[kernel] Fix identification of enums in ast diff

same issue as with compinfo

src/kernel_services/ast_queries/ast_diff.ml

@@ -362,12 +362,12 @@ let find_candidate_compinfo ?loc:_loc ci =
 
 let find_candidate_enuminfo ?loc:_loc ei =
   if Globals.Types.mem_type Logic_typing.Enum ei.ename then begin
-    match Globals.Types.global Logic_typing.Enum ei.ename with
-    | GEnumTag(ei,_) | GEnumTagDecl(ei,_) -> Some ei
-    | g ->
+    match Globals.Types.find_type Logic_typing.Enum ei.ename with
+    | TEnum(ei,_) -> Some ei
+    | t ->
       Kernel.fatal
-        "Expected enumeration definition instead of %a"
-        Cil_datatype.Global.pretty g
+        "Expected enuminfo instead of %a"
+        Printer.pp_typ t
   end else None
 
 let find_candidate_varinfo ?loc:_loc vi where =

tests/syntax/ast_diff_1.i

@@ -77,4 +77,6 @@ struct s;
 
 extern struct s s;
 
-struct s* use_s() { return &s; }
+enum e;
+
+struct s* use_s() { enum e* x; return &s; }

tests/syntax/ast_diff_2.i

@@ -70,4 +70,6 @@ void local_var_use(int w, int q[][w]) {
 
 extern struct s s;
 
-struct s* use_s() { return &s; }
+enum e;
+
+struct s* use_s() { enum e* x; return &s; }

tests/syntax/oracle/ast_diff_1.res.oracle

@@ -9,6 +9,7 @@
 [AST diff test] Variable y:  => t
 [AST diff test] Variable s:  => s
 [AST diff test] Variable use_s:  => use_s
+[AST diff test] Variable x:  => x
 [AST diff test] Variable has_static_local_x:  => has_static_local_y
 [AST diff test] Variable X:  => X
 [AST diff test] Variable Y: N/A