When loading an AST file, set SourceManager::MainFileID to the main file of the AST file,
as suggested by Tom Honermann.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@147612 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Lex/Preprocessor.cpp b/lib/Lex/Preprocessor.cpp
index cfa9e23..5dda964 100644
--- a/lib/Lex/Preprocessor.cpp
+++ b/lib/Lex/Preprocessor.cpp
@@ -400,19 +400,23 @@
assert(NumEnteredSourceFiles == 0 && "Cannot reenter the main file!");
FileID MainFileID = SourceMgr.getMainFileID();
- // Enter the main file source buffer.
- EnterSourceFile(MainFileID, 0, SourceLocation());
-
- // If we've been asked to skip bytes in the main file (e.g., as part of a
- // precompiled preamble), do so now.
- if (SkipMainFilePreamble.first > 0)
- CurLexer->SkipBytes(SkipMainFilePreamble.first,
- SkipMainFilePreamble.second);
+ // If MainFileID is loaded it means we loaded an AST file, no need to enter
+ // a main file.
+ if (!SourceMgr.isLoadedFileID(MainFileID)) {
+ // Enter the main file source buffer.
+ EnterSourceFile(MainFileID, 0, SourceLocation());
- // Tell the header info that the main file was entered. If the file is later
- // #imported, it won't be re-entered.
- if (const FileEntry *FE = SourceMgr.getFileEntryForID(MainFileID))
- HeaderInfo.IncrementIncludeCount(FE);
+ // If we've been asked to skip bytes in the main file (e.g., as part of a
+ // precompiled preamble), do so now.
+ if (SkipMainFilePreamble.first > 0)
+ CurLexer->SkipBytes(SkipMainFilePreamble.first,
+ SkipMainFilePreamble.second);
+
+ // Tell the header info that the main file was entered. If the file is later
+ // #imported, it won't be re-entered.
+ if (const FileEntry *FE = SourceMgr.getFileEntryForID(MainFileID))
+ HeaderInfo.IncrementIncludeCount(FE);
+ }
// Preprocess Predefines to populate the initial preprocessor state.
llvm::MemoryBuffer *SB =