From 4c4aaa75fc3e04ea63b6aaab8d17760cfdf5b675 Mon Sep 17 00:00:00 2001
From: Pete Vilter <pete.vilter@gmail.com>
Date: Mon, 17 Jan 2022 20:50:35 -0500
Subject: [PATCH] avoid segfault by zeroing out type tag

---
 src/gc.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/gc.c b/src/gc.c
index ff91f89a6ca922..224400c23ba7a8 100644
--- a/src/gc.c
+++ b/src/gc.c
@@ -1201,6 +1201,9 @@ JL_DLLEXPORT jl_value_t *jl_gc_pool_alloc_outer(jl_ptls_t ptls, int pool_offset,
                                           int osize)
 {
     jl_value_t *val = jl_gc_pool_alloc(ptls, pool_offset, osize);
+    // zero out the type tag so it's not garbage
+    jl_set_typeof(val, 0);
+
     maybe_record_alloc_to_profile(val, osize);
     return val;
 }