From 726924917d84060e932b379dba6519e78cd8e79e Mon Sep 17 00:00:00 2001
From: Andre Noll <maan@tuebingen.mpg.de>
Date: Thu, 20 Mar 2025 00:18:30 +0100
Subject: [PATCH] Teach the mood parser to not leak on errors.

Attempting to load an incomplete mood definition such as "1 &&"
currently causes memory leaks because the memory for the partial
syntax tree is never freed.

Employ bison's %destructor directive to call mp_free_ast() whenever
a syntax error happens.
---
 yy/mp.y | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/yy/mp.y b/yy/mp.y
index dc04488f..f2f0756d 100644
--- a/yy/mp.y
+++ b/yy/mp.y
@@ -350,6 +350,9 @@ bool mp_eval_ast(struct mp_ast_node *root, struct mp_context *ctx)
 %type <node> exp
 %type <node> boolexp
 
+/* Called when a symbol is automatically discarded due to a syntax error. */
+%destructor {mp_free_ast($$);} string exp boolexp
+
 %%
 
 program:
-- 
2.39.5