diff --git a/ident.c b/ident.c
index caf41fb2a9..967895d885 100644
--- a/ident.c
+++ b/ident.c
@@ -59,7 +59,7 @@ static struct passwd *xgetpwuid_self(int *is_bogus)
 
 static void copy_gecos(const struct passwd *w, struct strbuf *name)
 {
-	char *src;
+	const char *src;
 
 	/* Traditionally GECOS field had office phone numbers etc, separated
 	 * with commas.  Also & stands for capitalized form of the login name.