3 files changed, 27 insertions, 7 deletions
diff --git a/clang/include/clang/Tooling/JSONCompilationDatabase.h b/clang/include/clang/Tooling/JSONCompilationDatabase.h
index 0e6c893969d..2a13fc155ce 100644
--- a/clang/include/clang/Tooling/JSONCompilationDatabase.h
+++ b/clang/include/clang/Tooling/JSONCompilationDatabase.h
@@ -116,6 +116,10 @@ private:
   // Maps file paths to the compile command lines for that file.
   llvm::StringMap<std::vector<CompileCommandRef>> IndexByFile;
 
+  /// All the compile commands in the order that they were provided in the
+  /// JSON stream.
+  std::vector<CompileCommandRef> AllCommands;
+
   FileMatchTrie MatchTrie;
 
   std::unique_ptr<llvm::MemoryBuffer> Database;
diff --git a/clang/lib/Tooling/JSONCompilationDatabase.cpp b/clang/lib/Tooling/JSONCompilationDatabase.cpp
index dd4d7a8f083..299fbdc149b 100644
--- a/clang/lib/Tooling/JSONCompilationDatabase.cpp
+++ b/clang/lib/Tooling/JSONCompilationDatabase.cpp
@@ -206,11 +206,7 @@ JSONCompilationDatabase::getAllFiles() const {
 std::vector<CompileCommand>
 JSONCompilationDatabase::getAllCompileCommands() const {
   std::vector<CompileCommand> Commands;
-  for (llvm::StringMap< std::vector<CompileCommandRef> >::const_iterator
-        CommandsRefI = IndexByFile.begin(), CommandsRefEnd = IndexByFile.end();
-      CommandsRefI != CommandsRefEnd; ++CommandsRefI) {
-    getCommands(CommandsRefI->getValue(), Commands);
-  }
+  getCommands(AllCommands, Commands);
   return Commands;
 }
 
@@ -337,8 +333,9 @@ bool JSONCompilationDatabase::parse(std::string &ErrorMessage) {
     } else {
       llvm::sys::path::native(FileName, NativeFilePath);
     }
-    IndexByFile[NativeFilePath].push_back(
-        CompileCommandRef(Directory, File, *Command));
+    auto Cmd = CompileCommandRef(Directory, File, *Command);
+    IndexByFile[NativeFilePath].push_back(Cmd);
+    AllCommands.push_back(Cmd);
     MatchTrie.insert(NativeFilePath);
   }
   return true;
diff --git a/clang/unittests/Tooling/CompilationDatabaseTest.cpp b/clang/unittests/Tooling/CompilationDatabaseTest.cpp
index b7e7a72d235..380d86fc566 100644
--- a/clang/unittests/Tooling/CompilationDatabaseTest.cpp
+++ b/clang/unittests/Tooling/CompilationDatabaseTest.cpp
@@ -118,6 +118,25 @@ TEST(JSONCompilationDatabase, GetAllCompileCommands) {
   EXPECT_EQ(FileName2, Commands[1].Filename) << ErrorMessage;
   ASSERT_EQ(1u, Commands[1].CommandLine.size());
   EXPECT_EQ(Command2, Commands[1].CommandLine[0]) << ErrorMessage;
+
+  // Check that order is preserved.
+  Commands = getAllCompileCommands(
+      ("[{\"directory\":\"" + Directory2 + "\"," +
+             "\"command\":\"" + Command2 + "\","
+             "\"file\":\"" + FileName2 + "\"},"
+       " {\"directory\":\"" + Directory1 + "\"," +
+             "\"command\":\"" + Command1 + "\","
+             "\"file\":\"" + FileName1 + "\"}]").str(),
+      ErrorMessage);
+  EXPECT_EQ(2U, Commands.size()) << ErrorMessage;
+  EXPECT_EQ(Directory2, Commands[0].Directory) << ErrorMessage;
+  EXPECT_EQ(FileName2, Commands[0].Filename) << ErrorMessage;
+  ASSERT_EQ(1u, Commands[0].CommandLine.size());
+  EXPECT_EQ(Command2, Commands[0].CommandLine[0]) << ErrorMessage;
+  EXPECT_EQ(Directory1, Commands[1].Directory) << ErrorMessage;
+  EXPECT_EQ(FileName1, Commands[1].Filename) << ErrorMessage;
+  ASSERT_EQ(1u, Commands[1].CommandLine.size());
+  EXPECT_EQ(Command1, Commands[1].CommandLine[0]) << ErrorMessage;
 }
 
 static CompileCommand findCompileArgsInJsonDatabase(StringRef FileName,