diff --git a/src/options.c b/src/options.c
index 93b6415..183160d 100644
--- a/src/options.c
+++ b/src/options.c
@@ -722,6 +722,7 @@ void get_cfg(options_t *opt, int argc, char *const *argv, bool shadow_enable,
 			break;
 		case 305:
 			// --shadow-exclude-reg
+			free(opt->shadow_exclude_reg_str);
 			opt->shadow_exclude_reg_str = strdup(optarg);
 			log_warn("--shadow-exclude-reg is deprecated. You are likely "
 			         "better off using --shadow-exclude anyway");