diff --git a/doc/Doxyfile b/doc/Doxyfile
index 6bdb864..5e4fc41 100644
--- a/doc/Doxyfile
+++ b/doc/Doxyfile
@@ -2072,7 +2072,7 @@ PERLMOD_MAKEVAR_PREFIX =
 # C-preprocessor directives found in the sources and include files.
 # The default value is: YES.
 
-ENABLE_PREPROCESSING   = YES
+ENABLE_PREPROCESSING   = NO
 
 # If the MACRO_EXPANSION tag is set to YES, doxygen will expand all macro names
 # in the source code. If set to NO, only conditional compilation will be