1 files changed, 9 insertions, 1 deletions
diff --git a/lib/Frontend/CompilerInstance.cpp b/lib/Frontend/CompilerInstance.cpp
index 9e7b630bf1..22a74fcc35 100644
--- a/lib/Frontend/CompilerInstance.cpp
+++ b/lib/Frontend/CompilerInstance.cpp
@@ -600,10 +600,18 @@ bool CompilerInstance::InitializeSourceManager(const FrontendInputFile &Input,
                                                FileManager &FileMgr,
                                                SourceManager &SourceMgr,
                                                const FrontendOptions &Opts) {
-  StringRef InputFile = Input.getFile();
   SrcMgr::CharacteristicKind
     Kind = Input.isSystem() ? SrcMgr::C_System : SrcMgr::C_User;
 
+  if (Input.isBuffer()) {
+    SourceMgr.createMainFileIDForMemBuffer(Input.getBuffer(), Kind);
+    assert(!SourceMgr.getMainFileID().isInvalid() &&
+           "Couldn't establish MainFileID!");
+    return true;
+  }
+
+  StringRef InputFile = Input.getFile();
+
   // Figure out where to get and map in the main file.
   if (InputFile != "-") {
     const FileEntry *File = FileMgr.getFile(InputFile);