Fix crash on :toggle file-args

Reported-by: Johannes Altmanninger <[email protected]>

Author: koutcher

NEWS.adoc

@@ -35,6 +35,7 @@ Bug fixes:
  - Fix navigation between chunks after splitting chunk. (#1101, #1162)
  - Fix status line when toggling general options. (#1163, #1164)
  - Honor reference-format = hide:tag in diff view. (#1168, #1170)
+ - Fix crash on :toggle file-args.
 
 tig-2.5.4
 ---------

src/prompt.c

@@ -798,8 +798,10 @@ prompt_toggle_option(struct view *view, const char *argv[], const char *prefix,
 		int i;
 
 		if (argv_size(argv) <= 2) {
-			argv_free(*opt);
-			(*opt)[0] = NULL;
+			if (*opt) {
+				argv_free(*opt);
+				(*opt)[0] = NULL;
+			}
 			return SUCCESS;
 		}