diff --git a/m-array.h b/m-array.h
index 7bbd788a..d1249aac 100644
--- a/m-array.h
+++ b/m-array.h
@@ -59,7 +59,7 @@
 
 /* Prepare a clean compilation failure */
 #define ARRAYI_OPLIST_FAILURE(name, oplist)		\
-  M_LIB_ERROR(ARGUMENT_OF_ARRAY_OPLIST_IS_NOT_AN_OPLIST, name, oplist)
+  ((M_LIB_ERROR(ARGUMENT_OF_ARRAY_OPLIST_IS_NOT_AN_OPLIST, name, oplist)))
 
 /* OPLIST definition of a dynamic array */
 /* FIXME: Do we want to export some methods as they are slow and 
diff --git a/m-bptree.h b/m-bptree.h
index e9bca068..80e45054 100644
--- a/m-bptree.h
+++ b/m-bptree.h
@@ -106,7 +106,7 @@
 
 /* Prepare a clean compilation failure */
 #define BPTREEI_KEY_OPLIST_FAILURE(name, oplist)		\
-  M_LIB_ERROR(ARGUMENT_OF_BPTREE_OPLIST_IS_NOT_AN_OPLIST, name, oplist)
+  ((M_LIB_ERROR(ARGUMENT_OF_BPTREE_OPLIST_IS_NOT_AN_OPLIST, name, oplist)))
 
 /* OPLIST definition of a b+tree */
 #define BPTREEI_KEY_OPLIST_P3(name, oplist)                             \
@@ -156,7 +156,7 @@
 
 /* Prepare a clean compilation failure */
 #define BPTREEI_OPLIST2_FAILURE(name, key_oplist, value_oplist)	\
-  M_LIB_ERROR(ARGUMENT_OF_BPTREE_OPLIST_IS_NOT_AN_OPLIST, name, key_oplist, value_oplist)
+  ((M_LIB_ERROR(ARGUMENT_OF_BPTREE_OPLIST_IS_NOT_AN_OPLIST, name, key_oplist, value_oplist)))
 
 #define BPTREEI_OPLIST2_P4(name, key_oplist, value_oplist)		\
   (INIT(M_C(name, _init)),						\
diff --git a/m-buffer.h b/m-buffer.h
index 1dc2ce61..19866ccb 100644
--- a/m-buffer.h
+++ b/m-buffer.h
@@ -1074,7 +1074,7 @@ M_C(name, _init)(buffer_t v, size_t size)                               \
 
 /* Prepare a clean compilation failure */
 #define BUFFERI_OPLIST_FAILURE(name, oplist)		\
-  M_LIB_ERROR(ARGUMENT_OF_BUFFER_OPLIST_IS_NOT_AN_OPLIST, name, oplist)
+  ((M_LIB_ERROR(ARGUMENT_OF_BUFFER_OPLIST_IS_NOT_AN_OPLIST, name, oplist)))
 
 /* OPLIST defininition of a buffer */
 #define BUFFERI_OPLIST_P3(name, oplist)					\
diff --git a/m-concurrent.h b/m-concurrent.h
index b8e6a4c5..b1fad81e 100644
--- a/m-concurrent.h
+++ b/m-concurrent.h
@@ -68,7 +68,7 @@
 
 /* Prepare a clean compilation failure */
 #define CONCURRENTI_OPLIST_FAILURE(name, oplist)		\
-  M_LIB_ERROR(ARGUMENT_OF_CONCURRENT_OPLIST_IS_NOT_AN_OPLIST, name, oplist)
+  ((M_LIB_ERROR(ARGUMENT_OF_CONCURRENT_OPLIST_IS_NOT_AN_OPLIST, name, oplist)))
 
 /* OPLIST definition
    GET_KEY is not present as its interface is not compatible with a concurrent
diff --git a/m-deque.h b/m-deque.h
index 7f5dcae1..b8a3c99a 100644
--- a/m-deque.h
+++ b/m-deque.h
@@ -960,7 +960,7 @@
 
 /* Prepare a clean compilation failure */
 #define DEQUEI_OPLIST_FAILURE(name, oplist)		\
-  M_LIB_ERROR(ARGUMENT_OF_DEQUE_OPLIST_IS_NOT_AN_OPLIST, name, oplist)
+  ((M_LIB_ERROR(ARGUMENT_OF_DEQUE_OPLIST_IS_NOT_AN_OPLIST, name, oplist)))
 
 /* OPLIST definition of a deque */
 #define DEQUEI_OPLIST_P3(name, oplist)					\
diff --git a/m-dict.h b/m-dict.h
index 976f8bef..ee5e88f1 100644
--- a/m-dict.h
+++ b/m-dict.h
@@ -969,7 +969,7 @@
 
 /* Prepare a clean compilation failure */
 #define DICTI_OPLIST_FAILURE(name, key_oplist, value_oplist)	\
-  M_LIB_ERROR(ARGUMENT_OF_DICT_OPLIST_IS_NOT_AN_OPLIST, name, key_oplist, value_oplist)
+  ((M_LIB_ERROR(ARGUMENT_OF_DICT_OPLIST_IS_NOT_AN_OPLIST, name, key_oplist, value_oplist)))
 
 /* Define the oplist of a dictionnary
    NOTE: IT_REF is not exported so that the contained appears as not modifiable
@@ -1026,7 +1026,7 @@
 
 /* Prepare a clean compilation failure */
 #define DICTI_SET_OPLIST_FAILURE(name, oplist)				\
-  M_LIB_ERROR(ARGUMENT_OF_DICT_SET_OPLIST_IS_NOT_AN_OPLIST, name, oplist)
+  ((M_LIB_ERROR(ARGUMENT_OF_DICT_SET_OPLIST_IS_NOT_AN_OPLIST, name, oplist)))
 
 /* Define the oplist of a set */
 #define DICTI_SET_OPLIST_P3(name, oplist)                               \
diff --git a/m-funcobj.h b/m-funcobj.h
index 68588f07..da8aee56 100644
--- a/m-funcobj.h
+++ b/m-funcobj.h
@@ -97,7 +97,7 @@
 
 /* Prepare a clean compilation failure */
 #define FUNCOBJI_INS_ATTR_OPLIST_FAILURE(name, ...)			\
-  M_LIB_ERROR(ONE_ARGUMENT_OF_FUNC_OBJ_INS_OPLIST_IS_NOT_AN_OPLIST, name, __VA_ARGS__)
+  ((M_LIB_ERROR(ONE_ARGUMENT_OF_FUNC_OBJ_INS_OPLIST_IS_NOT_AN_OPLIST, name, __VA_ARGS__)))
 
 /* Define at least the oplist */
 #define FUNCOBJI_INS_ATTR_OPLIST_P3(name, ...)				\
diff --git a/m-i-list.h b/m-i-list.h
index 9e86f842..35a72994 100644
--- a/m-i-list.h
+++ b/m-i-list.h
@@ -76,7 +76,7 @@ typedef struct ilist_head_s {
 
 /* Prepare a clean compilation failure */
 #define ILISTI_OPLIST_FAILURE(name, oplist)		\
-  M_LIB_ERROR(ARGUMENT_OF_ILIST_OPLIST_IS_NOT_AN_OPLIST, name, oplist)
+  ((M_LIB_ERROR(ARGUMENT_OF_ILIST_OPLIST_IS_NOT_AN_OPLIST, name, oplist)))
 
 /* Define the oplist of an ilist of type */
 #define ILISTI_OPLIST_P3(name, oplist)					\
diff --git a/m-i-shared.h b/m-i-shared.h
index 8c2bb1e2..9123bff2 100644
--- a/m-i-shared.h
+++ b/m-i-shared.h
@@ -62,7 +62,7 @@
 
 /* Prepare a clean compilation failure */
 #define ISHAREDI_PTR_OPLIST_FAILURE(name, oplist)			\
-  M_LIB_ERROR(ARGUMENT_OF_ISHARED_PTR_OPLIST_IS_NOT_AN_OPLIST, name, oplist)
+  ((M_LIB_ERROR(ARGUMENT_OF_ISHARED_PTR_OPLIST_IS_NOT_AN_OPLIST, name, oplist)))
 
 // Define the oplist
 #define ISHAREDI_PTR_OPLIST_P3(name, oplist) (                          \
diff --git a/m-list.h b/m-list.h
index 4d611e87..be5d54d7 100644
--- a/m-list.h
+++ b/m-list.h
@@ -63,7 +63,7 @@
 
 /* Prepare a clean compilation failure */
 #define LISTI_OPLIST_FAILURE(name, oplist)		\
-  M_LIB_ERROR(ARGUMENT_OF_LIST_OPLIST_IS_NOT_AN_OPLIST, name, oplist)
+  ((M_LIB_ERROR(ARGUMENT_OF_LIST_OPLIST_IS_NOT_AN_OPLIST, name, oplist)))
 
 /* OPLIST definition of a list and list_dual_push */
 #define LISTI_OPLIST_P3(name, oplist)                                   \
diff --git a/m-prioqueue.h b/m-prioqueue.h
index cb5726ee..5ec9bcd4 100644
--- a/m-prioqueue.h
+++ b/m-prioqueue.h
@@ -59,7 +59,7 @@
 
 /* Prepare a clean compilation failure */
 #define PRIOQUEUEI_OPLIST_FAILURE(name, oplist)		\
-  M_LIB_ERROR(ARGUMENT_OF_PRIOQUEUE_OPLIST_IS_NOT_AN_OPLIST, name, oplist)
+  ((M_LIB_ERROR(ARGUMENT_OF_PRIOQUEUE_OPLIST_IS_NOT_AN_OPLIST, name, oplist)))
 
 /* Define oplist of a priority queue */
 #define PRIOQUEUEI_OPLIST_P3(name, oplist)                              \
diff --git a/m-rbtree.h b/m-rbtree.h
index fa427fa9..887c5ec0 100644
--- a/m-rbtree.h
+++ b/m-rbtree.h
@@ -57,7 +57,7 @@
 
 /* Prepare a clean compilation failure */
 #define RBTREEI_OPLIST_FAILURE(name, oplist)		\
-  M_LIB_ERROR(ARGUMENT_OF_RBTREE_OPLIST_IS_NOT_AN_OPLIST, name, oplist)
+  ((M_LIB_ERROR(ARGUMENT_OF_RBTREE_OPLIST_IS_NOT_AN_OPLIST, name, oplist)))
 
 /* OPLIST definition of a rbtree
    NOTE: IT_REF is not exported so that the contained appears as not modifiable
diff --git a/m-shared.h b/m-shared.h
index 3f40115a..68e66d60 100644
--- a/m-shared.h
+++ b/m-shared.h
@@ -74,7 +74,7 @@
 
 /* Prepare a clean compilation failure */
 #define SHAREDI_PTR_OPLIST_FAILURE(name, oplist)			\
-  M_LIB_ERROR(ARGUMENT_OF_SHARED_PTR_OPLIST_IS_NOT_AN_OPLIST, name, oplist)
+  ((M_LIB_ERROR(ARGUMENT_OF_SHARED_PTR_OPLIST_IS_NOT_AN_OPLIST, name, oplist)))
 
 #define SHAREDI_PTR_OPLIST_P3(name, oplist) (                           \
   INIT(M_C(name, _init)),                                               \
diff --git a/m-snapshot.h b/m-snapshot.h
index b5574c14..56b51562 100644
--- a/m-snapshot.h
+++ b/m-snapshot.h
@@ -72,7 +72,7 @@
 
 /* Prepare a clean compilation failure */
 #define SNAPSHOTI_OPLIST_FAILURE(name, oplist)		\
-  M_LIB_ERROR(ARGUMENT_OF_SNAPSHOT_OPLIST_IS_NOT_AN_OPLIST, name, oplist)
+  ((M_LIB_ERROR(ARGUMENT_OF_SNAPSHOT_OPLIST_IS_NOT_AN_OPLIST, name, oplist)))
 
 /* Define the oplist of a snapshot */
 #define SNAPSHOTI_OPLIST_P3(name, oplist)                               \
diff --git a/m-variant.h b/m-variant.h
index 1f3da3f4..76ba0138 100644
--- a/m-variant.h
+++ b/m-variant.h
@@ -659,8 +659,8 @@
   M_IF(M_REDUCE(M_OPLIST_P, M_AND, __VA_ARGS__))(VARIANTI_OPLIST_P3, VARIANTI_OPLIST_FAILURE)(name, __VA_ARGS__)
 
 /* Prepare a clean compilation failure */
-#define VARIANTI_OPLIST_FAILURE(name, ...)				\
-  M_LIB_ERROR(ONE_ARGUMENT_OF_VARIANT_OPLIST_IS_NOT_AN_OPLIST, name, __VA_ARGS__)
+#define VARIANTI_OPLIST_FAILURE(name, ...)                              \
+  ((M_LIB_ERROR(ONE_ARGUMENT_OF_VARIANT_OPLIST_IS_NOT_AN_OPLIST, name, __VA_ARGS__)))
 
 #define VARIANTI_OPLIST_P3(name, ...)                                   \
   (INIT(M_C(name,_init)),                                               \