diff --git a/compat/terminal.c b/compat/terminal.c
index 0afda730f2..d54efa1c5d 100644
--- a/compat/terminal.c
+++ b/compat/terminal.c
@@ -594,7 +594,7 @@ void restore_term(void)
 {
 }
 
-char *git_terminal_prompt(const char *prompt, int echo)
+char *git_terminal_prompt(const char *prompt, int echo UNUSED)
 {
 	return getpass(prompt);
 }