Refactor the classification of attributes

Introduce Cutil.class_of_attribute to return the class of the given attribute: one among
Attr_type  attribute related to types  (e.g. "aligned")
Attr_struct attribute related to struct/union/enum types (e.g. "packed")
Attr_function attribute related to function types (e.g. "noreturn")
Attr_name  attribute related to variable and function declarations (e.g. "section")
Attr_unknown  attribute was not declared

Cutil.declare_attribute is used to associate a class to a custom attribute.
Standard attributes (const, volatile, _Alignas, etc) are Attr_type.

cfronted/C2C.ml: declare the few attributes that CompCert honors currently.
cparser/GCC.ml: a bigger list of attributes taken from GCC, for reference only.

1 files changed, 13 insertions, 0 deletions

diff --git a/cfrontend/C2C.ml b/cfrontend/C2C.ml
index b7fe5fb0..183af347 100644
--- a/cfrontend/C2C.ml
+++ b/cfrontend/C2C.ml
@@ -267,6 +267,19 @@ let builtins =
   { typedefs = builtins_generic.typedefs @ CBuiltins.builtins.typedefs;
     functions = builtins_generic.functions @ CBuiltins.builtins.functions }
 
+(** ** The known attributes *)
+
+let attributes = [
+  (* type-related *)
+  ("aligned", Cutil.Attr_type);
+  (* struct-related *)
+  ("packed", Cutil.Attr_struct);
+  (* function-related (currently none) *)
+  (* name-related *)
+  ("section", Cutil.Attr_name)
+]
+  
+
 (** ** Functions used to handle string literals *)
 
 let stringNum = ref 0   (* number of next global for string literals *)