Fix ownership of the MemoryBuffer in a FrontendInputFile.

This fixes a possible crash on certain kinds of corrupted AST file, but
checking in an AST file corrupted in just the right way will be a maintenance
nightmare because the format changes frequently.

llvm-svn: 312851

1 files changed, 5 insertions, 4 deletions

diff --git a/clang/lib/Frontend/FrontendAction.cpp b/clang/lib/Frontend/FrontendAction.cpp
index 704d5150985..52e2799deb5 100644
--- a/clang/lib/Frontend/FrontendAction.cpp
+++ b/clang/lib/Frontend/FrontendAction.cpp
@@ -754,10 +754,11 @@ bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
         goto failure;
 
       // Reinitialize the main file entry to refer to the new input.
-      if (!CI.InitializeSourceManager(FrontendInputFile(
-              Buffer.release(), Input.getKind().withFormat(InputKind::Source),
-              CurrentModule->IsSystem)))
-        goto failure;
+      auto Kind = CurrentModule->IsSystem ? SrcMgr::C_System : SrcMgr::C_User;
+      auto &SourceMgr = CI.getSourceManager();
+      auto BufferID = SourceMgr.createFileID(std::move(Buffer), Kind);
+      assert(BufferID.isValid() && "couldn't creaate module buffer ID");
+      SourceMgr.setMainFileID(BufferID);
     }
   }