Fix detection of freed emacs_values (Bug#32479)

* src/emacs-module.c (module_free_global_ref): Compare a value to be
freed with all entries of the list.

* test/data/emacs-module/mod-test.c (Fmod_test_globref_free): New
function.
(emacs_module_init): Make it accessible from Lisp.
* test/src/emacs-module-tests.el (mod-test-globref-free-test): New
test which uses it.

1 files changed, 4 insertions, 4 deletions

diff --git a/src/emacs-module.c b/src/emacs-module.c
index 1b19e8033df..c20902d0729 100644
--- a/src/emacs-module.c
+++ b/src/emacs-module.c
@@ -334,20 +334,20 @@ module_free_global_ref (emacs_env *env, emacs_value ref)
       Lisp_Object globals = global_env_private.values;
       Lisp_Object prev = Qnil;
       ptrdiff_t count = 0;
-      for (Lisp_Object tail = global_env_private.values; CONSP (tail);
+      for (Lisp_Object tail = globals; CONSP (tail);
            tail = XCDR (tail))
         {
-          emacs_value global = XSAVE_POINTER (XCAR (globals), 0);
+          emacs_value global = XSAVE_POINTER (XCAR (tail), 0);
           if (global == ref)
             {
               if (NILP (prev))
                 global_env_private.values = XCDR (globals);
               else
-                XSETCDR (prev, XCDR (globals));
+                XSETCDR (prev, XCDR (tail));
               return;
             }
           ++count;
-          prev = globals;
+          prev = tail;
         }
       module_abort ("Global value was not found in list of %"pD"d globals",
                     count);