Add mutex to Scope lookups and insertions

1 files changed, 2 insertions, 0 deletions

diff --git a/src/check_decl.cpp b/src/check_decl.cpp
index a8f1f9aec..06214810b 100644
--- a/src/check_decl.cpp
+++ b/src/check_decl.cpp
@@ -334,6 +334,8 @@ void override_entity_in_scope(Entity *original_entity, Entity *new_entity) {
 	if (found_scope == nullptr) {
 		return;
 	}
+	mutex_lock(&found_scope->mutex);
+	defer (mutex_unlock(&found_scope->mutex));
 
 	// IMPORTANT NOTE(bill, 2021-04-10): Overriding behaviour was flawed in that the
 	// original entity was still used check checked, but the checking was only