diff -u b/Makefile b/Makefile
--- a/scripts/kconfig/menu.c
+++ b/scripts/kconfig/menu.c
@@ -235,16 +235,23 @@ void menu_finalize(struct menu *parent)
 	sym = parent->sym;
 	if (parent->list) {
 		if (sym && sym_is_choice(sym)) {
-			/* find the first choice value and find out choice type */
+			/* find out choice type */
+			enum symbol_type type = S_UNKNOWN;
+
 			for (menu = parent->list; menu; menu = menu->next) {
-				if (menu->sym) {
-					current_entry = parent;
-					menu_set_type(menu->sym->type);
-					current_entry = menu;
-					menu_set_type(sym->type);
-					break;
+				if (menu->sym && menu->sym->type != S_UNKNOWN) {
+					if (type == S_UNKNOWN)
+						type = menu->sym->type;
+					if (type != S_BOOLEAN)
+						break;
+					if (menu->sym->type == S_TRISTATE) {
+						type = S_TRISTATE;
+						break;
+					}
 				}
 			}
+			current_entry = parent;
+			menu_set_type(type);
 			parentdep = expr_alloc_symbol(sym);
 		} else if (parent->prompt)
 			parentdep = parent->prompt->visible.expr;
@@ -253,7 +260,16 @@ void menu_finalize(struct menu *parent)
 
 		for (menu = parent->list; menu; menu = menu->next) {
 			basedep = expr_transform(menu->dep);
-			basedep = expr_alloc_and(expr_copy(parentdep), basedep);
+			dep = parentdep;
+			if (sym && sym_is_choice(sym) && menu->sym) {
+				enum symbol_type type = menu->sym->type;
+
+				if (type == S_UNKNOWN)
+					type = sym->type;
+			     if (type != S_TRISTATE)
+					dep = expr_alloc_comp(E_EQUAL, sym, &symbol_yes);
+			}
+			basedep = expr_alloc_and(expr_copy(dep), basedep);
 			basedep = expr_eliminate_dups(basedep);
 			menu->dep = basedep;
 			if (menu->sym)
@@ -326,7 +342,8 @@ void menu_finalize(struct menu *parent)
 					    "values not supported");
 			}
 			current_entry = menu;
-			menu_set_type(sym->type);
+			if (menu->sym->type == S_UNKNOWN)
+				menu_set_type(sym->type);
 			menu_add_symbol(P_CHOICE, sym, NULL);
 			prop = sym_get_choice_prop(sym);
 			for (ep = &prop->expr; *ep; ep = &(*ep)->left.expr)
--- a/scripts/kconfig/util.c
+++ b/scripts/kconfig/util.c
@@ -84,12 +84,15 @@ void str_free(struct gstr *gs)
 /* Append to growable string */
 void str_append(struct gstr *gs, const char *s)
 {
-	size_t l = strlen(gs->s) + strlen(s) + 1;
-	if (l > gs->len) {
-		gs->s   = realloc(gs->s, l);
-		gs->len = l;
+	size_t l;
+	if (s) {
+		l = strlen(gs->s) + strlen(s) + 1;
+		if (l > gs->len) {
+			gs->s   = realloc(gs->s, l);
+			gs->len = l;
+		}
+		strcat(gs->s, s);
 	}
-	strcat(gs->s, s);
 }
 
 /* Append printf formatted string to growable string */