Distinguish the various kinds of AST file loading failures:
file corruption, compiler version mismatch, target/language
configuration mismatch, out-of-date AST file. No functionality change
yet.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@166446 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/ASTUnit.cpp b/lib/Frontend/ASTUnit.cpp
index bf78ac5..11bd33e 100644
--- a/lib/Frontend/ASTUnit.cpp
+++ b/lib/Frontend/ASTUnit.cpp
@@ -814,7 +814,10 @@
     break;
 
   case ASTReader::Failure:
-  case ASTReader::IgnorePCH:
+  case ASTReader::OutOfDate:
+  case ASTReader::VersionMismatch:
+  case ASTReader::ConfigurationMismatch:
+  case ASTReader::HadErrors:
     AST->getDiagnostics().Report(diag::err_fe_unable_to_load_pch);
     return NULL;
   }