(TheModule, nullptr, nullptr);
+      auto Index = buildModuleSummaryIndex(TheModule, nullptr, &PSI);
       WriteBitcodeToFile(&TheModule, OS, true, &Index);
     }
     return make_unique<ObjectMemoryBuffer>(std::move(OutputBuffer));
diff --git a/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp b/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp
index d3a3c24ce7b..68884ce25bf 100644
--- a/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp
+++ b/lib/Transforms/IPO/ThinLTOBitcodeWriter.cpp
@@ -16,6 +16,7 @@
 
 #include "llvm/Analysis/BasicAliasAnalysis.h"
 #include "llvm/Analysis/ModuleSummaryAnalysis.h"
+#include "llvm/Analysis/ProfileSummaryInfo.h"
 #include "llvm/Analysis/TypeMetadataUtils.h"
 #include "llvm/Bitcode/BitcodeWriter.h"
 #include "llvm/IR/Constants.h"
@@ -320,7 +321,8 @@ void splitAndWriteThinLTOBitcode(
 
 
   // FIXME: Try to re-use BSI and PFI from the original module here.
-  ModuleSummaryIndex Index = buildModuleSummaryIndex(M, nullptr, nullptr);
+  ProfileSummaryInfo PSI(M);
+  ModuleSummaryIndex Index = buildModuleSummaryIndex(M, nullptr, &PSI);
 
   SmallVector<char, 0> Buffer;