r223900 - Made the ASTImporter resilient if it can't import

[Sean Callanan]

Author: spyffe
Date: Tue Dec  9 19:26:39 2014
New Revision: 223900

URL: http://llvm.org/viewvc/llvm-project?rev=223900&view=rev
Log:
Made the ASTImporter resilient if it can't import
SourceLocations.  LLDB rarely has the same files
mapped into the target AST context as the source
AST context, so the ASTImporter shouldn't expect
to see those files there.

This started to become a problem when importing
entities from modules -- these have proper source
locations, in contrast to all the ASTs LLDB
creates which have empty ones.

Modified:
    cfe/trunk/lib/AST/ASTImporter.cpp

Modified: cfe/trunk/lib/AST/ASTImporter.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/AST/ASTImporter.cpp?rev=223900&r1=223899&r2=223900&view=diff
==============================================================================
--- cfe/trunk/lib/AST/ASTImporter.cpp (original)
+++ cfe/trunk/lib/AST/ASTImporter.cpp Tue Dec  9 19:26:39 2014
@@ -4923,7 +4923,10 @@ SourceLocation ASTImporter::Import(Sourc
   FromLoc = FromSM.getSpellingLoc(FromLoc);
   std::pair<FileID, unsigned> Decomposed = FromSM.getDecomposedLoc(FromLoc);
   SourceManager &ToSM = ToContext.getSourceManager();
-  return ToSM.getLocForStartOfFile(Import(Decomposed.first))
+  FileID ToFileID = Import(Decomposed.first);
+  if (ToFileID.isInvalid())
+    return SourceLocation();
+  return ToSM.getLocForStartOfFile(ToFileID)
              .getLocWithOffset(Decomposed.second);
 }
 
@@ -4954,6 +4957,8 @@ FileID ASTImporter::Import(FileID FromID
     // FIXME: We definitely want to re-use the existing MemoryBuffer, rather
     // than mmap the files several times.
     const FileEntry *Entry = ToFileManager.getFile(Cache->OrigEntry->getName());
+    if (!Entry)
+      return FileID();
     ToID = ToSM.createFileID(Entry, ToIncludeLoc, 
                              FromSLoc.getFile().getFileCharacteristic());
   } else {