diff --git a/clang/include/clang/Frontend/ASTUnit.h b/clang/include/clang/Frontend/ASTUnit.h
index a36655150d4ec9..50ab86ebad9727 100644
--- a/clang/include/clang/Frontend/ASTUnit.h
+++ b/clang/include/clang/Frontend/ASTUnit.h
@@ -172,7 +172,7 @@ class ASTUnit {
 
   /// Sorted (by file offset) vector of pairs of file offset/Decl.
   using LocDeclsTy = SmallVector<std::pair<unsigned, Decl *>, 64>;
-  using FileDeclsTy = llvm::DenseMap<FileID, LocDeclsTy *>;
+  using FileDeclsTy = llvm::DenseMap<FileID, std::unique_ptr<LocDeclsTy>>;
 
   /// Map from FileID to the file-level declarations that it contains.
   /// The files and decls are only local (and non-preamble) ones.
diff --git a/clang/lib/Frontend/ASTUnit.cpp b/clang/lib/Frontend/ASTUnit.cpp
index 7920aa2b5cbe1c..57d025b7c32e76 100644
--- a/clang/lib/Frontend/ASTUnit.cpp
+++ b/clang/lib/Frontend/ASTUnit.cpp
@@ -224,7 +224,7 @@ struct ASTUnit::ASTWriterData {
 };
 
 void ASTUnit::clearFileLevelDecls() {
-  llvm::DeleteContainerSeconds(FileDecls);
+  FileDecls.clear();
 }
 
 /// After failing to build a precompiled preamble (due to
@@ -2436,9 +2436,9 @@ void ASTUnit::addFileLevelDecl(Decl *D) {
   if (FID.isInvalid())
     return;
 
-  LocDeclsTy *&Decls = FileDecls[FID];
+  std::unique_ptr<LocDeclsTy> &Decls = FileDecls[FID];
   if (!Decls)
-    Decls = new LocDeclsTy();
+    Decls = std::make_unique<LocDeclsTy>();
 
   std::pair<unsigned, Decl *> LocDecl(Offset, D);