1// Copyright 2018 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5// +build !nacl
6
7package runtime_test
8
9import (
10	"reflect"
11	"runtime"
12	"testing"
13	"unsafe"
14)
15
16// Assert that the size of important structures do not change unexpectedly.
17
18func TestSizeof(t *testing.T) {
19	if runtime.Compiler != "gc" {
20		t.Skip("skipping size test; specific to gc compiler")
21	}
22
23	const _64bit = unsafe.Sizeof(uintptr(0)) == 8
24
25	var tests = []struct {
26		val    interface{} // type as a value
27		_32bit uintptr     // size on 32bit platforms
28		_64bit uintptr     // size on 64bit platforms
29	}{
30		{runtime.G{}, 216, 376}, // g, but exported for testing
31	}
32
33	for _, tt := range tests {
34		want := tt._32bit
35		if _64bit {
36			want = tt._64bit
37		}
38		got := reflect.TypeOf(tt.val).Size()
39		if want != got {
40			t.Errorf("unsafe.Sizeof(%T) = %d, want %d", tt.val, got, want)
41		}
42	}
43}
44