work around Doxygen bug triggered by r814874, which caused many classes to disappear
from the docs.
diff --git a/Eigen/Core b/Eigen/Core
index 0e5f82c..3666e07 100644
--- a/Eigen/Core
+++ b/Eigen/Core
@@ -28,7 +28,10 @@
 #include "src/Core/Functors.h"
 #include "src/Core/MatrixBase.h"
 #include "src/Core/Coeffs.h"
+#ifndef EIGEN_PARSED_BY_DOXYGEN // work around Doxygen bug triggered by Assign.h r814874
+                                // at least confirmed with Doxygen 1.5.5 and 1.5.6
 #include "src/Core/Assign.h"
+#endif
 #include "src/Core/MatrixStorage.h"
 #include "src/Core/NestByValue.h"
 #include "src/Core/Flagged.h"
diff --git a/doc/Doxyfile.in b/doc/Doxyfile.in
index d700e7e..26f4394 100644
--- a/doc/Doxyfile.in
+++ b/doc/Doxyfile.in
@@ -1174,7 +1174,8 @@
 # undefined via #undef or recursively expanded use the := operator 
 # instead of the = operator.
 
-PREDEFINED             = EIGEN_EMPTY_STRUCT
+PREDEFINED             = EIGEN_EMPTY_STRUCT \
+                         EIGEN_PARSED_BY_DOXYGEN
 
 # If the MACRO_EXPANSION and EXPAND_ONLY_PREDEF tags are set to YES then 
 # this tag can be used to specify a list of macro names that should be expanded. 
diff --git a/doc/Mainpage.dox b/doc/Mainpage.dox
index f54882f..ce86937 100644
--- a/doc/Mainpage.dox
+++ b/doc/Mainpage.dox
@@ -12,4 +12,4 @@
 
 */
 
-}
\ No newline at end of file
+}