Index: cfe/trunk/lib/Serialization/ASTReader.cpp
===================================================================
--- cfe/trunk/lib/Serialization/ASTReader.cpp
+++ cfe/trunk/lib/Serialization/ASTReader.cpp
@@ -2010,17 +2010,8 @@
   // For an overridden file, there is nothing to validate.
   if (!Overridden && //
       (StoredSize != File->getSize() ||
-#if defined(LLVM_ON_WIN32)
-       false
-#else
-       // In our regression testing, the Windows file system seems to
-       // have inconsistent modification times that sometimes
-       // erroneously trigger this error-handling path.
-       //
-       // FIXME: This probably also breaks HeaderFileInfo lookups on Windows.
        (StoredTime && StoredTime != File->getModificationTime() &&
         !DisableValidation)
-#endif
        )) {
     if (Complain) {
       // Build a list of the PCH imports that got us here (in reverse).