1 // RUN: %clang_cc1 -std=c++1z -Wno-unused-value -verify %s
2 // RUN: %clang_cc1 -std=c++17 -Wno-unused-value -verify %s
3 
testIf()4 void testIf() {
5   int x = 0;
6   if (x; x) ++x;
7   if (int t = 0; t) ++t; else --t;
8 
9   if (int x, y = 0; y) // expected-note 2 {{previous definition is here}}
10     int x = 0; // expected-error {{redefinition of 'x'}}
11   else
12     int x = 0; // expected-error {{redefinition of 'x'}}
13 
14   if (x; int a = 0) ++a;
15   if (x, +x; int a = 0) // expected-note 2 {{previous definition is here}}
16     int a = 0; // expected-error {{redefinition of 'a'}}
17   else
18     int a = 0; // expected-error {{redefinition of 'a'}}
19 
20   if (int b = 0; b)
21     ;
22   b = 2; // expected-error {{use of undeclared identifier}}
23 }
24 
testSwitch()25 void testSwitch() {
26   int x = 0;
27   switch (x; x) {
28     case 1:
29       ++x;
30   }
31 
32   switch (int x, y = 0; y) {
33     case 1:
34       ++x;
35     default:
36       ++y;
37   }
38 
39   switch (int x, y = 0; y) { // expected-note 2 {{previous definition is here}}
40     case 0:
41       int x = 0; // expected-error {{redefinition of 'x'}}
42     case 1:
43       int y = 0; // expected-error {{redefinition of 'y'}}
44   };
45 
46   switch (x; int a = 0) {
47     case 0:
48       ++a;
49   }
50 
51   switch (x, +x; int a = 0) { // expected-note {{previous definition is here}}
52     case 0:
53       int a = 0; // expected-error {{redefinition of 'a'}} // expected-note {{previous definition is here}}
54     case 1:
55       int a = 0; // expected-error {{redefinition of 'a'}}
56   }
57 
58   switch (int b = 0; b) {
59     case 0:
60       break;
61   }
62   b = 2; // expected-error {{use of undeclared identifier}}
63 }
64 
constexpr_if_init(int n)65 constexpr bool constexpr_if_init(int n) {
66   if (int a = n; ++a > 0)
67     return true;
68   else
69     return false;
70 }
71 
constexpr_switch_init(int n)72 constexpr int constexpr_switch_init(int n) {
73   switch (int p = n + 2; p) {
74     case 0:
75       return 0;
76     case 1:
77       return 1;
78     default:
79       return -1;
80   }
81 }
82 
test_constexpr_init_stmt()83 void test_constexpr_init_stmt() {
84   constexpr bool a = constexpr_if_init(-2);
85   static_assert(!a, "");
86   static_assert(constexpr_if_init(1), "");
87 
88   constexpr int b = constexpr_switch_init(-1);
89   static_assert(b == 1, "");
90   static_assert(constexpr_switch_init(-2) == 0, "");
91   static_assert(constexpr_switch_init(-5) == -1, "");
92 }
93