diff --git a/src/why3doc/doc_lexer.mll b/src/why3doc/doc_lexer.mll
index 0a5519f5e3381e6a99b04a6352cbe63c94fb16a3..f6e4d59b92f6973f3c7c4e4b2bf8dba966cb814d 100644
--- a/src/why3doc/doc_lexer.mll
+++ b/src/why3doc/doc_lexer.mll
@@ -74,7 +74,7 @@
               Doc_def.pp_locate id Pp.html_string s
       with Not_found ->
         (* otherwise, just print it *)
-        pp_print_string fmt s
+        Pp.html_string fmt s
     end
 
   type empty_line = PrevEmpty | CurrEmpty | NotEmpty