diff --git a/doc/developer/advance.tex b/doc/developer/advance.tex
index 5e81e4c5acbbe5a1a3b63694c770ce232b130838..770627e22ec1fc35553ea74e5755bdbd1fb2d24d 100644
--- a/doc/developer/advance.tex
+++ b/doc/developer/advance.tex
@@ -3206,9 +3206,9 @@ We present below a thorough description of each field.
 \item[\texttt{compiler}]: defines whether special compiler-specific extensions
   will be enabled. It should be one of the strings below:
   \begin{itemize}
-  \item[\texttt{msvc}]: enables \verb+Cil.msvcMode+, that is,
+  \item[\texttt{msvc}]: enables \verb+Machine.msvcMode+, that is,
     MSVC (Visual Studio)-specific extensions;
-  \item[\texttt{gcc}]: enables \verb+Cil.gccMode+, that is,
+  \item[\texttt{gcc}]: enables \verb+Machine.gccMode+, that is,
     GCC-specific extensions;
   \item[\texttt{generic}] (or any other string): no special
     compiler-specific extensions.
diff --git a/src/kernel_services/ast_data/cil_types.ml b/src/kernel_services/ast_data/cil_types.ml
index aaa0fa132b0164c4b0c67b13a15b1ff810c5e386..185a7fa68fe5f8f67c3219062965e23866e6e546 100644
--- a/src/kernel_services/ast_data/cil_types.ml
+++ b/src/kernel_services/ast_data/cil_types.ml
@@ -754,9 +754,9 @@ and exp_node =
   | Const      of constant              (** Constant *)
   | Lval       of lval                  (** Lvalue *)
   | SizeOf     of typ
-  (** sizeof(<type>). Has [unsigned int] type (ISO 6.5.3.4). This is not
-      turned into a constant because some transformations might want to change
-      types *)
+  (** sizeof(<type>). Has [size_t] type (ISO 6.5.3.4) which depends on machine
+      configuration (cf. {!Machine}). This is not turned into a constant
+      because some transformations might want to change types *)
 
   | SizeOfE    of exp (** sizeof(<expression>) *)
 
@@ -766,7 +766,8 @@ and exp_node =
       type pointer to character. *)
 
   | AlignOf    of typ
-  (** This corresponds to the GCC __alignof_. Has [unsigned int] type *)
+  (** This corresponds to the GCC __alignof_. Has [size_t] type which depends on
+      machine configuration (cf. {!Machine}). *)
 
   | AlignOfE   of exp