diff --git a/src/kernel_services/ast_transformations/contract_special_float.mli b/src/kernel_services/ast_transformations/contract_special_float.mli
index 676dc9b6fa4483a8132c3939540f520efd3df9dc..3dd81628ff8b6e38ce4a1ed45466c725bc8149c7 100644
--- a/src/kernel_services/ast_transformations/contract_special_float.mli
+++ b/src/kernel_services/ast_transformations/contract_special_float.mli
@@ -20,3 +20,4 @@
 (*                                                                        *)
 (**************************************************************************)
 
+(* No function exported *)
diff --git a/src/plugins/reduc/Reduc.mli b/src/plugins/reduc/Reduc.mli
index 676dc9b6fa4483a8132c3939540f520efd3df9dc..49010ca1bf725583e882f7160ef2de77907aade5 100644
--- a/src/plugins/reduc/Reduc.mli
+++ b/src/plugins/reduc/Reduc.mli
@@ -20,3 +20,4 @@
 (*                                                                        *)
 (**************************************************************************)
 
+(* This plugin does not export anything *)
diff --git a/src/plugins/studia/studia_gui.mli b/src/plugins/studia/studia_gui.mli
index cce51dc83ef23f10bb7ed95d5a93dfc632b91896..5f8a7338f77671ab186f3c88a3688c883d28b0df 100644
--- a/src/plugins/studia/studia_gui.mli
+++ b/src/plugins/studia/studia_gui.mli
@@ -19,3 +19,5 @@
 (*  for more details (enclosed in the file licenses/LGPLv2.1).            *)
 (*                                                                        *)
 (**************************************************************************)
+
+(* no function exported *)