1 files changed, 3 insertions, 3 deletions

diff --git a/apps/plugins/puzzles/src/nullgame.c b/apps/plugins/puzzles/src/nullgame.c
index 183b1e39c2..bc19c1e6f0 100644
--- a/apps/plugins/puzzles/src/nullgame.c
+++ b/apps/plugins/puzzles/src/nullgame.c
@@ -78,7 +78,7 @@ static game_params *custom_params(const config_item *cfg)
     return NULL;
 }
 
-static char *validate_params(const game_params *params, int full)
+static const char *validate_params(const game_params *params, int full)
 {
     return NULL;
 }
@@ -89,7 +89,7 @@ static char *new_game_desc(const game_params *params, random_state *rs,
     return dupstr("FIXME");
 }
 
-static char *validate_desc(const game_params *params, const char *desc)
+static const char *validate_desc(const game_params *params, const char *desc)
 {
     return NULL;
 }
@@ -119,7 +119,7 @@ static void free_game(game_state *state)
 }
 
 static char *solve_game(const game_state *state, const game_state *currstate,
-                        const char *aux, char **error)
+                        const char *aux, const char **error)
 {
     return NULL;
 }