diff --git a/cmd-new-session.c b/cmd-new-session.c
index 8e5520c6..7df7dcb6 100644
--- a/cmd-new-session.c
+++ b/cmd-new-session.c
@@ -74,8 +74,8 @@ cmd_new_session_exec(struct cmd *self, struct cmdq_item *item)
 	struct environ		*env;
 	struct termios		 tio, *tiop;
 	const char		*newname, *target, *update, *errstr, *template;
-	const char		*path, *cwd, *to_free = NULL;
-	char		       **argv, *cmd, *cause, *cp;
+	const char		*path, *cmd, *cwd, *to_free = NULL;
+	char		       **argv, *cause, *cp;
 	int			 detached, already_attached, idx, argc;
 	u_int			 sx, sy;
 	struct format_tree	*ft;
@@ -217,7 +217,7 @@ cmd_new_session_exec(struct cmd *self, struct cmdq_item *item)
 		cmd = options_get_string(global_s_options, "default-command");
 		if (cmd != NULL && *cmd != '\0') {
 			argc = 1;
-			argv = &cmd;
+			argv = (char **)&cmd;
 		} else {
 			argc = 0;
 			argv = NULL;
diff --git a/names.c b/names.c
index 6a368825..877b2504 100644
--- a/names.c
+++ b/names.c
@@ -121,7 +121,8 @@ static char *
 format_window_name(struct window *w)
 {
 	struct format_tree	*ft;
-	char			*fmt, *name;
+	const char		*fmt;
+	char			*name;
 
 	ft = format_create(NULL, 0);
 	format_defaults_window(ft, w);
diff --git a/options.c b/options.c
index 09e8669a..811606b2 100644
--- a/options.c
+++ b/options.c
@@ -162,7 +162,7 @@ options_set_string(struct options *oo, const char *name, int append,
 	return (o);
 }
 
-char *
+const char *
 options_get_string(struct options *oo, const char *name)
 {
 	struct options_entry	*o;
@@ -221,7 +221,7 @@ options_set_style(struct options *oo, const char *name, int append,
 	return (o);
 }
 
-struct grid_cell *
+const struct grid_cell *
 options_get_style(struct options *oo, const char *name)
 {
 	struct options_entry	*o;
diff --git a/server-client.c b/server-client.c
index 50ae94fd..dbe3e7ec 100644
--- a/server-client.c
+++ b/server-client.c
@@ -294,12 +294,13 @@ server_client_detach(struct client *c, enum msgtype msgtype)
 	proc_send_s(c->peer, msgtype, s->name);
 }
 
-/* Execute command to replace a client, */
+/* Execute command to replace a client. */
 void
 server_client_exec(struct client *c, const char *cmd)
 {
 	struct session	*s = c->session;
-	char		*msg, *shell;
+	char		*msg;
+	const char	*shell;
 	size_t		 cmdsize, shellsize;
 
 	if (*cmd == '\0')
diff --git a/server-fn.c b/server-fn.c
index 83b3fe86..6e629ccf 100644
--- a/server-fn.c
+++ b/server-fn.c
@@ -33,9 +33,9 @@ static void		 server_destroy_session_group(struct session *);
 void
 server_fill_environ(struct session *s, struct environ *env)
 {
-	char	*term;
-	u_int	 idx;
-	long	 pid;
+	const char	*term;
+	u_int		 idx;
+	long		 pid;
 
 	if (s != NULL) {
 		term = options_get_string(global_options, "default-terminal");
diff --git a/status.c b/status.c
index c54d8f40..9fc9a502 100644
--- a/status.c
+++ b/status.c
@@ -278,18 +278,19 @@ status_get_window_at(struct client *c, u_int x)
 int
 status_redraw(struct client *c)
 {
-	struct screen_write_ctx	ctx;
-	struct session	       *s = c->session;
-	struct winlink	       *wl;
-	struct screen		old_status, window_list;
-	struct grid_cell	stdgc, lgc, rgc, gc;
-	struct options	       *oo;
-	time_t			t;
-	char		       *left, *right, *sep;
-	u_int			offset, needed;
-	u_int			wlstart, wlwidth, wlavailable, wloffset, wlsize;
-	size_t			llen, rlen, seplen;
-	int			larrow, rarrow;
+	struct screen_write_ctx	 ctx;
+	struct session		*s = c->session;
+	struct winlink		*wl;
+	struct screen		 old_status, window_list;
+	struct grid_cell	 stdgc, lgc, rgc, gc;
+	struct options		*oo;
+	time_t			 t;
+	char			*left, *right;
+	const char		*sep;
+	u_int			 offset, needed;
+	u_int			 wlstart, wlwidth, wlavailable, wloffset, wlsize;
+	size_t			 llen, rlen, seplen;
+	int			 larrow, rarrow;
 
 	/* No status line? */
 	if (c->tty.sy == 0 || !options_get_number(s->options, "status"))
diff --git a/style.c b/style.c
index f4a8f05f..26bb75a9 100644
--- a/style.c
+++ b/style.c
@@ -182,7 +182,7 @@ style_update_old(struct options *oo, const char *name, struct grid_cell *gc)
 void
 style_apply(struct grid_cell *gc, struct options *oo, const char *name)
 {
-	struct grid_cell	*gcp;
+	const struct grid_cell	*gcp;
 
 	memcpy(gc, &grid_default_cell, sizeof *gc);
 	gcp = options_get_style(oo, name);
@@ -195,7 +195,7 @@ style_apply(struct grid_cell *gc, struct options *oo, const char *name)
 void
 style_apply_update(struct grid_cell *gc, struct options *oo, const char *name)
 {
-	struct grid_cell	*gcp;
+	const struct grid_cell	*gcp;
 
 	gcp = options_get_style(oo, name);
 	if (gcp->fg != 8)
diff --git a/tmux.h b/tmux.h
index e04ab771..6a925ebc 100644
--- a/tmux.h
+++ b/tmux.h
@@ -1632,13 +1632,13 @@ struct options_entry *options_find(struct options *, const char *);
 void	options_remove(struct options *, const char *);
 struct options_entry * printflike(4, 5) options_set_string(struct options *,
 	    const char *, int, const char *, ...);
-char   *options_get_string(struct options *, const char *);
+const char *options_get_string(struct options *, const char *);
 struct options_entry *options_set_number(struct options *, const char *,
 	    long long);
 long long options_get_number(struct options *, const char *);
 struct options_entry *options_set_style(struct options *, const char *, int,
 	    const char *);
-struct grid_cell *options_get_style(struct options *, const char *);
+const struct grid_cell *options_get_style(struct options *, const char *);
 
 /* options-table.c */
 extern const struct options_table_entry options_table[];
diff --git a/tty-term.c b/tty-term.c
index cdebeed7..9e29188d 100644
--- a/tty-term.c
+++ b/tty-term.c
@@ -388,8 +388,7 @@ tty_term_find(char *name, int fd, char **cause)
 	struct tty_code				*code;
 	u_int					 i;
 	int		 			 n, error;
-	char					*s;
-	const char				*acs;
+	const char				*s, *acs;
 
 	LIST_FOREACH(term, &tty_terms, entry) {
 		if (strcmp(term->name, name) == 0) {