bug#31996: 27.0.50; [w32] while dumping: assertion failed: specpdl_ptr->kind == SPECPDL_UNWIND_PTR && specpdl_ptr->unwind_ptr.func == xfree

[Noam Postavsky <npostavs@gmail.com>]

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X-Debbugs-CC: Paul Eggert <eggert@cs.ucla.edu>


gdb --args ./temacs --batch  --load loadup bootstrap

(gdb) p specpdl_ptr->kind
$1 = SPECPDL_UNWIND_ARRAY
(gdb) p specpdl_ptr->unwind_ptr.func
$2 = (void (*)(void *)) 0x53898
(gdb) p specpdl_ptr->unwind_array.func
$3 = (void (*)(Lisp_Object)) 0x53898

I guess it's related to the #31750 changes. The problem doesn't seem
especially platform-specific, but I've haven't seen this on my
GNU/Linux box.
The attached patch fixes it, though I'm not sure if it's
entirely correct.

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--- i/src/lisp.h
+++ w/src/lisp.h
@@ -4543,7 +4543,8 @@ safe_free (ptrdiff_t sa_count)
   while (specpdl_ptr != specpdl + sa_count)
     {
       specpdl_ptr--;
-      eassert ((specpdl_ptr->kind == SPECPDL_UNWIND_PTR || specpdl_ptr->kind == SPECPDL_UNWIND_ARRAY)
+      eassert ((specpdl_ptr->kind == SPECPDL_UNWIND_PTR
+                || specpdl_ptr->kind == SPECPDL_UNWIND_ARRAY)
 	       && specpdl_ptr->unwind_ptr.func == xfree);
       xfree (specpdl_ptr->unwind_ptr.arg);
     }
diff --git i/src/w32fns.c w/src/w32fns.c
index 3bd3209..59edb31 100644
--- i/src/w32fns.c
+++ w/src/w32fns.c
@@ -4551,7 +4551,7 @@ w32_wnd_proc (HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
 	 dialog boxes, such as the file selection dialog or font
 	 selection dialog.  So something else is needed to fix the
 	 former without breaking the latter.  See bug#11732.  */
-      break;
+      goto dflt;
 
     case WM_IME_ENDCOMPOSITION:
       ignore_ime_char = 0;