bug#68954: [PATCH] Crasher in treesit_traverse_get_predicate

[Dominique Quatravaux <dominique@quatravaux.org>]

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Because nothing guarantees or enforces that either Vtreesit_thing_settings,
or the cdrs of its elements, are cons cells, it is easy to construct values
for `treesit-thing-settings' that make Emacs crash (e.g., when calling
`prog-fill-reindent-defun' from any tree-sitter enabled mode).

The attached patch fixes that.

--
 Dominique Quatravaux
 dominique@quatravaux.org

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--- treesit.c.orig	2024-02-06 18:01:23
+++ treesit.c	2024-02-06 18:01:41
@@ -3268,11 +3268,11 @@
 static Lisp_Object
 treesit_traverse_get_predicate (Lisp_Object thing, Lisp_Object language)
 {
-  Lisp_Object cons = assq_no_quit (language, Vtreesit_thing_settings);
+  Lisp_Object cons = assq_no_signal (language, Vtreesit_thing_settings);
   if (NILP (cons))
     return Qnil;
   Lisp_Object definitions = XCDR (cons);
-  Lisp_Object entry = assq_no_quit (thing, definitions);
+  Lisp_Object entry = assq_no_signal (thing, definitions);
   if (NILP (entry))
     return Qnil;
   /* ENTRY looks like (THING PRED).  */