diff --git a/CRT.h b/CRT.h
index 00141b55..6f38bd3c 100644
--- a/CRT.h
+++ b/CRT.h
@@ -98,6 +98,8 @@ typedef enum ColorElements_ {
    LAST_COLORELEMENT
 } ColorElements;
 
+void CRT_fatalError(const char* note) __attribute__ ((noreturn));
+
 
 // TODO: centralize these in Settings.