rename bb_default_error_retval -> xfunc_error_retval
diff --git a/libbb/default_error_retval.c b/libbb/default_error_retval.c
index ff48a67..f4e46a4 100644
--- a/libbb/default_error_retval.c
+++ b/libbb/default_error_retval.c
@@ -16,4 +16,4 @@
 #include <stdlib.h>
 #include "libbb.h"
 
-int bb_default_error_retval = EXIT_FAILURE;
+int xfunc_error_retval = EXIT_FAILURE;