Fixed a crash on replaying Preamble's PP conditional stack.

Summary:
The crash occurs when the first token after a preamble is a macro
expansion.
Fixed by moving replayPreambleConditionalStack from Parser into
Preprocessor. It is now called right after the predefines file is
processed.

Reviewers: erikjv, bkramer, klimek, yvvan

Reviewed By: bkramer

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D36872

llvm-svn: 311330

1 files changed, 12 insertions, 1 deletions

diff --git a/clang/lib/Lex/PPLexerChange.cpp b/clang/lib/Lex/PPLexerChange.cpp
index 5a589d6a17b..36d7028da68 100644
--- a/clang/lib/Lex/PPLexerChange.cpp
+++ b/clang/lib/Lex/PPLexerChange.cpp
@@ -458,10 +458,16 @@ bool Preprocessor::HandleEndOfFile(Token &Result, bool isEndOfMacro) {
       SourceMgr.setNumCreatedFIDsForFileID(CurPPLexer->getFileID(), NumFIDs);
     }
 
+    bool ExitedFromPredefinesFile = false;
     FileID ExitedFID;
-    if (Callbacks && !isEndOfMacro && CurPPLexer)
+    if (!isEndOfMacro && CurPPLexer) {
       ExitedFID = CurPPLexer->getFileID();
 
+      assert(PredefinesFileID.isValid() &&
+             "HandleEndOfFile is called before PredefinesFileId is set");
+      ExitedFromPredefinesFile = (PredefinesFileID == ExitedFID);
+    }
+
     if (LeavingSubmodule) {
       // We're done with this submodule.
       Module *M = LeaveSubmodule(/*ForPragma*/false);
@@ -489,6 +495,11 @@ bool Preprocessor::HandleEndOfFile(Token &Result, bool isEndOfMacro) {
                              PPCallbacks::ExitFile, FileType, ExitedFID);
     }
 
+    // Restore conditional stack from the preamble right after exiting from the
+    // predefines file.
+    if (ExitedFromPredefinesFile)
+      replayPreambleConditionalStack();
+
     // Client should lex another token unless we generated an EOM.
     return LeavingSubmodule;
   }