diff --git a/docs/Doxyfile.in b/docs/Doxyfile.in
index 170850f..4bb2be8 100644
--- a/docs/Doxyfile.in
+++ b/docs/Doxyfile.in
@@ -1365,7 +1365,7 @@ INCLUDE_FILE_PATTERNS  =
 # undefined via #undef or recursively expanded use the := operator
 # instead of the = operator.
 
-PREDEFINED             =
+PREDEFINED             = "TINS_IS_CXX11=1"
 
 # 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.