diff --git a/types.c b/types.c
index b1269bb..c1862e0 100644
--- a/types.c
+++ b/types.c
@@ -396,17 +396,6 @@ PUREFUNC bool is_numeric_type(type_t *t)
     return t->tag == IntType || t->tag == BigIntType || t->tag == NumType;
 }
 
-PUREFUNC bool supports_optionals(type_t *t)
-{
-    switch (t->tag) {
-    case BoolType: case ByteType: case CStringType: case BigIntType: case NumType: case TextType:
-    case ArrayType: case SetType: case TableType: case FunctionType: case ClosureType:
-    case PointerType: case IntType:
-        return true;
-    default: return false;
-    }
-}
-
 PUREFUNC size_t type_size(type_t *t)
 {
 #pragma GCC diagnostic ignored "-Wswitch-default"
diff --git a/types.h b/types.h
index 46469c6..d92e217 100644
--- a/types.h
+++ b/types.h
@@ -148,7 +148,6 @@ PUREFUNC bool can_promote(type_t *actual, type_t *needed);
 PUREFUNC const char *enum_single_value_tag(type_t *enum_type, type_t *t);
 PUREFUNC bool is_int_type(type_t *t);
 PUREFUNC bool is_numeric_type(type_t *t);
-PUREFUNC bool supports_optionals(type_t *t);
 PUREFUNC size_t type_size(type_t *t);
 PUREFUNC size_t type_align(type_t *t);
 PUREFUNC size_t padded_type_size(type_t *t);