1 files changed, 1 insertions, 0 deletions
diff --git a/vm_core.h b/vm_core.h
index 8540f8d1de..453c84e394 100644
--- a/vm_core.h
+++ b/vm_core.h
@@ -2011,6 +2011,7 @@ extern void rb_reset_coverages(void);
 void rb_postponed_job_flush(rb_vm_t *vm);
 
 extern VALUE rb_eRactorUnsafeError; // ractor.c
+extern VALUE rb_eRactorIsolationError;
 
 RUBY_SYMBOL_EXPORT_END