Fix crash overriding predefined function in package body only

Issue #760

NEWS.md

@@ -11,6 +11,8 @@
 - Fixed a memory leak in the `--print-deps` command.
 - Fixed a crash when evaluating globally static expressions during
   elaboration with coverage enabled (#759).
+- Fixed an analysis crash where a predefined function for a type
+  declared in a package is overridden in the package body only (#760).
 
 ## Version 1.10.2 - 2023-08-20
 - Fixed a crash due to an array bounds check being incorrectly optimised

src/names.c

@@ -797,7 +797,8 @@ static symbol_t *make_visible(scope_t *s, ident_t name, tree_t decl,
                && (tree_flags(dd->tree) & TREE_F_PREDEFINED)) {
          // Allow pre-defined operators be to hidden by
          // user-defined subprograms in the same region
-         tree_set_flag(dd->tree, TREE_F_HIDDEN);
+         if (!tree_frozen(dd->tree))
+            tree_set_flag(dd->tree, TREE_F_HIDDEN);  // Will be deleted later
          dd->visibility = HIDDEN;
       }
       else if (is_forward_decl(decl, dd->tree)) {

test/parse/issue760.vhd

@@ -0,0 +1,11 @@
+package issue760 is
+    type t_array is array (natural range <>) of integer;
+end package;
+
+package body issue760 is
+    -- Hides predef defined in package header
+    impure function to_string (x : t_array) return string is
+    begin
+        return "";
+    end function;
+end package body;

test/test_parse.c

@@ -5665,6 +5665,28 @@ START_TEST(test_issue751)
 }
 END_TEST
 
+START_TEST(test_issue760)
+{
+   set_standard(STD_19);
+
+   input_from_file(TESTDIR "/parse/issue760.vhd");
+
+   tree_t p = parse();
+   fail_if(p == NULL);
+   fail_unless(tree_kind(p) == T_PACKAGE);
+
+   lib_put(lib_work(), p);
+
+   tree_t b = parse();
+   fail_if(b == NULL);
+   fail_unless(tree_kind(b) == T_PACK_BODY);
+
+   fail_unless(parse() == NULL);
+
+   fail_if_errors();
+}
+END_TEST
+
 Suite *get_parse_tests(void)
 {
    Suite *s = suite_create("parse");
@@ -5784,6 +5806,7 @@ Suite *get_parse_tests(void)
    tcase_add_test(tc_core, test_issue727);
    tcase_add_test(tc_core, test_visibility8);
    tcase_add_test(tc_core, test_issue751);
+   tcase_add_test(tc_core, test_issue760);
    suite_add_tcase(s, tc_core);
 
    return s;