diff --git a/tools/doc/Cantera.cfg.in b/tools/doc/Cantera.cfg.in
index 62b2cb8ff..795dec961 100755
--- a/tools/doc/Cantera.cfg.in
+++ b/tools/doc/Cantera.cfg.in
@@ -243,7 +243,8 @@ EXPAND_ONLY_PREDEF     = YES
 SEARCH_INCLUDES        = YES
 INCLUDE_PATH           = 
 INCLUDE_FILE_PATTERNS  = 
-PREDEFINED             = 
+PREDEFINED             = WITH_HTML_LOGS \
+                         WITH_PURE_FLUIDS
 EXPAND_AS_DEFINED      = YES
 SKIP_FUNCTION_MACROS   = YES
 #---------------------------------------------------------------------------