1 // RUN: %clang_cc1 -triple x86_64-apple-macosx10.14.0 -verify -Wno-vla %s
2
3 // PR11925
4 int n;
5 int (&f())[n]; // expected-error {{function declaration cannot have variably modified type}}
6
7 namespace PR18581 {
8 template<typename T> struct pod {};
9 template<typename T> struct error {
10 typename T::error e; // expected-error {{cannot be used prior to '::'}}
11 };
12 struct incomplete; // expected-note {{forward declaration}}
13
f(int n)14 void f(int n) {
15 pod<int> a[n];
16 error<int> b[n]; // expected-note {{instantiation}}
17 incomplete c[n]; // expected-error {{incomplete}}
18 }
19 }
20
pr23151(int (&)[* ])21 void pr23151(int (&)[*]) { // expected-error {{variable length array must be bound in function definition}}
22 }
23
test_fold()24 void test_fold() {
25 char a1[(unsigned long)(int *)0+1]{}; // expected-warning{{variable length array folded to constant array as an extension}}
26 char a2[(unsigned long)(int *)0+1] = {}; // expected-warning{{variable length array folded to constant array as an extension}}
27 char a3[(unsigned long)(int *)0+1];
28 }
29
30 // Demonstrate that the check for a static_assert-like use of VLA does not
31 // crash when there's no array size expression at all.
test_null_array_size_expr()32 void test_null_array_size_expr() {
33 int array1[]; // expected-error {{definition of variable with array type needs an explicit size or an initializer}}
34 int array2[] = { 1, 2, 3 };
35 }
36
37 // Show that the check for a static_assert-like use of a VLA properly handles a
38 // dependent array size expression.
39 template <typename Ty>
func(int expr)40 void func(int expr) {
41 int array[sizeof(Ty) ? sizeof(Ty{}) : sizeof(int)];
42 int old_style_assert[expr ? Ty::one : Ty::Neg_one]; // We don't diagnose as a VLA until instantiation
43 }
44