[DebugInfo] Don't emit checksums when compiling a preprocessed CPP

Fixes PR41215

Differential Revision: https://reviews.llvm.org/D60283

llvm-svn: 361296

1 files changed, 7 insertions, 2 deletions

diff --git a/clang/lib/Basic/SourceManager.cpp b/clang/lib/Basic/SourceManager.cpp
index 712cbb0d0ea..e62cef7ec55 100644
--- a/clang/lib/Basic/SourceManager.cpp
+++ b/clang/lib/Basic/SourceManager.cpp
@@ -1430,6 +1430,7 @@ PresumedLoc SourceManager::getPresumedLoc(SourceLocation Loc,
   // To get the source name, first consult the FileEntry (if one exists)
   // before the MemBuffer as this will avoid unnecessarily paging in the
   // MemBuffer.
+  FileID FID = LocInfo.first;
   StringRef Filename;
   if (C->OrigEntry)
     Filename = C->OrigEntry->getName();
@@ -1453,8 +1454,12 @@ PresumedLoc SourceManager::getPresumedLoc(SourceLocation Loc,
     if (const LineEntry *Entry =
           LineTable->FindNearestLineEntry(LocInfo.first, LocInfo.second)) {
       // If the LineEntry indicates a filename, use it.
-      if (Entry->FilenameID != -1)
+      if (Entry->FilenameID != -1) {
         Filename = LineTable->getFilename(Entry->FilenameID);
+        // The contents of files referenced by #line are not in the
+        // SourceManager
+        FID = FileID::get(0);
+      }
 
       // Use the line number specified by the LineEntry.  This line number may
       // be multiple lines down from the line entry.  Add the difference in
@@ -1473,7 +1478,7 @@ PresumedLoc SourceManager::getPresumedLoc(SourceLocation Loc,
     }
   }
 
-  return PresumedLoc(Filename.data(), LineNo, ColNo, IncludeLoc);
+  return PresumedLoc(Filename.data(), FID, LineNo, ColNo, IncludeLoc);
 }
 
 /// Returns whether the PresumedLoc for a given SourceLocation is