diff --git a/source/quickjs-internal.h b/source/quickjs-internal.h
index 497bc0ff..4e5143fa 100644
--- a/source/quickjs-internal.h
+++ b/source/quickjs-internal.h
@@ -95,6 +95,10 @@ void *js_mallocz (JSContext *ctx, size_t size);
 // #define DUMP_OBJECTS    /* dump objects in JS_FreeContext */
 // #define DUMP_READ_OBJECT
 // #define DUMP_ROPE_REBALANCE
+/* dump GC ref stack push/pop with C backtrace on mismatch.
+   When HAVE_ASAN is also set, uses __sanitizer_print_stack_trace()
+   for symbolized output; otherwise falls back to execinfo backtrace(). */
+// #define DUMP_GC_REFS
 
 /* test the GC by forcing it before each object allocation */
 // #define FORCE_GC_AT_MALLOC
diff --git a/source/runtime.c b/source/runtime.c
index e80443af..3dbc3294 100644
--- a/source/runtime.c
+++ b/source/runtime.c
@@ -155,9 +155,46 @@ JSValue *JS_PushGCRef (JSContext *ctx, JSGCRef *ref) {
   return &ref->val;
 }
 
+#ifdef DUMP_GC_REFS
+#ifdef HAVE_ASAN
+void __sanitizer_print_stack_trace(void);
+#else
+#include <execinfo.h>
+#endif
+static void dump_gc_ref_backtrace(const char *label) {
+  fprintf(stderr, "  [%s C backtrace]:\n", label);
+#ifdef HAVE_ASAN
+  __sanitizer_print_stack_trace();
+#else
+  void *bt[16];
+  int n = backtrace(bt, 16);
+  backtrace_symbols_fd(bt, n, 2);
+#endif
+  fprintf(stderr, "\n");
+}
+#endif
+
 JSValue JS_PopGCRef (JSContext *ctx, JSGCRef *ref) {
-  if (ctx->top_gc_ref != ref)
-    fprintf(stderr, "WARN: JS_PopGCRef mismatch (expected %p, got %p)\n", (void*)ctx->top_gc_ref, (void*)ref);
+  if (ctx->top_gc_ref != ref) {
+    fprintf(stderr, "WARN: JS_PopGCRef mismatch (expected %p, got %p)\n",
+            (void *)ctx->top_gc_ref, (void *)ref);
+#ifdef DUMP_GC_REFS
+    /* Walk the stack to show what's between top and the ref being popped */
+    int depth = 0;
+    JSGCRef *walk = ctx->top_gc_ref;
+    while (walk && walk != ref && depth < 16) {
+      fprintf(stderr, "  orphan #%d: ref=%p val=0x%llx\n",
+              depth, (void *)walk, (unsigned long long)walk->val);
+      walk = walk->prev;
+      depth++;
+    }
+    if (walk == ref)
+      fprintf(stderr, "  (%d orphaned ref(s) between top and pop target)\n", depth);
+    else
+      fprintf(stderr, "  (pop target not found in stack — chain is corrupt)\n");
+    dump_gc_ref_backtrace("pop site");
+#endif
+  }
   ctx->top_gc_ref = ref->prev;
   return ref->val;
 }
@@ -6009,6 +6046,7 @@ exception_ret:
   return -1;
 
 exception:
+  JS_PopGCRef (ctx, &v_ref);
   JS_PopGCRef (ctx, &prop_ref);
   JS_PopGCRef (ctx, &tab_ref);
   JS_PopGCRef (ctx, &sep1_ref);
diff --git a/syntax_suite.ce b/syntax_suite.ce
index 51a36662..17dd396b 100644
--- a/syntax_suite.ce
+++ b/syntax_suite.ce
@@ -387,7 +387,8 @@ run("function early return", function() {
 
 run("extra and missing args", function() {
   var fn = function(a, b) { return a + b }
-  assert_eq(fn(1, 2, 3), 3, "extra args ignored")
+  assert_eq(should_disrupt(function() { fn(1, 2, 3) }), true, "extra args disrupt")
+  assert_eq(fn(1, 2), 3, "exact args work")
   var fn2 = function(a, b) { return a }
   assert_eq(fn2(1), 1, "missing args ok")
 })